diff --git a/DSView/pv/deviceagent.cpp b/DSView/pv/deviceagent.cpp
index 1d0defe5..b01f65ba 100644
--- a/DSView/pv/deviceagent.cpp
+++ b/DSView/pv/deviceagent.cpp
@@ -29,6 +29,7 @@ DeviceAgent::DeviceAgent()
     _dev_handle = NULL;
     _di = NULL;
     _dev_type = 0;
+    _callback = NULL;
 }
 
 void DeviceAgent::update()
@@ -258,52 +259,60 @@ bool DeviceAgent::get_status(struct sr_status &status, gboolean prg)
     }
     return false;
 }
+
+void DeviceAgent::config_changed()
+{
+    if (_callback != NULL){
+        _callback->DeviceConfigChanged();
+    }
+}
  
 //---------------device config-----------/
 
-  int DeviceAgent::get_work_mode()
-   {
-       return ds_get_actived_device_mode();
-   }
+int DeviceAgent::get_work_mode()
+{
+    return ds_get_actived_device_mode();
+}
 
-   const struct sr_config_info* DeviceAgent::get_config_info(int key)
-    {
-        return ds_get_actived_device_config_info(key);
-    }
+const struct sr_config_info *DeviceAgent::get_config_info(int key)
+{
+    return ds_get_actived_device_config_info(key);
+}
 
-    const struct sr_config_info* DeviceAgent::get_config_info_by_name(const char *optname)
-    {
-        return ds_get_actived_device_config_info_by_name(optname);
-    }
+const struct sr_config_info *DeviceAgent::get_config_info_by_name(const char *optname)
+{
+    return ds_get_actived_device_config_info_by_name(optname);
+}
 
-    bool DeviceAgent::get_device_status(struct sr_status &status, gboolean prg)
+bool DeviceAgent::get_device_status(struct sr_status &status, gboolean prg)
+{
+    if (ds_get_actived_device_status(&status, prg) == SR_OK)
     {
-        if (ds_get_actived_device_status(&status, prg) == SR_OK){
-            return true;
-        }
-        return false;
+        return true;
     }
+    return false;
+}
 
-    struct sr_config* DeviceAgent::new_config(int key, GVariant *data)
-    {
-        return ds_new_config(key, data);
-    }
+struct sr_config *DeviceAgent::new_config(int key, GVariant *data)
+{
+    return ds_new_config(key, data);
+}
 
-    void DeviceAgent::free_config(struct sr_config *src)
-    {
-        ds_free_config(src);
-    }
+void DeviceAgent::free_config(struct sr_config *src)
+{
+    ds_free_config(src);
+}
 
-    bool DeviceAgent::is_running()
-    {
-        return ds_is_collecting() > 0;
-    }
+bool DeviceAgent::is_collecting()
+{
+    return ds_is_collecting() > 0;
+}
 
-    GSList* DeviceAgent::get_channels()
-    {
-        assert(_dev_handle);
-        return ds_get_actived_device_channels();
-    }
+GSList *DeviceAgent::get_channels()
+{
+    assert(_dev_handle);
+    return ds_get_actived_device_channels();
+}
 
 //---------------device config end -----------/
 
diff --git a/DSView/pv/deviceagent.h b/DSView/pv/deviceagent.h
index cd96b224..818685f2 100644
--- a/DSView/pv/deviceagent.h
+++ b/DSView/pv/deviceagent.h
@@ -27,6 +27,12 @@
 #include <libsigrok.h>
 #include <QString>
 
+class IDeviceAgentCallback
+{
+    public:
+        virtual void DeviceConfigChanged()=0;
+};
+
 class DeviceAgent
 {
 public:
@@ -62,7 +68,11 @@ public:
 
     inline bool is_hardware(){
         return _dev_type == DEV_TYPE_USB;
-    }  
+    }
+
+    inline void set_callback(IDeviceAgentCallback *callback){
+        _callback = callback;
+    }
 
     GVariant* get_config(const sr_channel *ch, const sr_channel_group *group, int key);
 
@@ -123,13 +133,11 @@ public:
 
     bool have_enabled_channel();
 
-    bool get_status(struct sr_status &status, gboolean prg);
-
-    bool is_running();
+    bool get_status(struct sr_status &status, gboolean prg); 
 
     GSList* get_channels();
 
-      /**
+    /**
      * Start collect data.
      */
     bool start();
@@ -139,7 +147,10 @@ public:
      */
     bool stop();
 
-protected: 
+    bool is_collecting();
+
+protected:
+    void config_changed();
 
     //---------------device config-----------/
 public:
@@ -162,6 +173,7 @@ private:
     QString     _dev_name;
     QString     _driver_name;
     struct sr_dev_inst  *_di;
+    IDeviceAgentCallback *_callback;
 };
 
 
diff --git a/DSView/pv/dialogs/deviceoptions.cpp b/DSView/pv/dialogs/deviceoptions.cpp
index 6d4131cc..b7a65db3 100644
--- a/DSView/pv/dialogs/deviceoptions.cpp
+++ b/DSView/pv/dialogs/deviceoptions.cpp
@@ -147,8 +147,7 @@ DeviceOptions::DeviceOptions(QWidget *parent) :
     try_resize_scroll();
   
     connect(&_mode_check, SIGNAL(timeout()), this, SLOT(mode_check()));
-    connect(button_box, SIGNAL(accepted()), this, SLOT(accept())); 
-    connect(_device_agent, SIGNAL(device_updated()), this, SLOT(reject()));
+    connect(button_box, SIGNAL(accepted()), this, SLOT(accept()));
 
     _mode_check.setInterval(100);
     _mode_check.start();  
diff --git a/DSView/pv/dialogs/dsdialog.h b/DSView/pv/dialogs/dsdialog.h
index 1f586fe3..b8ab9903 100644
--- a/DSView/pv/dialogs/dsdialog.h
+++ b/DSView/pv/dialogs/dsdialog.h
@@ -29,7 +29,7 @@
 #include <QDialogButtonBox>
 
 #include "../toolbars/titlebar.h"
-#include "../interface/uicallback.h"
+#include "../interface/icallbacks.h"
 
 class QDialogButtonBox;
  
diff --git a/DSView/pv/dialogs/dsomeasure.cpp b/DSView/pv/dialogs/dsomeasure.cpp
index d9fb4a88..8d62bb76 100644
--- a/DSView/pv/dialogs/dsomeasure.cpp
+++ b/DSView/pv/dialogs/dsomeasure.cpp
@@ -77,7 +77,7 @@ DsoMeasure::DsoMeasure(SigSession *session, View &parent,
 
     connect(_button_box.button(QDialogButtonBox::Cancel), SIGNAL(clicked()), this, SLOT(reject()));
     connect(_button_box.button(QDialogButtonBox::Reset), SIGNAL(clicked()), this, SLOT(reset()));
-    connect(_session->get_device(), SIGNAL(device_updated()), this, SLOT(reject()));
+    connect(_session->device_event_object(), SIGNAL(device_updated()), this, SLOT(reject()));
 }
 
 DsoMeasure::~DsoMeasure(){
diff --git a/DSView/pv/dialogs/fftoptions.cpp b/DSView/pv/dialogs/fftoptions.cpp
index 35a2f9d9..d1db5c47 100644
--- a/DSView/pv/dialogs/fftoptions.cpp
+++ b/DSView/pv/dialogs/fftoptions.cpp
@@ -220,7 +220,7 @@ FftOptions::FftOptions(QWidget *parent, SigSession *session) :
     connect(&_button_box, SIGNAL(rejected()), this, SLOT(reject()));
     connect(_window_combobox, SIGNAL(currentIndexChanged(int)), this, SLOT(window_changed(int)));
     connect(_len_combobox, SIGNAL(currentIndexChanged(int)), this, SLOT(len_changed(int)));
-    connect(_session->get_device(), SIGNAL(device_updated()), this, SLOT(reject()));    
+    connect(_session->device_event_object(), SIGNAL(device_updated()), this, SLOT(reject()));
 }
 
 FftOptions::~FftOptions(){
@@ -243,12 +243,13 @@ void FftOptions::accept()
                 spectrumTraces->get_spectrum_stack()->set_sample_interval(_interval_combobox->currentData().toInt());
                 spectrumTraces->get_spectrum_stack()->set_windows_index(_window_combobox->currentData().toInt());
                 spectrumTraces->set_view_mode(_view_combobox->currentData().toUInt());
-                //spectrumTraces->init_zoom();
+                
                 spectrumTraces->set_dbv_range(_dbv_combobox->currentData().toInt());
                 spectrumTraces->set_enable(_en_checkbox->isChecked());
-                if (_session->get_capture_state() == SigSession::Stopped &&
-                    spectrumTraces->enabled())
+
+                if (_session->is_stopped_status() && spectrumTraces->enabled()){
                     spectrumTraces->get_spectrum_stack()->calc_fft();
+                }
             }
         }
     }
diff --git a/DSView/pv/dialogs/interval.cpp b/DSView/pv/dialogs/interval.cpp
index ee53ec3e..cb45e5da 100644
--- a/DSView/pv/dialogs/interval.cpp
+++ b/DSView/pv/dialogs/interval.cpp
@@ -26,9 +26,8 @@
 namespace pv {
 namespace dialogs {
 
-Interval::Interval(SigSession *session, QWidget *parent) :
+Interval::Interval(QWidget *parent) :
     DSDialog(parent),
-    _session(session),
     _button_box(QDialogButtonBox::Ok,
         Qt::Horizontal, this)
 {
@@ -36,6 +35,7 @@ Interval::Interval(SigSession *session, QWidget *parent) :
     _interval_spinBox = NULL;
     _interval_slider = NULL;
     _bSetting = false;
+    _bDone = false;
 
     setMinimumWidth(300);
     _interval_label = new QLabel(tr("Interval(s): "), this);
@@ -46,9 +46,6 @@ Interval::Interval(SigSession *session, QWidget *parent) :
     _interval_slider = new QSlider(Qt::Horizontal, this);
     _interval_slider->setRange(0, 10);
 
-    _interval_slider->setValue((int)_session->get_repeat_intvl());
-    _interval_spinBox->setValue(_session->get_repeat_intvl());
-
     QGridLayout *glayout = new QGridLayout(this);
     glayout->addWidget(_interval_label, 0, 0);
     glayout->addWidget(_interval_spinBox, 0, 1);
@@ -66,7 +63,7 @@ Interval::Interval(SigSession *session, QWidget *parent) :
 void Interval::accept()
 {
     using namespace Qt;
-    _session->set_repeat_intvl(_interval_spinBox->value());
+    _bDone = true;
     QDialog::accept();
 }
 
@@ -77,14 +74,24 @@ void Interval::reject()
     QDialog::reject();
 }
 
+void Interval::set_interval(double value)
+{
+    _interval_slider->setValue((int)value);
+    _interval_spinBox->setValue(value);
+}
+
+double Interval::get_interval()
+{
+    return _interval_spinBox->value();
+}
+
 void Interval::on_slider_changed(int value)
 {
     if (!_bSetting){
         _bSetting = true;
         _interval_spinBox->setValue((double)value);
         _bSetting = false;
-    }
-    
+    }    
 }
 
 void Interval::on_inputbox_changed(double value)
@@ -93,8 +100,7 @@ void Interval::on_inputbox_changed(double value)
         _bSetting = true;
         _interval_slider->setValue((int)value);
         _bSetting = false;
-    }
-    
+    }    
 }
 
 } // namespace dialogs
diff --git a/DSView/pv/dialogs/interval.h b/DSView/pv/dialogs/interval.h
index 421b9d2a..825c0330 100644
--- a/DSView/pv/dialogs/interval.h
+++ b/DSView/pv/dialogs/interval.h
@@ -40,25 +40,31 @@ class Interval : public DSDialog
 	Q_OBJECT
 
 public:
-    Interval(SigSession *session, QWidget *parent);
+    Interval(QWidget *parent);
+
+    void set_interval(double value);
+    double get_interval();
+
+    inline bool is_done(){
+        return _bDone;
+    }
 
 protected:
 	void accept();
-    void reject();
-
+    void reject(); 
+    
 private Q_SLOTS:
         void on_slider_changed(int value);
         void on_inputbox_changed(double value);
 
 private:
-    SigSession *_session;
-
     QLabel *_interval_label;
     QDoubleSpinBox *_interval_spinBox;
     QSlider *_interval_slider;
 
     QDialogButtonBox _button_box;
     bool    _bSetting;
+    bool    _bDone;
 };
 
 } // namespace dialogs
diff --git a/DSView/pv/dialogs/protocolexp.cpp b/DSView/pv/dialogs/protocolexp.cpp
index 7835ec84..30c712b4 100644
--- a/DSView/pv/dialogs/protocolexp.cpp
+++ b/DSView/pv/dialogs/protocolexp.cpp
@@ -97,7 +97,7 @@ ProtocolExp::ProtocolExp(QWidget *parent, SigSession *session) :
 
     connect(&_button_box, SIGNAL(accepted()), this, SLOT(accept()));
     connect(&_button_box, SIGNAL(rejected()), this, SLOT(reject()));
-    connect(_session->get_device(), SIGNAL(device_updated()), this, SLOT(reject()));
+    connect(_session->device_event_object(), SIGNAL(device_updated()), this, SLOT(reject()));
 
 }
 
diff --git a/DSView/pv/dialogs/protocollist.cpp b/DSView/pv/dialogs/protocollist.cpp
index 4144cc58..63803b51 100644
--- a/DSView/pv/dialogs/protocollist.cpp
+++ b/DSView/pv/dialogs/protocollist.cpp
@@ -90,7 +90,7 @@ ProtocolList::ProtocolList(QWidget *parent, SigSession *session) :
     connect(&_button_box, SIGNAL(accepted()), this, SLOT(accept()));
     connect(_protocol_combobox, SIGNAL(currentIndexChanged(int)), this, SLOT(set_protocol(int)));
     set_protocol(_protocol_combobox->currentIndex());
-    connect(_session->get_device(), SIGNAL(device_updated()), this, SLOT(reject()));
+    connect(_session->device_event_object(), SIGNAL(device_updated()), this, SLOT(reject()));
 
 }
 
diff --git a/DSView/pv/dialogs/regionoptions.cpp b/DSView/pv/dialogs/regionoptions.cpp
index 8c455d26..303d67b8 100644
--- a/DSView/pv/dialogs/regionoptions.cpp
+++ b/DSView/pv/dialogs/regionoptions.cpp
@@ -73,7 +73,7 @@ RegionOptions::RegionOptions(view::View *view, SigSession *session, QWidget *par
     setTitle(tr("Region"));
 
     connect(&_button_box, SIGNAL(accepted()), this, SLOT(set_region()));
-    connect(_session->get_device(), SIGNAL(device_updated()), this, SLOT(reject()));
+    connect(_session->device_event_object(), SIGNAL(device_updated()), this, SLOT(reject()));
 
 }
 
diff --git a/DSView/pv/dialogs/search.cpp b/DSView/pv/dialogs/search.cpp
index ff630146..6a2ee47a 100644
--- a/DSView/pv/dialogs/search.cpp
+++ b/DSView/pv/dialogs/search.cpp
@@ -85,7 +85,6 @@ Search::Search(QWidget *parent, SigSession *session, std::map<uint16_t, QString>
 
     connect(&search_buttonBox, SIGNAL(accepted()), this, SLOT(accept()));
     connect(&search_buttonBox, SIGNAL(rejected()), this, SLOT(reject()));
-    connect(_session->get_device(), SIGNAL(device_updated()), this, SLOT(reject()));
 }
 
 Search::~Search()
diff --git a/DSView/pv/dialogs/waitingdialog.cpp b/DSView/pv/dialogs/waitingdialog.cpp
index 1be4bbe4..9cfda143 100644
--- a/DSView/pv/dialogs/waitingdialog.cpp
+++ b/DSView/pv/dialogs/waitingdialog.cpp
@@ -79,8 +79,7 @@ WaitingDialog::WaitingDialog(QWidget *parent, SigSession *session, int key) :
     connect(timer, SIGNAL(timeout()), this, SLOT(changeText()));
     connect(&_button_box, SIGNAL(accepted()), this, SLOT(accept()));
     connect(&_button_box, SIGNAL(rejected()), this, SLOT(reject()));
-    connect(_device_agent, SIGNAL(device_updated()), this, SLOT(stop()));
-
+    connect(_session->device_event_object(), SIGNAL(device_updated()), this, SLOT(stop()));
 
     QVBoxLayout *mlayout = new QVBoxLayout();
     mlayout->addWidget(warning_tips, Qt::AlignHCenter);
diff --git a/DSView/pv/dock/measuredock.cpp b/DSView/pv/dock/measuredock.cpp
index c5f8a6b7..d863a773 100644
--- a/DSView/pv/dock/measuredock.cpp
+++ b/DSView/pv/dock/measuredock.cpp
@@ -52,9 +52,7 @@ MeasureDock::MeasureDock(QWidget *parent, View &view, SigSession *session) :
     QScrollArea(parent),
     _session(session),
     _view(view)
-{
-    _session->add_msg_listener(this);
-    
+{     
     _widget = new QWidget(this);   
 
     _mouse_groupBox = new QGroupBox(_widget);
@@ -691,12 +689,5 @@ void MeasureDock::del_cursor()
     _view.update();
 }
 
-void MeasureDock::OnMessage(int msg)
-{
-    if (msg == DSV_MSG_DEVICE_OPTIONS_UPDATED){
-        this->reload();
-    }
-}
-
 } // namespace dock
 } // namespace pv
diff --git a/DSView/pv/dock/measuredock.h b/DSView/pv/dock/measuredock.h
index 37c316a5..a1a9369e 100644
--- a/DSView/pv/dock/measuredock.h
+++ b/DSView/pv/dock/measuredock.h
@@ -41,8 +41,7 @@
 
 #include <vector>
 
-#include "../ui/dscombobox.h"
-#include "../interface/icallbacks.h"
+#include "../ui/dscombobox.h" 
 
 namespace pv {
 
@@ -55,7 +54,7 @@ namespace view {
 
 namespace dock {
 
-class MeasureDock : public QScrollArea, public IMessageListener
+class MeasureDock : public QScrollArea
 {
     Q_OBJECT
 
@@ -78,9 +77,6 @@ private:
     DsComboBox* create_probe_selector(QWidget *parent);
     void update_probe_selector(DsComboBox *selector);
 
-    //IMessageListener
-    void OnMessage(int msg);
-
 private slots:
     void goto_cursor();
 
diff --git a/DSView/pv/dock/protocoldock.h b/DSView/pv/dock/protocoldock.h
index 38ddd13d..57069289 100644
--- a/DSView/pv/dock/protocoldock.h
+++ b/DSView/pv/dock/protocoldock.h
@@ -70,8 +70,7 @@ namespace dock {
 class ProtocolDock : public QScrollArea, 
 public IProtocolItemLayerCallback, 
 public IKeywordActive,
-public ISearchItemClick,
-public IMessageListener
+public ISearchItemClick
 {
     Q_OBJECT
 
diff --git a/DSView/pv/dock/searchdock.cpp b/DSView/pv/dock/searchdock.cpp
index 1bc914eb..7ec4fc27 100644
--- a/DSView/pv/dock/searchdock.cpp
+++ b/DSView/pv/dock/searchdock.cpp
@@ -51,12 +51,7 @@ SearchDock::SearchDock(QWidget *parent, View &view, SigSession *session) :
     QWidget(parent),
     _session(session),
     _view(view)
-{
-    connect(&_pre_button, SIGNAL(clicked()),
-        this, SLOT(on_previous()));
-    connect(&_nxt_button, SIGNAL(clicked()),
-        this, SLOT(on_next()));
-
+{ 
     _search_button = new QPushButton(this);
     _search_button->setFixedWidth(_search_button->height());
     _search_button->setDisabled(true);
@@ -85,6 +80,9 @@ SearchDock::SearchDock(QWidget *parent, View &view, SigSession *session) :
     setLayout(layout);
 
     retranslateUi();
+
+    connect(&_pre_button, SIGNAL(clicked()), this, SLOT(on_previous()));
+    connect(&_nxt_button, SIGNAL(clicked()),this, SLOT(on_next()));
 }
 
 SearchDock::~SearchDock()
@@ -248,6 +246,8 @@ void SearchDock::on_next()
 void SearchDock::on_set()
 {
     dialogs::Search dlg(this, _session, _pattern);
+    connect(_session->device_event_object(), SIGNAL(device_updated()), &dlg, SLOT(reject()));
+
     if (dlg.exec()) {
         std::map<uint16_t, QString> new_pattern = dlg.get_pattern();
 
diff --git a/DSView/pv/dock/searchdock.h b/DSView/pv/dock/searchdock.h
index d53c261e..a5178d56 100644
--- a/DSView/pv/dock/searchdock.h
+++ b/DSView/pv/dock/searchdock.h
@@ -67,6 +67,7 @@ public:
     ~SearchDock();
 
     void paintEvent(QPaintEvent *);
+
 private:
     void changeEvent(QEvent *event);
     void retranslateUi();
diff --git a/DSView/pv/dock/triggerdock.cpp b/DSView/pv/dock/triggerdock.cpp
index 8d3858c2..9f3f2db4 100644
--- a/DSView/pv/dock/triggerdock.cpp
+++ b/DSView/pv/dock/triggerdock.cpp
@@ -48,7 +48,6 @@ TriggerDock::TriggerDock(QWidget *parent, SigSession *session) :
     QScrollArea(parent),
     _session(session)
 {
-    session->add_msg_listener(this);
     
     _cur_ch_num = 16;
     if (_session->get_device()->have_instance()) {
@@ -309,8 +308,9 @@ bool TriggerDock::commit_trigger()
     // trigger mode update
     if (_simple_radioButton->isChecked()) {
         ds_trigger_set_mode(SIMPLE_TRIGGER);
-        return 0;
-    } else {
+        return false;
+    }
+    else {
         ds_trigger_set_en(true);
         if (_adv_tabWidget->currentIndex() == 0)
             ds_trigger_set_mode(ADV_TRIGGER);
@@ -402,7 +402,7 @@ bool TriggerDock::commit_trigger()
                                        _serial_bits_comboBox->currentText().toInt() - 1,
                                        0);
         }
-        return 1;
+        return true;
     }
 }
 
@@ -898,6 +898,8 @@ void TriggerDock::try_commit_trigger()
     int mode = _session->get_device()->get_work_mode();
     bool bInstant = _session->is_instant();
 
+    ds_trigger_reset();
+
     if (mode != LOGIC || bInstant){
         return;
     }
@@ -949,20 +951,5 @@ void TriggerDock::try_commit_trigger()
     }
 }
 
-void TriggerDock::OnMessage(int msg)
-{
-    switch (msg)
-    {
-    case DSV_MSG_DEVICE_OPTIONS_UPDATED:
-    case DSV_MSG_DEVICE_DURATION_UPDATED:
-    case DSV_MSG_CURRENT_DEVICE_CHANGED:
-        device_updated();
-        break;
-    case DSV_MSG_COLLECT_START_PREV:
-        try_commit_trigger();
-        break;
-    } 
-}
-
 } // namespace dock
 } // namespace pv
diff --git a/DSView/pv/dock/triggerdock.h b/DSView/pv/dock/triggerdock.h
index b599a01a..c02cad3e 100644
--- a/DSView/pv/dock/triggerdock.h
+++ b/DSView/pv/dock/triggerdock.h
@@ -42,8 +42,7 @@
 
 #include <vector>
 
-#include "../ui/dscombobox.h"
-#include "../interface/icallbacks.h"
+#include "../ui/dscombobox.h" 
 
 namespace pv {
 
@@ -51,7 +50,7 @@ class SigSession;
 
 namespace dock {
 
-class TriggerDock : public QScrollArea, public IMessageListener
+class TriggerDock : public QScrollArea
 {
     Q_OBJECT
 
@@ -69,6 +68,10 @@ public:
     QJsonObject get_session();
     void set_session(QJsonObject ses);
 
+    void device_updated();
+
+    void try_commit_trigger();
+
 private:
     void changeEvent(QEvent *event);
     void retranslateUi();
@@ -83,20 +86,14 @@ private:
      *        1: advanced trigger
      */
     bool commit_trigger();
-
-    void try_commit_trigger();
-
-    //IMessageListener
-    void OnMessage(int msg);
+ 
 
 public slots:
     void simple_trigger();
     void adv_trigger();
     void widget_enable(int index);
 
-    void value_changed();
-
-    void device_updated();
+    void value_changed(); 
 
 private:
     SigSession *_session;
diff --git a/DSView/pv/eventobject.cpp b/DSView/pv/eventobject.cpp
index b6f16060..5f5b9076 100644
--- a/DSView/pv/eventobject.cpp
+++ b/DSView/pv/eventobject.cpp
@@ -23,4 +23,8 @@
 
 EventObject::EventObject(){
     
+}
+
+DeviceEventObject::DeviceEventObject()
+{
 }
\ No newline at end of file
diff --git a/DSView/pv/eventobject.h b/DSView/pv/eventobject.h
index 1b13c2e5..e8d1fe9d 100644
--- a/DSView/pv/eventobject.h
+++ b/DSView/pv/eventobject.h
@@ -49,4 +49,17 @@ signals:
     void trigger_message(int msg);
 };
 
+
+class DeviceEventObject : public QObject
+{
+    Q_OBJECT
+
+public:
+    DeviceEventObject(); 
+
+
+signals: 
+    void device_updated();
+};
+
 #endif
\ No newline at end of file
diff --git a/DSView/pv/interface/icallbacks.h b/DSView/pv/interface/icallbacks.h
index 0b37c84f..e6cebb4b 100644
--- a/DSView/pv/interface/icallbacks.h
+++ b/DSView/pv/interface/icallbacks.h
@@ -23,23 +23,18 @@
 #ifndef _I_CALLBACKS_
 #define _I_CALLBACKS_
 
-struct ds_device_info;
 
 class ISessionCallback
 {
 public:
     virtual void show_error(QString error)=0;
     virtual void session_error()=0;
-    virtual void capture_state_changed(int state)=0;
-    virtual void device_detach()=0;
-
     virtual void session_save()=0;
     virtual void data_updated()=0;
     virtual void repeat_resume()=0;
     virtual void update_capture()=0;
-    virtual void cur_snap_samplerate_changed()=0;
 
-    virtual void device_setted()=0;
+    virtual void cur_snap_samplerate_changed()=0;
     virtual void signals_changed()=0;
     virtual void receive_trigger(quint64 trigger_pos)=0;
     virtual void frame_ended()=0;
@@ -53,8 +48,7 @@ public:
     
     virtual void receive_header()=0;
     virtual void data_received()=0;
-    virtual void trigger_message(int msg)=0;
-  
+    virtual void trigger_message(int msg)=0;  
 };
 
 class ISessionDataGetter
@@ -64,12 +58,26 @@ public:
 };
 
 
-#define DSV_MSG_DEVICE_LIST_UPDATE      4500
-#define DSV_MSG_COLLECT_START_PREV      5001
-#define DSV_MSG_COLLECT_START           5002
-#define DSV_MSG_COLLECT_END_PREV        5003
-#define DSV_MSG_COLLECT_END             5004
+class IDlgCallback
+{
+public:
+    virtual void OnDlgResult(bool bYes)=0;
+};
 
+class IMainForm{
+public:
+    virtual void switchLanguage(int language)=0;
+};
+
+
+#define DSV_MSG_START_COLLECT_WORK_PREV 5001
+#define DSV_MSG_START_COLLECT_WORK      5002
+#define DSV_MSG_COLLECT_START           5003
+#define DSV_MSG_COLLECT_END             5004
+#define DSV_MSG_END_COLLECT_WORK_PREV   5005
+#define DSV_MSG_END_COLLECT_WORK        5006
+
+#define DSV_MSG_DEVICE_LIST_UPDATED     6000
 #define DSV_MSG_BEGIN_DEVICE_OPTIONS    6001 //Begin show device options dialog.
 #define DSV_MSG_END_DEVICE_OPTIONS      6002
 #define DSV_MSG_DEVICE_OPTIONS_UPDATED  6003
@@ -78,6 +86,11 @@ public:
 #define DSV_MSG_CURRENT_DEVICE_CHANGE_PREV  6006
 #define DSV_MSG_CURRENT_DEVICE_CHANGED  6007
 #define DSV_MSG_NEW_USB_DEVICE          6008
+#define DSV_MSG_CURRENT_DEVICE_DETACHED 6009
+#define DSV_MSG_DEVICE_CONFIG_UPDATED   6010
+
+#define DSV_MSG_TRIG_NEXT_COLLECT       7001
+#define DSV_MSG_SAVE_COMPLETE           7002
 
 class IMessageListener
 {
diff --git a/DSView/pv/interface/uicallback.h b/DSView/pv/interface/uicallback.h
deleted file mode 100644
index b5dac050..00000000
--- a/DSView/pv/interface/uicallback.h
+++ /dev/null
@@ -1,33 +0,0 @@
-/*
- * This file is part of the DSView project.
- * DSView is based on PulseView.
- *
- * Copyright (C) 2021 DreamSourceLab <support@dreamsourcelab.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
- */
-
-#pragma once
-
-class IDlgCallback
-{
-public:
-    virtual void OnDlgResult(bool bYes)=0;
-};
-
-class IMainForm{
-public:
-    virtual void switchLanguage(int language)=0;
-};
diff --git a/DSView/pv/mainwindow.cpp b/DSView/pv/mainwindow.cpp
index d0d14e05..87fdc12e 100644
--- a/DSView/pv/mainwindow.cpp
+++ b/DSView/pv/mainwindow.cpp
@@ -100,9 +100,11 @@
 namespace pv
 {
 
-    MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent),
-                                              _msg(NULL)
-    {
+    MainWindow::MainWindow(QWidget *parent) 
+        : QMainWindow(parent)
+    {   
+        _msg = NULL;
+
         _session = AppControl::Instance()->GetSession();
         _session->set_callback(this);
         _device_agent = _session->get_device();
@@ -227,8 +229,7 @@ namespace pv
 
         retranslateUi();
 
-        // event
-        connect(&_event, SIGNAL(capture_state_changed(int)), this, SLOT(on_capture_state_changed(int)));
+        // event      
         connect(&_event, SIGNAL(session_error()), this, SLOT(on_session_error()));
         connect(&_event, SIGNAL(signals_changed()), this, SLOT(on_signals_changed()));
         connect(&_event, SIGNAL(receive_trigger(quint64)), this, SLOT(on_receive_trigger(quint64)));
@@ -285,11 +286,10 @@ namespace pv
         _search_dock->setWindowTitle(tr("Search..."));
     }
 
+/*
     void MainWindow::update_device_list()
     {
-        assert(_sampling_bar);
-
-        /*
+        assert(_sampling_bar); 
         if (!selected_device->name().contains("virtual")) {
             _file_bar->set_settings_en(true);
             _logo_bar->dsl_connected(true);
@@ -345,8 +345,9 @@ namespace pv
                     }
                 }
            }
-        */
+ 
     }
+    */
 
     void MainWindow::on_load_file(QString file_name)
     { 
@@ -368,54 +369,11 @@ namespace pv
         MsgBox::Show(NULL, error.toStdString().c_str(), this);
     }
  
- 
-   // void MainWindow::on_device_detach()
-    //{
-        /*
-
-        _device_agent->device_updated();
-
-        _session->set_repeating(false);
-        _session->stop_capture();
-        _sampling_bar->set_sampling(false);
-        _session->capture_state_changed(SigSession::Stopped);
-
-        session_save();
-        _view->hide_calibration();
-
-        if (_device_agent->get_work_mode() != DSO &&
-            strncmp(_device_agent->name().toUtf8(), "virtual", 7)) {
-            const auto logic_snapshot = _session->get_snapshot(SR_CHANNEL_LOGIC);
-            assert(logic_snapshot);
-            const auto analog_snapshot = _session->get_snapshot(SR_CHANNEL_ANALOG);
-            assert(analog_snapshot);
-
-            if (!logic_snapshot->empty() || !analog_snapshot->empty()) {
-                dialogs::DSMessageBox msg(this);
-                _msg = &msg;
-                msg.mBox()->setText(tr("Hardware Detached"));
-                msg.mBox()->setInformativeText(tr("Save captured data?"));
-                msg.mBox()->addButton(tr("Ok"), QMessageBox::AcceptRole);
-                msg.mBox()->addButton(tr("Cancel"), QMessageBox::RejectRole);
-                msg.mBox()->setIcon(QMessageBox::Warning);
-                if (msg.exec())
-                    on_save();
-                _msg = NULL;
-            }
-        }
-
-        _hot_detach = true;
-
-        if (!_session->get_saving())
-            device_detach_post();
-        */
-   // }
-
     void MainWindow::repeat_resume()
     {
-        while (_view->session().get_capture_state() == SigSession::Running)
-            QCoreApplication::processEvents();
-        _session->stop_capture();
+      //  while (_view->session().is_running_status())
+       //     QCoreApplication::processEvents();
+      //  _session->stop_capture();
     }
 
     void MainWindow::session_error()
@@ -478,7 +436,7 @@ namespace pv
 
         dialogs::DSMessageBox msg(this);
         
-        connect(_device_agent, SIGNAL(device_updated()), &msg, SLOT(accept()));
+        connect(_session->device_event_object(), SIGNAL(device_updated()), &msg, SLOT(accept()));
 
         QFont font("Monaco");
         font.setStyleHint(QFont::Monospace);
@@ -494,36 +452,6 @@ namespace pv
         _session->clear_error();
     }
 
-    void MainWindow::capture_state_changed(int state)
-    {
-        _event.capture_state_changed(state); // safe call
-    }
-
-    void MainWindow::on_capture_state_changed(int state)
-    {
-        if (!_session->repeat_check())
-        {
-            _file_bar->enable_toggle(state != SigSession::Running);
-            _sampling_bar->set_sampling(state == SigSession::Running);
-            _view->on_state_changed(state != SigSession::Running);
-
-            if (_device_agent->get_work_mode() != DSO ||
-                _session->get_instant())
-            {
-                _sampling_bar->enable_toggle(state != SigSession::Running);
-                _trig_bar->enable_toggle(state != SigSession::Running);
-                //_measure_dock->widget()->setEnabled(state != SigSession::Running);
-                _measure_widget->refresh();
-            }
-        }
-
-        if (state == SigSession::Stopped)
-        {
-            prgRate(0);
-            _view->repeat_unshow();
-        }
-    }
-
     void MainWindow::session_save()
     {
         QDir dir;
@@ -1072,10 +1000,16 @@ namespace pv
             switch (ke->key())
             {
             case Qt::Key_S:
-                on_run_stop();
+                if (_session->is_working())
+                    _session->stop_capture();
+                else
+                    _session->start_capture(false);
                 break;
             case Qt::Key_I:
-                on_instant_stop();
+                if (_session->is_working())
+                    _session->stop_capture();
+                else
+                    _session->start_capture(true);
                 break;
             case Qt::Key_T:
                 if (_device_agent->get_work_mode() == DSO)
@@ -1095,7 +1029,7 @@ namespace pv
                 on_search(!_search_dock->isVisible());
                 break;
             case Qt::Key_O:
-                _sampling_bar->on_configure();
+                _sampling_bar->config_device();
                 break;
             case Qt::Key_PageUp:
                 _view->set_scale_offset(_view->scale(),
@@ -1275,11 +1209,7 @@ namespace pv
     }
 
     /*------------------on event end-------*/
-
-    void MainWindow::device_setted()
-    {
-        _view->set_device();
-    }
+ 
 
     void MainWindow::signals_changed()
     {
@@ -1403,36 +1333,70 @@ namespace pv
     {
         switch (msg)
         {
-        case DSV_MSG_DEVICE_LIST_UPDATE: 
+        case DSV_MSG_DEVICE_LIST_UPDATED: 
             _sampling_bar->update_device_list();            
             break;
 
-        case DSV_MSG_COLLECT_START:
+        case DSV_MSG_START_COLLECT_WORK_PREV:
+            _trigger_widget->try_commit_trigger();
+            _view->capture_init();
+            break;
+
+        case DSV_MSG_START_COLLECT_WORK:
             _sampling_bar->set_sampling(false);
             break;
 
-        case DSV_MSG_COLLECT_END:
-            _sampling_bar->set_sampling(true);
+        case DSV_MSG_END_COLLECT_WORK:
+            _session->device_event_object()->device_updated();
+            _sampling_bar->set_sampling(true);           
             break;
+
         case DSV_MSG_NEW_USB_DEVICE:
             check_usb_device_speed();
             break;
 
         case DSV_MSG_CURRENT_DEVICE_CHANGED:
-            if (_msg != NULL)
+            if (_msg != NULL){
                 _msg->close();
+                _msg = NULL;
+            }
 
             _sampling_bar->update_device_list();
+            _view->reload();
+            _view->set_device();
             _trig_bar->reload();
             _sampling_bar->reload();
             _view->status_clear();
             _trigger_widget->init();
             _dso_trigger_widget->init();
-            _measure_widget->reload(); 
+            _measure_widget->reload();
+            _trigger_widget->device_updated();
             break;
 
         case DSV_MSG_CURRENT_DEVICE_CHANGE_PREV:
             _protocol_widget->del_all_protocol();
+            _view->reload();
+            break;
+
+        case DSV_MSG_DEVICE_OPTIONS_UPDATED:
+            _trigger_widget->device_updated();
+            _measure_widget->reload();
+            _view->check_calibration();
+            break;
+
+        case DSV_MSG_DEVICE_DURATION_UPDATED:
+            _trigger_widget->device_updated();
+            _view->timebase_changed();
+            break;
+
+        case DSV_MSG_DEVICE_MODE_CHANGED:
+            _view->mode_changed();        
+            break;
+
+        case DSV_MSG_CURRENT_DEVICE_DETACHED:
+            _session->device_event_object()->device_updated();
+             session_save();
+            _view->hide_calibration();            
             break;
         }
 }
diff --git a/DSView/pv/mainwindow.h b/DSView/pv/mainwindow.h
index bbf7a97c..e7c981ea 100644
--- a/DSView/pv/mainwindow.h
+++ b/DSView/pv/mainwindow.h
@@ -29,8 +29,7 @@
 #include <QTranslator> 
 #include "dialogs/dsmessagebox.h"
 #include "interface/icallbacks.h"
-#include "eventobject.h"
-#include "interface/uicallback.h"
+#include "eventobject.h" 
 #include <QJsonDocument>
 
 class QAction;
@@ -77,8 +76,12 @@ using namespace pv::device;
  
 //The mainwindow,referenced by MainFrame
 //TODO: create graph view,toolbar,and show device list
-class MainWindow : public QMainWindow, public ISessionCallback, 
-    public IMainForm, public ISessionDataGetter, public IMessageListener
+class MainWindow : 
+    public QMainWindow,
+    public ISessionCallback,
+    public IMainForm,
+    public ISessionDataGetter,
+    public IMessageListener
 {
 	Q_OBJECT
 
@@ -101,9 +104,7 @@ public slots:
 
 private slots:
 	void on_load_file(QString file_name);
-    void on_open_doc(); 
-  
-    void update_device_list();
+    void on_open_doc();  
   
     void on_protocol(bool visible);
     void on_trigger(bool visible);
@@ -116,8 +117,6 @@ private slots:
     void on_export();
     bool on_load_session(QString name);  
     bool on_store_session(QString name); 
-
-    void on_capture_state_changed(int state);
     void on_data_updated();
  
     void on_session_error();
@@ -149,14 +148,11 @@ private:
     //ISessionCallback
     void show_error(QString error);
     void session_error();
-    void capture_state_changed(int state);
-
     void data_updated();
     void repeat_resume();
     void update_capture();
     void cur_snap_samplerate_changed();
-    void device_setted();
-
+      
     void signals_changed();
     void receive_trigger(quint64 trigger_pos);
     void frame_ended();
@@ -171,8 +167,8 @@ private:
     void data_received();
     void trigger_message(int msg);
 
-     //ISessionDataGetter
-     bool genSessionData(std::string &str);
+    //ISessionDataGetter
+    bool genSessionData(std::string &str);
 
     bool gen_session_json(QJsonObject &sessionVar);
 
diff --git a/DSView/pv/sigsession.cpp b/DSView/pv/sigsession.cpp
index 057208e4..f2a608c1 100644
--- a/DSView/pv/sigsession.cpp
+++ b/DSView/pv/sigsession.cpp
@@ -80,11 +80,13 @@ SigSession::SigSession()
     _is_working = false;
     _is_repeat_mode = false;
     _is_saving = false; 
+    _device_status = ST_INIT;
   
     _noData_cnt = 0;
     _data_lock = false;
     _data_updated = false;
-    _active_last_device_flag = false;     
+    _is_auto_sel_device = false;
+    _is_trig_new_device_msg = false;
 
     this->add_msg_listener(this);
 
@@ -98,6 +100,8 @@ SigSession::SigSession()
     _bClose = false;
     _callback = NULL;  
 
+    _device_agent.set_callback(this);
+
     // Create snapshots & data containers 
     _logic_data = new data::Logic(new data::LogicSnapshot()); 
     _dso_data = new data::Dso(new data::DsoSnapshot()); 
@@ -156,6 +160,8 @@ bool SigSession::set_default_device()
     struct ds_device_info *array = NULL;
     int count = 0;
 
+    dsv_info("%s", "Set default device.");
+
     if (ds_get_device_list(&array, &count) != SR_OK)
     {
         dsv_err("%s", "Get device list error!");
@@ -192,6 +198,7 @@ bool SigSession::set_device(ds_device_handle dev_handle)
         return false;
     }
     _device_agent.update();
+    _device_status = ST_INIT;
 
     init_signals();
 
@@ -237,15 +244,21 @@ bool SigSession::set_file(QString name)
 }
 
 void SigSession::close_file(ds_device_handle dev_handle)
-{ 
-    assert(!_is_saving);
-    assert(!_is_working);
+{  
+    assert(dev_handle);
+    
+    if (dev_handle == _device_agent.handle() && _is_working){
+        dsv_err("%s", "The virtual device is running, can't remove it.");
+        return;
+    }
+    bool isCurrent = dev_handle == _device_agent.handle();
 
     if (ds_remove_device(dev_handle) != SR_OK){
         dsv_err("%s", "Remove virtual deivice error!");
     }
-    stop_capture();
-    set_default_device();
+
+   if (isCurrent)
+     set_default_device();
 }
 
 
@@ -416,15 +429,25 @@ void SigSession::container_init()
     }
 }
 
- void SigSession::start_capture(bool instant)
- {
-    assert(!_is_working);
+ bool SigSession::start_capture(bool instant)
+ { 
     assert(_callback);
 
+    dsv_info("%s", "Start collect.");
+
+    if (_is_working){
+        dsv_err("%s", "Error! Is working now.");
+        return false;
+    }
+
      // Check that a device instance has been selected.
     if (_device_agent.have_instance() == false) {
-        dsv_err("%s", "No device selected"); 
-        return;
+        dsv_err("%s", "Error!No device selected"); 
+        assert(false);
+    }
+    if (_device_agent.is_collecting()){
+        dsv_err("%s", "Error!Device is running.");
+        return false;
     }
 
     // update setting
@@ -432,17 +455,19 @@ void SigSession::container_init()
         _is_instant = true;
     else
         _is_instant = instant;
+    
+    _callback->trigger_message(DSV_MSG_START_COLLECT_WORK_PREV);
+
+    return exec_capture();
  }
 
-void SigSession::exec_capture()
+bool SigSession::exec_capture()
 {   
-    if (_device_agent.is_running()){
-        dsv_err("%s", "Device is running.");
-        assert(false);
+    if (_device_agent.is_collecting()){
+        dsv_err("%s", "Error!Device is running.");
+        return false;
     }
-
-    _callback->trigger_message(DSV_MSG_COLLECT_START_PREV);
-
+ 
     // stop all decode tasks
     int run_dex = 0;
     clear_all_decode_task(run_dex);
@@ -453,30 +478,33 @@ void SigSession::exec_capture()
         view::DsoSignal *dsoSig = NULL;
         if ((dsoSig = dynamic_cast<view::DsoSignal*>(s)))
             dsoSig->set_mValid(false);
-    }     
-
-    capture_init();
+    }
 
     if (_device_agent.have_enabled_channel() == false){
         _callback->show_error("No probes enabled.");
-        data_updated(); 
-        _is_working = false;
-        return;
+        return false;
     }
+
+    capture_init(); 
  
     if (_device_agent.start() == false)
     {
         dsv_err("%s", "Start collect error!");
+        return false;
     }
-
+    
     _is_working = true;
+    _callback->trigger_message(DSV_MSG_START_COLLECT_WORK);
+    return true;
 }
 
 void SigSession::stop_capture()
 {
-    assert(_is_working);
-  
-    data_unlock();
+    dsv_info("%s", "Stop collect.");
+
+    if (!_is_working){
+        return;
+    }
 
     bool wait_upload = false;
     if (!_is_repeat_mode) {
@@ -488,7 +516,7 @@ void SigSession::stop_capture()
     }
     if (!wait_upload) {
         _is_working = false;        
-        _callback->trigger_message(DSV_MSG_COLLECT_END_PREV); 
+        _callback->trigger_message(DSV_MSG_END_COLLECT_WORK_PREV); 
         exit_capture();
     }
     else{
@@ -500,7 +528,7 @@ void SigSession::exit_capture()
 {  
     _is_instant = false;
 
-    if (_device_agent.is_running()){       
+    if (_device_agent.is_collecting()){
         _device_agent.stop();
     }
 }
@@ -550,20 +578,12 @@ std::set<data::SignalData*> SigSession::get_data()
 
     return data;
 }
-
-void SigSession::set_capture_state(capture_state state)
-{ 
-    std::lock_guard<std::mutex> lock(_sampling_mutex);
-    _capture_state = state;
-    data_updated();
-    capture_state_changed(state);
-}
  
 void SigSession::check_update()
 {
     ds_lock_guard lock(_data_mutex);
 
-    if (_device_agent.is_running() == false)
+    if (_device_agent.is_collecting() == false)
         return;
 
     if (_data_updated) {
@@ -742,8 +762,8 @@ void SigSession::reload()
         assert(false);
     }
 
-    if (_capture_state == Running)
-        stop_capture();
+    if (_is_working)
+        return;
 
     std::vector<view::Signal*> sigs;
     view::Signal *signal = NULL;
@@ -901,9 +921,6 @@ void SigSession::feed_in_meta(const sr_dev_inst *sdi,
             /// @todo handle samplerate changes
             /// samplerate = (uint64_t *)src->value;
             break;
-        default:
-            // Unknown metadata is not an error.
-            break;
         }
     }
 }
@@ -1065,7 +1082,8 @@ void SigSession::feed_in_analog(const sr_datafeed_analog &analog)
 
         // first payload
         _analog_data->snapshot()->first_payload(analog, _device_agent.get_sample_limit(), _device_agent.get_channels());
-    } else {
+    }
+    else {
         // Append to the existing data snapshot
         _analog_data->snapshot()->append_payload(analog);
     }
@@ -1358,18 +1376,17 @@ void SigSession::rst_decoder(int index)
     }
 }
 
- void SigSession::rst_decoder_by_key_handel(void *handel)
- { 
-     int dex = get_trace_index_by_key_handel(handel);
-     rst_decoder(dex);
- }
-  
+void SigSession::rst_decoder_by_key_handel(void *handel)
+{
+    int dex = get_trace_index_by_key_handel(handel);
+    rst_decoder(dex);
+}
+
 pv::data::DecoderModel* SigSession::get_decoder_model()
 {
     return _decoder_model;
 }
 
-
 void SigSession::spectrum_rebuild()
 {
     bool has_dso_signal = false;
@@ -1539,9 +1556,7 @@ void SigSession::set_repeat_intvl(double interval)
 
 bool SigSession::repeat_check()
 {
-    if (_device_agent.is_running() ||
-        get_run_mode() != Repetitive ||
-        !isRepeating()) {
+    if (!_is_working) {
         return false;
     }
 
@@ -1557,7 +1572,7 @@ bool SigSession::repeat_check()
 
 void SigSession::repeat_update()
 {
-    if (isRepeating()) {
+    if (!_is_instant && _is_working && _is_repeat_mode) {
         _repeat_hold_prg -= 100/RepeatHoldDiv;
         if (_repeat_hold_prg != 0){
             _out_timer.TimeOut(_repeat_intvl * 1000 / RepeatHoldDiv, std::bind(&SigSession::repeat_update, this));
@@ -1570,7 +1585,7 @@ void SigSession::repeat_update()
 
 int SigSession::get_repeat_hold()
 {
-    if (isRepeating())
+    if (!_is_instant && _is_working && _is_repeat_mode) 
         return _repeat_hold_prg;
     else
         return 0;
@@ -1626,21 +1641,21 @@ void SigSession::set_stop_scale(float scale)
     _stop_scale = scale;
 }
 
- void SigSession::Open()
- {      
- }
+void SigSession::Open()
+{
+}
 
- void SigSession::Close()
- { 
-     if (_bClose)
+void SigSession::Close()
+{
+    if (_bClose)
         return;
 
-     _bClose = true; 
-     stop_capture();
+    _bClose = true;
+    exit_capture();
 
-     // TODO: This should not be necessary
-     _session = NULL;
- }
+    // TODO: This should not be necessary
+    _session = NULL;
+}
 
 //append a decode task, and try create a thread
  void SigSession::add_decode_task(view::DecodeTrace *trace)
@@ -1781,85 +1796,109 @@ void SigSession::set_stop_scale(float scale)
       _is_decoding = false;
   }
 
-  Snapshot* SigSession::get_signal_snapshot()
+  Snapshot *SigSession::get_signal_snapshot()
   {
-    int mode = _device_agent.get_work_mode();
-    if (mode == ANALOG)
-        return _analog_data->snapshot();
-    else if (mode == DSO)
-        return _dso_data->snapshot();
-    else
-        return _logic_data->snapshot();
+      int mode = _device_agent.get_work_mode();
+      if (mode == ANALOG)
+          return _analog_data->snapshot();
+      else if (mode == DSO)
+          return _dso_data->snapshot();
+      else
+          return _logic_data->snapshot();
   }
 
   void SigSession::device_lib_event_callback(int event)
   {
-     if (_session == NULL){
-         dsv_err("%s", "Error!Global variable \"_session\" is null.");
-         return;
-    }
-    _session->on_device_lib_event(event);
+      if (_session == NULL)
+      {
+          dsv_err("%s", "Error!Global variable \"_session\" is null.");
+          return;
+      }
+      _session->on_device_lib_event(event);
   }
 
 void SigSession::on_device_lib_event(int event)
 { 
-    if (event == DS_EV_COLLECT_TASK_START){
+    switch (event)
+    {
+    case DS_EV_DEVICE_RUNNING:
+        _device_status = ST_RUNNING;
+        break;
+        
+    case DS_EV_DEVICE_STOPPED:
+        _device_status = ST_STOPPED;
+        break;
+
+    case DS_EV_COLLECT_TASK_START:        
         _callback->trigger_message(DSV_MSG_COLLECT_START);
-        return;
-    }
-    
-    if (event == DS_EV_COLLECT_TASK_END){
-        _callback->trigger_message(DSV_MSG_COLLECT_END);
+        break;
 
-        if (_logic_data->snapshot()->last_ended() == false)
-            dsv_err("%s", "The collected data is error!"); 
-         if (_dso_data->snapshot()->last_ended() == false)
-            dsv_err("%s", "The collected data is error!");                
-         if (_analog_data->snapshot()->last_ended() == false)
-            dsv_err("%s", "The collected data is error!");  
-
-        bool bInstant = _is_instant;
-        _is_instant = false;
-
-        if (!bInstant && _is_repeat_mode){
-            if (_repeat_intvl > 0)
-                _repeate_timer.Start(_repeat_intvl * 1000);
-            else
-                this->exec_capture();
-        }        
-         
-        return;
-    }
-
-    if (event == DS_EV_NEW_DEVICE_ATTACH || event == DS_EV_CURRENT_DEVICE_DETACH)
-    {
-        if (_is_working)
-            this->stop_capture();
- 
-
-        if (have_hardware_data())
+    case DS_EV_COLLECT_TASK_END:
+    case DS_EV_COLLECT_TASK_END_BY_ERROR:
+    case DS_EV_COLLECT_TASK_END_BY_DETACHED:
         {
-            // Try to save current device data, and auto select the lastest device later.
-            _active_last_device_flag = true;
-            if (!_is_saving)
-                store_session_data();
-            return;
+            _callback->trigger_message(DSV_MSG_COLLECT_END);
+
+            if (_logic_data->snapshot()->last_ended() == false)
+                dsv_err("%s", "The collected data is error!"); 
+            if (_dso_data->snapshot()->last_ended() == false)
+                dsv_err("%s", "The collected data is error!");                
+            if (_analog_data->snapshot()->last_ended() == false)
+                dsv_err("%s", "The collected data is error!");  
+
+            // trigger next collect
+            if (!_is_instant 
+                && _is_repeat_mode 
+                && _is_working 
+                && event == DS_EV_COLLECT_TASK_END)
+            {
+                _callback->trigger_message(DSV_MSG_TRIG_NEXT_COLLECT);
+            }
+            else{
+                _is_working = false;
+                _is_instant = false;
+                _callback->trigger_message(DSV_MSG_END_COLLECT_WORK);
+            }
         }
-    }
+        break;
 
-    if (_is_working)
-            this->stop_capture(); 
+    case DS_EV_NEW_DEVICE_ATTACH:
+    case DS_EV_CURRENT_DEVICE_DETACH:
+        {
+            if (_is_working)
+                stop_capture();
 
-    if (event == DS_EV_NEW_DEVICE_ATTACH || event == DS_EV_CURRENT_DEVICE_DETACH)
-    {
-        if (_is_saving)
-            _active_last_device_flag = true; //Auto switch device after save data.
-        else
-             set_default_device();
-    }
-    else
-    {
-        _callback->trigger_message(DSV_MSG_DEVICE_LIST_UPDATE); // Update list only.
+            if (DS_EV_CURRENT_DEVICE_DETACH == event){
+                _callback->trigger_message(DSV_MSG_CURRENT_DEVICE_DETACHED);
+            }
+
+            int work_mode = _device_agent.get_work_mode();
+
+            if (have_hardware_data() && (work_mode == LOGIC || work_mode == ANALOG))
+            {
+                // Try to save current device data, and auto select the lastest device later.
+                _is_auto_sel_device = true;
+                if (!_is_saving)
+                    store_session_data();
+
+                _is_trig_new_device_msg = DS_EV_NEW_DEVICE_ATTACH == event;
+            }
+            else{
+                set_default_device();
+
+                if (DS_EV_NEW_DEVICE_ATTACH == event)
+                    _callback->trigger_message(DSV_MSG_NEW_USB_DEVICE);
+            }
+        }
+        break;
+
+    case DS_EV_INACTIVE_DEVICE_DETACH:
+        _callback->trigger_message(DSV_MSG_DEVICE_LIST_UPDATED); // Update list only.
+        break;
+
+    default:
+        dsv_err("%s", "Error!Unknown device event.");
+        break;
     }
 }
 
@@ -1879,22 +1918,54 @@ void SigSession::on_device_lib_event(int event)
   void SigSession::set_repeat_mode(bool repeat)
   {
      assert(!_is_working);
-     assert(_is_repeat_mode != repeat);
-     _is_repeat_mode = repeat;     
-     _repeat_hold_prg = 0;
+
+     if(_is_repeat_mode != repeat)
+     {
+        _is_repeat_mode = repeat;     
+        _repeat_hold_prg = 0;
+     }    
   }
 
   void SigSession::repeat_capture_wait_timout()
   {
-
+     exec_capture();
   }
 
   void SigSession::OnMessage(int msg)
   {
-    if (msg == DSV_MSG_DEVICE_OPTIONS_UPDATED){
-        this->reload();
+    switch (msg)
+    {
+    case DSV_MSG_DEVICE_OPTIONS_UPDATED:
+        reload();
+        break;
+
+    case DSV_MSG_TRIG_NEXT_COLLECT:
+        if (_repeat_intvl > 0)
+                _repeate_timer.Start(_repeat_intvl * 1000);
+            else
+                exec_capture();
+        break;
+    
+    case DSV_MSG_SAVE_COMPLETE:
+        bool ret = false;
+        if (_is_auto_sel_device)
+            ret = set_default_device();
+        if (ret && _is_trig_new_device_msg){
+            _callback->trigger_message(DSV_MSG_NEW_USB_DEVICE);
+        }
+        break;
     }
   }
 
+  void SigSession::DeviceConfigChanged()
+  {
+
+  }
+
+  void SigSession::store_session_data()
+  {
+
+  }
+
   
 } // namespace pv
diff --git a/DSView/pv/sigsession.h b/DSView/pv/sigsession.h
index 3c0ad75e..6a90a69a 100644
--- a/DSView/pv/sigsession.h
+++ b/DSView/pv/sigsession.h
@@ -38,6 +38,7 @@
 #include "dstimer.h"
 #include <libsigrok.h>
 #include "deviceagent.h"
+#include "eventobject.h"
  
 
 struct srd_decoder;
@@ -85,7 +86,9 @@ using namespace pv::device;
 using namespace pv::data;
 
 //created by MainWindow
-class SigSession: public IMessageListener
+class SigSession:
+    public IMessageListener,
+    public IDeviceAgentCallback
 {
 private:
     static constexpr float Oversampling = 2.0f;
@@ -107,6 +110,12 @@ public:
         Data_overflow
     };
 
+    enum device_status_type{
+        ST_INIT = 0,
+        ST_RUNNING = 1,
+        ST_STOPPED = 2,
+    };
+
 private:
     SigSession(SigSession &o);
   
@@ -128,7 +137,7 @@ public:
     bool set_device(ds_device_handle dev_handle);   
     bool set_file(QString name);
     void close_file(ds_device_handle dev_handle);
-    void start_capture(bool instant);
+    bool start_capture(bool instant);
     void stop_capture();    
 	 
     uint64_t cur_samplerate();
@@ -226,14 +235,27 @@ public:
         return _is_working;
     }
 
+    inline bool is_init_status(){
+        return _device_status == ST_INIT;
+    }
+
+    // The collect thread is running.
+    inline bool is_running_status(){
+        return _device_status == ST_RUNNING;
+    }
+
+    inline bool is_stopped_status(){
+        return _device_status == ST_STOPPED;
+    }
+
     void set_repeat_mode(bool repeat);
 
     inline bool is_repeat_mode(){
         return _is_repeat_mode;
-    } 
- 
-    inline void capture_state_changed(int state){
-        _callback->capture_state_changed(state);
+    }
+
+    inline bool is_repeating(){
+        return _is_repeat_mode && !_is_instant;
     }
 
     inline void session_save(){
@@ -259,6 +281,10 @@ public:
     inline void set_saving(bool flag){
         _is_saving = flag;
     }
+
+    inline DeviceEventObject* device_event_object(){
+        return &_device_event;
+    }
    
     void reload();
     void refresh(int holdtime);  
@@ -272,7 +298,7 @@ public:
     void broadcast_msg(int msg);
 
 private:
-    void exec_capture();
+    bool exec_capture();
     void exit_capture();
 
     inline void data_updated(){
@@ -307,6 +333,9 @@ private:
     //IMessageListener
     void OnMessage(int msg);
 
+    //IDeviceAgentCallback
+    void DeviceConfigChanged();
+
 private:
     /**
      * Attempts to autodetect the format. Failing that
@@ -315,8 +344,7 @@ private:
      * 	used, or NULL if no input format was selected or
      * 	auto-detected.
      */
-    static sr_input_format* determine_input_file_format(const std::string &filename);  
- 
+    static sr_input_format* determine_input_file_format(const std::string &filename); 
 
     // data feed
 	void feed_in_header(const sr_dev_inst *sdi);
@@ -383,7 +411,7 @@ private:
     bool        _dso_feed;
     float       _stop_scale; 
     bool        _bClose; 
-    bool        _active_last_device_flag;
+    bool        _is_auto_sel_device;
  
     uint64_t    _save_start;
     uint64_t    _save_end; 
@@ -393,10 +421,13 @@ private:
     int         _repeat_hold_prg; // The time sleep progress
     bool        _is_saving;
     bool        _is_instant;
+    bool        _is_trig_new_device_msg;
+    int         _device_status;
 
     ISessionCallback *_callback;
     DeviceAgent   _device_agent;
     std::vector<IMessageListener*> _msg_listeners;
+    DeviceEventObject   _device_event;
    
 private:
 	// TODO: This should not be necessary. Multiple concurrent
diff --git a/DSView/pv/toolbars/filebar.cpp b/DSView/pv/toolbars/filebar.cpp
index 798f6966..cc12c0cc 100644
--- a/DSView/pv/toolbars/filebar.cpp
+++ b/DSView/pv/toolbars/filebar.cpp
@@ -242,10 +242,5 @@ void FileBar::set_settings_en(bool enable)
     _menu_session->setDisabled(!enable);
 }
 
-void FileBar::OnMessage(int msg)
-{
-
-}
-
 } // namespace toolbars
 } // namespace pv
diff --git a/DSView/pv/toolbars/filebar.h b/DSView/pv/toolbars/filebar.h
index 243e4501..5b3c435f 100644
--- a/DSView/pv/toolbars/filebar.h
+++ b/DSView/pv/toolbars/filebar.h
@@ -28,15 +28,14 @@
 #include <QAction>
 #include <QMenu>
 
-#include "../sigsession.h"
-#include "../interface/icallbacks.h"
+#include "../sigsession.h" 
 
 namespace pv {
 namespace toolbars {
 
 //toolbar button,referenced by MainWindow
 //TODO: load session file, sorte session, load log data file, sorte data, export data
-class FileBar : public QToolBar, public IMessageListener
+class FileBar : public QToolBar
 {
     Q_OBJECT
 
@@ -67,9 +66,6 @@ private slots:
     void on_actionOpen_triggered();
     void on_actionCapture_triggered();
 
-    //IMessageListener
-    void OnMessage(int msg);
-
 private:
     bool _enable;
     SigSession* _session;
diff --git a/DSView/pv/toolbars/logobar.h b/DSView/pv/toolbars/logobar.h
index 4637cdac..e4c49ccc 100644
--- a/DSView/pv/toolbars/logobar.h
+++ b/DSView/pv/toolbars/logobar.h
@@ -30,7 +30,7 @@
 #include <libsigrok.h> 
 
 #include "../sigsession.h"
-#include "../interface/uicallback.h"
+#include "../interface/icallbacks.h"
 
 
 namespace pv {
diff --git a/DSView/pv/toolbars/samplingbar.cpp b/DSView/pv/toolbars/samplingbar.cpp
index 5f24d31d..3269d5af 100644
--- a/DSView/pv/toolbars/samplingbar.cpp
+++ b/DSView/pv/toolbars/samplingbar.cpp
@@ -64,8 +64,7 @@ SamplingBar::SamplingBar(SigSession *session, QWidget *parent) :
     _updating_device_list = false;
     _updating_sample_rate = false;
     _updating_sample_count = false;
-    _sampling = false;
-    _enable = true; 
+
     _last_device_handle = NULL_HANDLE;
 
     _session = session;
@@ -168,15 +167,17 @@ void SamplingBar::retranslateUi()
 
    int mode = _device_agent->get_work_mode();
 
+   bool is_working = _session->is_working();
+
     if (_session->is_instant()) {
         if (bDev && mode == DSO)
-            _instant_button.setText(_sampling ? tr("Stop") : tr("Single"));
+            _instant_button.setText(is_working ? tr("Stop") : tr("Single"));
         else
-            _instant_button.setText(_sampling ? tr("Stop") : tr("Instant"));
+            _instant_button.setText(is_working ? tr("Stop") : tr("Instant"));
         _run_stop_button.setText(tr("Start"));
     }
     else {
-        _run_stop_button.setText(_sampling ? tr("Stop") : tr("Start"));
+        _run_stop_button.setText(is_working ? tr("Stop") : tr("Start"));
         if (bDev && mode == DSO)
             _instant_button.setText(tr("Single"));
         else
@@ -215,10 +216,10 @@ void SamplingBar::reStyle()
     if (true) {
         QString iconPath = GetIconPath();
         _configure_button.setIcon(QIcon(iconPath+"/params.svg"));
-        _mode_button.setIcon(_session->get_run_mode() == pv::SigSession::Single ? QIcon(iconPath+"/modes.svg") :
-                                                                                 QIcon(iconPath+"/moder.svg"));
-        _run_stop_button.setIcon(_sampling ? QIcon(iconPath+"/stop.svg") :
-                                             QIcon(iconPath+"/start.svg"));
+        QString icon1 = _session->is_repeat_mode() ? "moder.svg" : "modes.svg";
+        _mode_button.setIcon(QIcon(iconPath+ "/" + icon1));
+        QString icon2 = _session->is_working() ? "stop.svg" : "start.svg";
+        _run_stop_button.setIcon(QIcon(iconPath + "/" + icon2));
         _instant_button.setIcon(QIcon(iconPath+"/single.svg"));
         _action_single->setIcon(QIcon(iconPath+"/oneloop.svg"));
         _action_repeat->setIcon(QIcon(iconPath+"/repeat.svg"));
@@ -237,6 +238,8 @@ void SamplingBar::on_configure()
     _session->broadcast_msg(DSV_MSG_BEGIN_DEVICE_OPTIONS);
 
     pv::dialogs::DeviceOptions dlg(this);
+    connect(_session->device_event_object(), SIGNAL(device_updated()), &dlg, SLOT(reject()));
+
     ret = dlg.exec();
 
     if (ret == QDialog::Accepted) 
@@ -298,7 +301,7 @@ void SamplingBar::zero_adj()
     _sample_count.setCurrentIndex(i);
     commit_hori_res();
 
-    if (_session->is_running() == false)
+    if (_session->is_working() == false)
         _session->start_capture(true);
 
     pv::dialogs::WaitingDialog wait(this, _session, SR_CONF_ZERO);
@@ -310,7 +313,7 @@ void SamplingBar::zero_adj()
         }
     }
 
-    if (_session->is_running())
+    if (_session->is_working())
         _session->stop_capture();
 
     _sample_count.setCurrentIndex(index_back);
@@ -318,9 +321,7 @@ void SamplingBar::zero_adj()
 }
 
 void SamplingBar::set_sampling(bool sampling)
-{ 
-    _sampling = sampling;
-
+{  
     if (!sampling) {
         enable_run_stop(true);
         enable_instant(true);
@@ -344,7 +345,7 @@ void SamplingBar::set_sampling(bool sampling)
         else
             _run_stop_button.setIcon(sampling ? QIcon(iconPath+"/stop.svg") : QIcon(iconPath+"/start.svg"));
   
-        _mode_button.setIcon(_session->get_run_mode() == pv::SigSession::Single ? QIcon(iconPath+"/modes.svg") :
+        _mode_button.setIcon(_session->is_repeat_mode() == false ? QIcon(iconPath+"/modes.svg") :
                                                                              QIcon(iconPath+"/moder.svg"));
     }
 
@@ -370,8 +371,12 @@ void SamplingBar::update_sample_rate_selector()
 	const uint64_t *elements = NULL;
 	gsize num_elements;
 
-    if (_updating_sample_rate)
+    dsv_info("%s", "Update rate list.");
+
+    if (_updating_sample_rate){
+        dsv_err("%s", "Error! The rate list is updating.");
         return;
+    }
 
     disconnect(&_sample_rate, SIGNAL(currentIndexChanged(int)),
         this, SLOT(on_samplerate_sel(int)));
@@ -384,7 +389,7 @@ void SamplingBar::update_sample_rate_selector()
     _updating_sample_rate = true;
 
     gvar_dict = _device_agent->get_config_list(NULL, SR_CONF_SAMPLERATE);
-    if (gvar_dict != NULL)
+    if (gvar_dict == NULL)
     {
         _sample_rate.clear();
         _sample_rate.show();
@@ -429,12 +434,9 @@ void SamplingBar::update_sample_rate_selector_value()
 {
     if (_updating_sample_rate)
         return;
-
-    const uint64_t samplerate = _device_agent->get_sample_rate();
-
-    assert(!_updating_sample_rate);
     _updating_sample_rate = true;
 
+    const uint64_t samplerate = _device_agent->get_sample_rate();  
     uint64_t cur_value = _sample_rate.itemData(_sample_rate.currentIndex()).value<uint64_t>();
 
     if (samplerate != cur_value) {
@@ -469,8 +471,12 @@ void SamplingBar::update_sample_count_selector()
     double duration;
     bool rle_support = false;
 
-    if (_updating_sample_count)
+    dsv_info("%s", "Update sample count list.");
+
+    if (_updating_sample_count){
+        dsv_err("%s", "Error! The sample count is updating.");
         return;
+    }
 
     disconnect(&_sample_count, SIGNAL(currentIndexChanged(int)),
         this, SLOT(on_samplecount_sel(int)));
@@ -782,8 +788,8 @@ void SamplingBar::commit_settings()
 //start or stop capture
 void SamplingBar::on_run_stop()
 {
-    if (get_sampling() || _session->isRepeating()) {
-        _session->exit_capture();
+    if (_session->is_working()) {
+        _session->stop_capture();
         return;
     }
 
@@ -792,9 +798,7 @@ void SamplingBar::on_run_stop()
         dsv_info("%s", "Have no device, can't to collect data.");
         return;
     }
-   
-    enable_run_stop(false);
-    enable_instant(false);
+    
     commit_settings(); 
 
     if (_device_agent->get_work_mode() == DSO) {
@@ -825,16 +829,20 @@ void SamplingBar::on_run_stop()
             }
         }
     }
- 
+
+    if (_session->start_capture(false)){
+         enable_run_stop(false);
+        enable_instant(false);
+    } 
 }
 
 void SamplingBar::on_instant_stop()
 {
-    if (get_sampling()) {
-        _session->set_repeating(false);
+    if (_session->is_working()) {
+        _session->set_repeat_mode(false);
         bool wait_upload = false;
 
-        if (_session->get_run_mode() != SigSession::Repetitive) {
+        if (_session->is_repeat_mode() == false) {
             GVariant *gvar = _device_agent->get_config(NULL, NULL, SR_CONF_WAIT_UPLOAD);
             if (gvar != NULL) {
                 wait_upload = g_variant_get_boolean(gvar);
@@ -843,24 +851,17 @@ void SamplingBar::on_instant_stop()
         }
         if (!wait_upload) {
             _session->stop_capture();
-            _session->capture_state_changed(SigSession::Stopped);
         }
     } 
     else {
 
         if (_device_agent->have_instance() == false){
-            dsv_info("%s", "Have no device, can't to collect data.");
+            dsv_info("%s", "Error! Have no device, can't to collect data.");
             return;
         }
-
-        enable_run_stop(false);
-        enable_instant(false);
+ 
         commit_settings(); 
 
-        if (_device_agent->have_instance() == false){
-            return;
-        }
-
         if (_device_agent->get_work_mode() == DSO) {
             GVariant* gvar = _device_agent->get_config(NULL, NULL, SR_CONF_ZERO);
 
@@ -888,7 +889,13 @@ void SamplingBar::on_instant_stop()
                     return;
                 }
             }
-        } 
+        }
+
+        if (_session->start_capture(true))
+        {
+            enable_run_stop(false);
+            enable_instant(false);
+        }
     }
 }
 
@@ -991,13 +998,19 @@ void SamplingBar::on_mode()
 
     if (act == _action_single) {
         _mode_button.setIcon(QIcon(iconPath+"/modes.svg"));
-        _session->set_run_mode(pv::SigSession::Single);
+        _session->set_repeat_mode(false);
     }
     else if (act == _action_repeat) {
         _mode_button.setIcon(QIcon(iconPath+"/moder.svg"));
-        pv::dialogs::Interval interval_dlg(_session, this);
+        pv::dialogs::Interval interval_dlg(this);
+
+        interval_dlg.set_interval(_session->get_repeat_intvl());
         interval_dlg.exec();
-        _session->set_run_mode(pv::SigSession::Repetitive);
+
+        if (interval_dlg.is_done()){
+           _session->set_repeat_intvl(interval_dlg.get_interval());
+           _session->set_repeat_mode(true);
+        }       
     }
 }
 
@@ -1007,6 +1020,8 @@ void SamplingBar::on_mode()
     int dev_count = 0;
     int select_index = 0;
 
+    dsv_info("%s", "Update device list.");
+
     array = _session->get_device_list(dev_count, select_index);
 
     if (array == NULL){
@@ -1026,7 +1041,6 @@ void SamplingBar::on_mode()
     free(array);
 
     _device_selector.setCurrentIndex(select_index);
-
     update_sample_rate_selector();
 
     int width = _device_selector.sizeHint().width();
@@ -1036,19 +1050,9 @@ void SamplingBar::on_mode()
     _updating_device_list = false;
   }
 
-  void SamplingBar::OnMessage(int msg)
-  { 
-    switch (msg)
-    {
-    case DSV_MSG_DEVICE_LIST_UPDATE:
-    case DSV_MSG_CURRENT_DEVICE_CHANGED:
-        update_device_list();
-        break;
-    case DSV_MSG_COLLECT_START:
-        set_sampling(false);
-    case DSV_MSG_COLLECT_END:
-        set_sampling(true);    
-    }
+  void SamplingBar::config_device()
+  {
+        on_configure();
   }
 
 } // namespace toolbars
diff --git a/DSView/pv/toolbars/samplingbar.h b/DSView/pv/toolbars/samplingbar.h
index 6a492ffd..36182864 100644
--- a/DSView/pv/toolbars/samplingbar.h
+++ b/DSView/pv/toolbars/samplingbar.h
@@ -33,6 +33,7 @@
 #include <QAction>
 #include <QMenu>
 #include "../ui/dscombobox.h"
+#include <QDialog>
 
 struct st_dev_inst;
 class QAction;
@@ -75,9 +76,8 @@ namespace pv
  
 
         public:
-            SamplingBar(SigSession *session, QWidget *parent);
-            
-            void update_sample_rate_selector();
+            SamplingBar(SigSession *session, QWidget *parent);            
+           
             void enable_toggle(bool enable);           
             void enable_instant(bool enable);
 
@@ -85,9 +85,11 @@ namespace pv
             double commit_hori_res();
             double get_hori_res(); 
             void set_sample_rate(uint64_t sample_rate);
-            void update_device_list();
-            void set_sampling(bool sampling);
+            void update_device_list();          
             void reload();
+            void set_sampling(bool sampling);
+
+            void config_device(); 
 
         private:
             void enable_run_stop(bool enable);
@@ -95,15 +97,13 @@ namespace pv
             void retranslateUi();
             void reStyle();
 
+            void update_sample_rate_selector();
             void update_sample_rate_selector_value();
             void update_sample_count_selector();
             void update_sample_count_selector_value();
             void commit_settings();
             void setting_adj();
 
-            //IMessageListener
-            void OnMessage(int msg);
-
         private slots:
             void on_mode();
             void on_run_stop();
@@ -116,18 +116,18 @@ namespace pv
            
 
         private:
-            SigSession          *_session; 
-            bool                _enable;
-            bool                _sampling;
+            SigSession          *_session;  
 
-            QToolButton         _device_type;
+            QToolButton          _device_type;
             DsComboBox           _device_selector;  
 
-            QToolButton         _configure_button;
+            QToolButton          _configure_button;
             DsComboBox           _sample_count;
             DsComboBox           _sample_rate;
+
             bool                _updating_sample_rate;
             bool                _updating_sample_count;
+            bool                _updating_device_list;
 
             QToolButton         _run_stop_button;
             QToolButton         _instant_button;
@@ -139,7 +139,7 @@ namespace pv
             QMenu               *_mode_menu;
             QAction             *_action_repeat;
             QAction             *_action_single;
-            bool                _updating_device_list;
+        
             DeviceAgent         *_device_agent;
             ds_device_handle    _last_device_handle;
         };
diff --git a/DSView/pv/view/analogsignal.cpp b/DSView/pv/view/analogsignal.cpp
index 3059496f..5787d8ec 100644
--- a/DSView/pv/view/analogsignal.cpp
+++ b/DSView/pv/view/analogsignal.cpp
@@ -195,7 +195,7 @@ bool AnalogSignal::measure(const QPointF &p)
     if (!enabled())
         return false;
 
-    if (_view->session().get_capture_state() != SigSession::Stopped)
+    if (_view->session().is_stopped_status() == false)
         return false;
 
     const QRectF window = get_view_rect();
@@ -404,7 +404,7 @@ int AnalogSignal::get_zero_vpos()
 
 void AnalogSignal::set_zero_ratio(double ratio)
 {
-    if (_view->session().get_capture_state() == SigSession::Running)
+    if (_view->session().is_running_status())
         return;
 
     _zero_offset = ratio2value(ratio);
@@ -557,7 +557,7 @@ void AnalogSignal::paint_fore(QPainter &p, int left, int right, QColor fore, QCo
     fore.setAlpha(View::ForeAlpha);
     if(enabled()) {
         // Paint measure
-        if (_view->session().get_capture_state() == SigSession::Stopped)
+        if (_view->session().is_stopped_status())
             paint_hover_measure(p, fore, back);
     }
 }
diff --git a/DSView/pv/view/decodetrace.cpp b/DSView/pv/view/decodetrace.cpp
index 40ec86b4..0873b5fc 100644
--- a/DSView/pv/view/decodetrace.cpp
+++ b/DSView/pv/view/decodetrace.cpp
@@ -567,7 +567,7 @@ void DecodeTrace::on_new_decode_data()
     }
     decoded_progress(_progress);
 
-    if (_view && _view->session().get_capture_state() == SigSession::Stopped)
+    if (_view && _view->session().is_stopped_status())
         _view->data_updated();
     if (_totalHeight/_view->get_signalHeight() != rows_size())
         _view->signals_changed();
diff --git a/DSView/pv/view/devmode.cpp b/DSView/pv/view/devmode.cpp
index cd28ddb0..c5127bed 100644
--- a/DSView/pv/view/devmode.cpp
+++ b/DSView/pv/view/devmode.cpp
@@ -105,7 +105,7 @@ void DevMode::changeEvent(QEvent *event)
 void DevMode::set_device()
 { 
      if (_device_agent->have_instance() == false){
-        dsv_info("%s", "DevMode::set_device, Have no device.");        
+        dsv_detail("%s", "DevMode::set_device, Have no device.");   
         return;
      }
 
@@ -197,10 +197,8 @@ void DevMode::on_mode_change()
     {
         if ((*i).first == action) {
             if (_device_agent->get_work_mode() != (*i).second->mode) {
-                _session->set_run_mode(SigSession::Single);
-                _session->set_repeating(false);
                 _session->stop_capture();
-                _session->capture_state_changed(SigSession::Stopped);
+                _session->set_repeat_mode(false); 
                 _session->session_save();
                 _device_agent->set_config(NULL, NULL,
                                      SR_CONF_DEVICE_MODE,
diff --git a/DSView/pv/view/dsosignal.cpp b/DSView/pv/view/dsosignal.cpp
index 3c9cdfad..e61da76e 100644
--- a/DSView/pv/view/dsosignal.cpp
+++ b/DSView/pv/view/dsosignal.cpp
@@ -174,11 +174,13 @@ void DsoSignal::set_enable(bool enable)
     }
 
     bool running =  false;
-    if (session->get_capture_state() == SigSession::Running) {
+
+    if (session->is_running_status()) {
         running = true;
         session->stop_capture();
     }
-    while(session->get_capture_state() == SigSession::Running)
+
+    while(session->is_running_status())
         QCoreApplication::processEvents();
 
     set_vDialActive(false);
@@ -211,14 +213,18 @@ bool DsoSignal::go_vDialPre(bool manul)
     if (_autoV && manul)
         autoV_end(); 
 
-    if (enabled() && !_vDial->isMin()) {
-        if (session->get_capture_state() == SigSession::Running)
+    if (enabled() && !_vDial->isMin()) 
+    {
+        if (session->is_running_status())
             session->refresh(RefreshShort);
+
         const double pre_vdiv = _vDial->get_value();
         _vDial->set_sel(_vDial->get_sel() - 1);
+
         session->get_device()->set_config(_probe, NULL, SR_CONF_PROBE_VDIV,
                               g_variant_new_uint64(_vDial->get_value()));
-        if (session->get_capture_state() == SigSession::Stopped) {
+
+        if (session->is_stopped_status()) {
             session->set_stop_scale(session->stop_scale() * (pre_vdiv/_vDial->get_value()));
             set_scale(get_view_rect().height());
         }
@@ -229,7 +235,8 @@ bool DsoSignal::go_vDialPre(bool manul)
         _view->set_update(_viewport, true);
         _view->update();
         return true;
-    } else {
+    }
+    else {
         if (_autoV && !_autoV_over)
             autoV_end();
         return false;
@@ -241,14 +248,18 @@ bool DsoSignal::go_vDialNext(bool manul)
     if (_autoV && manul)
         autoV_end(); 
 
-    if (enabled() && !_vDial->isMax()) {
-        if (session->get_capture_state() == SigSession::Running)
+    if (enabled() && !_vDial->isMax())
+    {
+        if (session->is_running_status())
             session->refresh(RefreshShort);
+
         const double pre_vdiv = _vDial->get_value();
         _vDial->set_sel(_vDial->get_sel() + 1);
+
         session->get_device()->set_config(_probe, NULL, SR_CONF_PROBE_VDIV,
                               g_variant_new_uint64(_vDial->get_value()));
-        if (session->get_capture_state() == SigSession::Stopped) {
+
+        if (session->is_stopped_status()) {
             session->set_stop_scale(session->stop_scale() * (pre_vdiv/_vDial->get_value()));
             set_scale(get_view_rect().height());
         }
@@ -259,7 +270,8 @@ bool DsoSignal::go_vDialNext(bool manul)
         _view->set_update(_viewport, true);
         _view->update();
         return true;
-    } else {
+    } 
+    else {
         if (_autoV && !_autoV_over)
             autoV_end();
         return false;
@@ -1011,7 +1023,7 @@ void DsoSignal::paint_fore(QPainter &p, int left, int right, QColor fore, QColor
         p.drawText(label_rect, Qt::AlignCenter | Qt::AlignVCenter, "T");
 
         // Paint measure
-        if (session->get_capture_state() == SigSession::Stopped)
+        if (session->is_stopped_status())
             paint_hover_measure(p, fore, back);
 
         // autoset
@@ -1370,12 +1382,13 @@ void DsoSignal::paint_hover_measure(QPainter &p, QColor fore, QColor back)
 
 void DsoSignal::auto_set()
 { 
-    if (session->get_capture_state() == SigSession::Stopped) {
+    if (session->is_stopped_status()) {
         if (_autoV)
             autoV_end();
         if (_autoH)
             autoH_end();
-    } else {
+    } 
+    else {
         if (_autoH && _autoV && get_zero_ratio() != 0.5) {
             set_zero_ratio(0.5);
         }
@@ -1462,7 +1475,7 @@ void DsoSignal::auto_start()
     if (_autoV || _autoH)
         return;
 
-    if (session->get_capture_state() == SigSession::Running) {
+    if (session->is_running_status()) {
         session->data_auto_lock(AutoLock);
         _autoV = true;
         _autoH = true;
@@ -1474,10 +1487,11 @@ void DsoSignal::auto_start()
 bool DsoSignal::measure(const QPointF &p)
 { 
     _hover_en = false;
+    
     if (!enabled() || !show())
         return false;
 
-    if (session->get_capture_state() != SigSession::Stopped)
+    if (session->is_stopped_status() == false)
         return false;
 
     const QRectF window = get_view_rect();
diff --git a/DSView/pv/view/header.cpp b/DSView/pv/view/header.cpp
index b4e834c2..185fb0e4 100644
--- a/DSView/pv/view/header.cpp
+++ b/DSView/pv/view/header.cpp
@@ -168,8 +168,9 @@ void Header::mousePressEvent(QMouseEvent *event)
 
     const auto &traces = _view.get_traces(ALL_VIEW);
     int action;
-    const bool instant = _view.session().get_instant();
-    if (instant && _view.session().get_capture_state() == SigSession::Running) {
+
+    const bool instant = _view.session().is_instant();
+    if (instant && _view.session().is_running_status()) {
         return;
     }
 
diff --git a/DSView/pv/view/mathtrace.cpp b/DSView/pv/view/mathtrace.cpp
index 8b2075c1..b36c6177 100644
--- a/DSView/pv/view/mathtrace.cpp
+++ b/DSView/pv/view/mathtrace.cpp
@@ -104,12 +104,12 @@ void MathTrace::update_vDial()
 void MathTrace::go_vDialPre()
 {
     if (enabled() && !_vDial->isMin()) {
-        if (_view->session().get_capture_state() == SigSession::Running)
+        if (_view->session().is_running_status())
             _view->session().refresh(DsoSignal::RefreshShort);
         const double pre_vdiv = _vDial->get_value();
         _vDial->set_sel(_vDial->get_sel() - 1);
 
-        if (_view->session().get_capture_state() == SigSession::Stopped)
+        if (_view->session().is_stopped_status())
             _scale *= pre_vdiv/_vDial->get_value();
 
         _view->set_update(_viewport, true);
@@ -120,12 +120,12 @@ void MathTrace::go_vDialPre()
 void MathTrace::go_vDialNext()
 {
     if (enabled() && !_vDial->isMax()) {
-        if (_view->session().get_capture_state() == SigSession::Running)
+        if (_view->session().is_running_status())
             _view->session().refresh(DsoSignal::RefreshShort);
         const double pre_vdiv = _vDial->get_value();
         _vDial->set_sel(_vDial->get_sel() + 1);
 
-        if (_view->session().get_capture_state() == SigSession::Stopped)
+        if (_view->session().is_stopped_status())
             _scale *= pre_vdiv/_vDial->get_value();
 
         _view->set_update(_viewport, true);
@@ -255,7 +255,7 @@ void MathTrace::paint_fore(QPainter &p, int left, int right, QColor fore, QColor
 
     // Paint measure
     fore.setAlpha(View::ForeAlpha);
-    if (_view->session().get_capture_state() == SigSession::Stopped)
+    if (_view->session().is_stopped_status())
         paint_hover_measure(p, fore, back);
 }
 
diff --git a/DSView/pv/view/ruler.cpp b/DSView/pv/view/ruler.cpp
index 693c1c6e..541bdf37 100644
--- a/DSView/pv/view/ruler.cpp
+++ b/DSView/pv/view/ruler.cpp
@@ -460,7 +460,7 @@ void Ruler::draw_logic_tick_mark(QPainter &p)
         auto i = _view.get_cursorList().begin();
         int index = 1;
         while (i != _view.get_cursorList().end()) {
-            (*i)->paint_label(p, rect(), prefix, index, _view.session().get_capture_state() == SigSession::Stopped);
+            (*i)->paint_label(p, rect(), prefix, index, _view.session().is_stopped_status());
             index++;
             i++;
         }
@@ -578,7 +578,7 @@ void Ruler::draw_osc_tick_mark(QPainter &p)
         auto i = _view.get_cursorList().begin();
         int index = 1;
         while (i != _view.get_cursorList().end()) {
-            (*i)->paint_label(p, rect(), prefix, index, _view.session().get_capture_state() == SigSession::Stopped);
+            (*i)->paint_label(p, rect(), prefix, index, _view.session().is_stopped_status());
             index++;
             i++;
         }
diff --git a/DSView/pv/view/view.cpp b/DSView/pv/view/view.cpp
index 74cd3263..ef865568 100644
--- a/DSView/pv/view/view.cpp
+++ b/DSView/pv/view/view.cpp
@@ -102,7 +102,6 @@ View::View(SigSession *session, pv::toolbars::SamplingBar *sampling_bar, QWidget
 
    _session = session;
    _device_agent = session->get_device();
-   session->add_msg_listener(this);
 
     setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOn);
   
@@ -249,7 +248,7 @@ void View::capture_init()
 
     if (mode == DSO)
         show_trig_cursor(true);
-    else if (!_session->isRepeating())
+    else if (!_session->is_repeating())
         show_trig_cursor(false);
 
     _maxscale = _session->cur_sampletime() / (get_view_width() * MaxViewRate);
@@ -297,10 +296,11 @@ bool View::zoom(double steps, int offset)
     if (_device_agent->get_work_mode() != DSO) {
         _scale *= std::pow(3.0/2.0, -steps);
         _scale = max(min(_scale, _maxscale), _minscale);
-    } else {
-        if (_session->get_capture_state() == SigSession::Running &&
-            _session->get_instant())
+    } 
+    else {
+        if (_session->is_running_status() && _session->is_instant()){
             return ret;
+        }
 
         double hori_res = -1;
         if(steps > 0.5)
@@ -343,20 +343,18 @@ void View::timebase_changed()
 
 void View::set_scale_offset(double scale, int64_t offset)
 {
-    //if (_session->get_capture_state() == SigSession::Stopped) {
-        _preScale = _scale;
-        _preOffset = _offset;
+    _preScale = _scale;
+    _preOffset = _offset;
 
-        _scale = max(min(scale, _maxscale), _minscale);
-        _offset = floor(max(min(offset, get_max_offset()), get_min_offset()));
+    _scale = max(min(scale, _maxscale), _minscale);
+    _offset = floor(max(min(offset, get_max_offset()), get_min_offset()));
 
-        if (_scale != _preScale || _offset != _preOffset) {
-            update_scroll();
-            _header->update();
-            _ruler->update();
-            viewport_update();
-        }
-    //}
+    if (_scale != _preScale || _offset != _preOffset) {
+        update_scroll();
+        _header->update();
+        _ruler->update();
+        viewport_update();
+    }
 }
 
 void View::set_preScale_preOffset()
@@ -1371,27 +1369,5 @@ void View::check_calibration()
         }
 }
 
-void View::OnMessage(int msg)
-{ 
-    switch (msg)
-    {
-    case DSV_MSG_DEVICE_OPTIONS_UPDATED:
-        check_calibration();
-        break;
-    case DSV_MSG_COLLECT_START_PREV:
-        capture_init();
-        break;
-    case DSV_MSG_DEVICE_DURATION_UPDATED:
-        timebase_changed();
-        break; 
-    case DSV_MSG_DEVICE_MODE_CHANGED:
-        mode_changed();
-        break;
-    case DSV_MSG_CURRENT_DEVICE_CHANGED:
-        reload();
-        break;
-    }
-}
-
 } // namespace view
 } // namespace pv
diff --git a/DSView/pv/view/view.h b/DSView/pv/view/view.h
index a82cb117..ead5d8ca 100644
--- a/DSView/pv/view/view.h
+++ b/DSView/pv/view/view.h
@@ -41,8 +41,7 @@
 #include "xcursor.h"
 #include "signal.h"
 #include "viewstatus.h"
-#include "../dsvdef.h"
-#include "../interface/icallbacks.h"
+#include "../dsvdef.h" 
 
 class DeviceAgent;
 
@@ -69,7 +68,7 @@ class Viewport;
 class LissajousFigure;
 
 //created by MainWindow
-class View : public QScrollArea, public IMessageListener {
+class View : public QScrollArea {
 	Q_OBJECT
 
 private:
@@ -247,22 +246,18 @@ public:
 
     int get_cursor_index_by_key(uint64_t key);
 
+    void check_calibration();
+
 signals:
 	void hover_point_changed();
-
     void cursor_update();
     void xcursor_update();
-
     void cursor_moving();
     void cursor_moved();
-
     void measure_updated();
-
     void prgRate(int progress);
-
     void resize();
-
-    void auto_trig(int index);
+    void auto_trig(int index);   
 
 private: 
     void get_scroll_layout(int64_t &length, int64_t &offset);
@@ -276,20 +271,11 @@ private:
         const pv::view::Trace *b);
 
     void clear();
-    void reconstruct();
-
-    //IMessageListener 
-    void OnMessage(int msg);
-
-private:
+    void reconstruct();  
 	bool eventFilter(QObject *object, QEvent *event);
-
 	bool viewportEvent(QEvent *e);
-
 	void resizeEvent(QResizeEvent *e);
-
-    void check_calibration();
-
+ 
 public slots:
     void reload();
     void set_measure_en(int enable);
@@ -324,6 +310,8 @@ public slots:
 
     void frame_began();
 
+    void mode_changed();
+
 private slots:
 
 	void h_scroll_value_changed(int value);
@@ -344,8 +332,6 @@ private slots:
 
     void splitterMoved(int pos, int index);
 
-    void mode_changed();
-
 public:
     void show_wait_trigger();
     void set_device();
diff --git a/DSView/pv/view/viewport.cpp b/DSView/pv/view/viewport.cpp
index ac57e3a8..a753c5ed 100644
--- a/DSView/pv/view/viewport.cpp
+++ b/DSView/pv/view/viewport.cpp
@@ -160,32 +160,26 @@ void Viewport::paintEvent(QPaintEvent *event)
         t->paint_back(p, 0, _view.get_view_width(), fore, back);
         if (_view.back_ready())
             break;
-    }
-
-    //auto st = _view.session().get_capture_state();
+    } 
 
     if (_view.session().get_device()->get_work_mode() == LOGIC ||
-        _view.session().get_instant()) {
-        switch(_view.session().get_capture_state()) {
-        case SigSession::Init:
-            break;
-
-        case SigSession::Stopped:
+        _view.session().is_instant()) 
+    {
+        if (_view.session().is_stopped_status()){
             paintSignals(p, fore, back);
-            break;
-
-        case SigSession::Running:
-            if (_view.session().isRepeating() &&
-                !transfer_started) {
+        }
+        else if (_view.session().is_running_status()){
+            if (_view.session().is_repeat_mode() && !transfer_started) {
                 _view.set_capture_status();
                 paintSignals(p, fore, back);
-            } else if (_type == TIME_VIEW) {
+            }
+            else if (_type == TIME_VIEW) {
                 _view.repeat_unshow();
                 paintProgress(p, fore, back);
             }
-            break;
-        }
-    } else {
+        }     
+    }
+    else {
         paintSignals(p, fore, back);
     }
 
@@ -259,9 +253,9 @@ void Viewport::paintSignals(QPainter &p, QColor fore, QColor back)
             const int64_t cursorX = _view.index2pixel((*i)->index());
             if (xrect.contains(_view.hover_point().x(), _view.hover_point().y()) &&
                     qAbs(cursorX - _view.hover_point().x()) <= HitCursorMargin)
-                (*i)->paint(p, xrect, 1, index, _view.session().get_capture_state() == SigSession::Stopped);
+                (*i)->paint(p, xrect, 1, index, _view.session().is_stopped_status());
             else
-                (*i)->paint(p, xrect, 0, index, _view.session().get_capture_state() == SigSession::Stopped);
+                (*i)->paint(p, xrect, 0, index, _view.session().is_stopped_status());
             i++;
             index++;
         }
@@ -328,8 +322,9 @@ void Viewport::paintSignals(QPainter &p, QColor fore, QColor back)
         paintMeasure(p, fore, back);
 
         //plot trigger information
-        if (_view.session().get_device()->get_work_mode() == DSO &&
-            _view.session().get_capture_state() == SigSession::Running) {
+        if (_view.session().get_device()->get_work_mode() == DSO
+            && _view.session().is_running_status()) 
+        {
             uint8_t type;
             bool roll = false;
             QString type_str="";
@@ -506,12 +501,14 @@ void Viewport::mousePressEvent(QMouseEvent *event)
     _drag_strength = 0;
     _elapsed_time.restart();
 
-    if (_action_type == NO_ACTION &&
-        event->button() == Qt::RightButton &&
-        _view.session().get_capture_state() == SigSession::Stopped) {
+    if (_action_type == NO_ACTION
+        && event->button() == Qt::RightButton
+        && _view.session().is_stopped_status())
+    {
         if (_view.session().get_device()->get_work_mode() == LOGIC) {
             _action_type = LOGIC_ZOOM;
-        } else if (_view.session().get_device()->get_work_mode() == DSO) {
+        }
+        else if (_view.session().get_device()->get_work_mode() == DSO) {
             if (_hover_hit) {
                 const int64_t index = _view.pixel2index(event->pos().x());
                 _view.add_cursor(view::Ruler::CursorColor[_view.get_cursorList().size() % 8], index);
@@ -768,10 +765,10 @@ void Viewport::mouseReleaseEvent(QMouseEvent *event)
         return;
     }
   
-        if ((_action_type == NO_ACTION) &&
-            (event->button() == Qt::LeftButton)) {
-            if (_view.session().get_device()->get_work_mode() == LOGIC &&
-                _view.session().get_capture_state() == SigSession::Stopped) {
+        if ((_action_type == NO_ACTION) && (event->button() == Qt::LeftButton)) 
+        {
+            if (_view.session().get_device()->get_work_mode() == LOGIC
+                && _view.session().is_stopped_status()) {
                 //priority 1
                 //try to quick scroll view...
                 int curX = event->globalPos().x();
@@ -976,14 +973,16 @@ void Viewport::mouseDoubleClickEvent(QMouseEvent *event)
     if (!_view.get_view_rect().contains(event->pos()))
         return;
 
-    if (_view.session().get_device()->get_work_mode() == LOGIC &&
-        _view.session().get_capture_state() == SigSession::Stopped) {
+    if (_view.session().get_device()->get_work_mode() == LOGIC
+        && _view.session().is_stopped_status()) 
+    {
         if (event->button() == Qt::RightButton) {
             if (_view.scale() == _view.get_maxscale())
                 _view.set_preScale_preOffset();
             else
                 _view.set_scale_offset(_view.get_maxscale(), _view.get_min_offset());
-        } else if (event->button() == Qt::LeftButton) {
+        }
+        else if (event->button() == Qt::LeftButton) {
             bool logic = false;
             uint64_t index;
             uint64_t index0 = 0, index1 = 0, index2 = 0;
@@ -1015,13 +1014,15 @@ void Viewport::mouseDoubleClickEvent(QMouseEvent *event)
             _view.show_cursors(true);
         }
         update();
-    } else if (_view.session().get_device()->get_work_mode() == DSO &&
-               _view.session().get_capture_state() != SigSession::Init &&
-               event->button() == Qt::LeftButton) {
+    }
+    else if (_view.session().get_device()->get_work_mode() == DSO
+             && _view.session().is_init_status() == false
+             && event->button() == Qt::LeftButton) {
         if (_dso_xm_valid) {
             clear_dso_xm();
             measure_updated();
-        } else if (_action_type == NO_ACTION) {
+        }
+        else if (_action_type == NO_ACTION) {
             for(auto &s : _view.session().get_signals()) {
                 assert(s);
                 if (s->get_view_rect().contains(event->pos())) {
@@ -1691,20 +1692,24 @@ void Viewport::on_drag_timer()
 {   
     const int64_t offset = _view.offset();
     const double scale = _view.scale();
-    if (_view.session().get_capture_state() == SigSession::Stopped &&
-        _drag_strength != 0 &&
-        offset < _view.get_max_offset() &&
-        offset > _view.get_min_offset()) {
+
+    if (_view.session().is_stopped_status()
+        && _drag_strength != 0
+        && offset < _view.get_max_offset()
+        && offset > _view.get_min_offset()) 
+    {
         _view.set_scale_offset(scale, offset + _drag_strength);
         _drag_strength /= DragDamping;
         if (_drag_strength != 0)
             _drag_timer.start(DragTimerInterval);
-    } else if (offset == _view.get_max_offset() ||
-               offset == _view.get_min_offset()) {
+    }
+    else if (offset == _view.get_max_offset() ||
+             offset == _view.get_min_offset()) {
         _drag_strength = 0;
         _drag_timer.stop();
         _action_type = NO_ACTION;
-    }else if (_action_type == NO_ACTION){
+    }
+    else if (_action_type == NO_ACTION){
         _drag_strength = 0;
         _drag_timer.stop();
     }
diff --git a/libsigrok4DSL/lib_main.c b/libsigrok4DSL/lib_main.c
index 1acbc82f..f2f68a69 100644
--- a/libsigrok4DSL/lib_main.c
+++ b/libsigrok4DSL/lib_main.c
@@ -34,7 +34,7 @@
 #endif
 
 #undef LOG_PREFIX
-#define LOG_PREFIX "lib_main: " 
+#define LOG_PREFIX "lib_main: "
 
 char DS_RES_PATH[500] = {0};
 
@@ -58,6 +58,7 @@ struct sr_lib_context
 	ds_datafeed_callback_t data_forward_callback;
 	int callback_thread_count;
 	int is_delay_destory_actived_device;
+	int is_stop_by_detached;
 };
 
 static void hotplug_event_listen_callback(struct libusb_context *ctx, struct libusb_device *dev, int event);
@@ -88,6 +89,7 @@ static struct sr_lib_context lib_ctx = {
 	.collect_thread = NULL,
 	.callback_thread_count = 0,
 	.is_delay_destory_actived_device = 0,
+	.is_stop_by_detached = 0,
 };
 
 /**
@@ -158,7 +160,9 @@ SR_API int ds_lib_exit()
 	sr_info("Uninit %s.", SR_LIB_NAME);
 
 	if (ds_is_collecting())
+	{
 		ds_stop_collect(); // stop collect.
+	}
 
 	sr_close_hotplug(lib_ctx.sr_ctx);
 
@@ -171,8 +175,7 @@ SR_API int ds_lib_exit()
 	}
 
 	// The device is not in list.
-	if (lib_ctx.is_delay_destory_actived_device 
-			&& lib_ctx.actived_device_instance != NULL)
+	if (lib_ctx.is_delay_destory_actived_device && lib_ctx.actived_device_instance != NULL)
 	{
 		sr_info("The current device is delayed for destruction, handle:%p", lib_ctx.actived_device_instance->handle);
 		destroy_device_instance(lib_ctx.actived_device_instance);
@@ -284,10 +287,11 @@ SR_API int ds_get_device_list(struct ds_device_info **out_list, int *out_count)
 		p->di = dev;
 		strncpy(p->name, dev->name, sizeof(p->name) - 1);
 
-		if (dev->driver && dev->driver->name){
+		if (dev->driver && dev->driver->name)
+		{
 			strncpy(p->driver_name, dev->driver->name, sizeof(p->driver_name) - 1);
 		}
-		
+
 		p++;
 	}
 
@@ -333,16 +337,18 @@ SR_API int ds_active_device(ds_device_handle handle)
 
 	if (lib_ctx.actived_device_instance != NULL)
 	{
-		if (lib_ctx.is_delay_destory_actived_device){
+		if (lib_ctx.is_delay_destory_actived_device)
+		{
 			sr_info("The current device is delayed for destruction, handle:%p", lib_ctx.actived_device_instance->handle);
 			destroy_device_instance(lib_ctx.actived_device_instance);
 			lib_ctx.actived_device_instance = NULL;
 			lib_ctx.is_delay_destory_actived_device = 0;
 		}
-		else{
+		else
+		{
 			sr_info("Close the previous device \"%s\"", lib_ctx.actived_device_instance->name);
-		    close_device_instance(lib_ctx.actived_device_instance);
-		}		
+			close_device_instance(lib_ctx.actived_device_instance);
+		}
 	}
 
 	// To open the new.
@@ -353,13 +359,15 @@ SR_API int ds_active_device(ds_device_handle handle)
 		{
 			bFind = 1;
 
-			if (dev->dev_type == DEV_TYPE_USB && DS_RES_PATH[0] == '\0'){
+			if (dev->dev_type == DEV_TYPE_USB && DS_RES_PATH[0] == '\0')
+			{
 				sr_err("%s", "Please call ds_set_firmware_resource_dir() to set the firmware resource path.");
 			}
 
 			sr_info("Switch \"%s\" to current device.", dev->name);
 
-			if (open_device_instance(dev) == SR_OK){
+			if (open_device_instance(dev) == SR_OK)
+			{
 				lib_ctx.actived_device_instance = dev;
 			}
 			else
@@ -462,7 +470,8 @@ SR_API int ds_get_actived_device_index()
  */
 SR_API int ds_have_actived_device()
 {
-	if (lib_ctx.actived_device_instance != NULL){
+	if (lib_ctx.actived_device_instance != NULL)
+	{
 		return 1;
 	}
 	return 0;
@@ -483,19 +492,21 @@ SR_API int ds_device_from_file(const char *file_path)
 SR_API const GSList *ds_get_actived_device_mode_list()
 {
 	GSList *l;
-	struct sr_dev_inst *dev; 
+	struct sr_dev_inst *dev;
 
-	dev = lib_ctx.actived_device_instance ;
+	dev = lib_ctx.actived_device_instance;
 
-	if (dev == NULL){
+	if (dev == NULL)
+	{
 		sr_err("%s", "Have no actived device.");
 	}
-	if (dev->driver == NULL || dev->driver->dev_mode_list == NULL){
+	if (dev->driver == NULL || dev->driver->dev_mode_list == NULL)
+	{
 		sr_err("%s", "Module not implemented.");
 		return NULL;
 	}
 
-	 return dev->driver->dev_mode_list(dev);
+	return dev->driver->dev_mode_list(dev);
 }
 
 /**
@@ -506,22 +517,18 @@ SR_API int ds_remove_device(ds_device_handle handle)
 {
 	GSList *l;
 	struct sr_dev_inst *dev;
-	int bFind = 0; 
+	int bFind = 0;
 
 	if (handle == NULL_HANDLE)
 		return SR_ERR_ARG;
 
-	if (lib_ctx.actived_device_instance != NULL
-		 && lib_ctx.actived_device_instance->handle == handle
-		 && ds_is_collecting())
+	if (lib_ctx.actived_device_instance != NULL && lib_ctx.actived_device_instance->handle == handle && ds_is_collecting())
 	{
 		sr_err("%s", "Device is collecting, can't remove it.");
 		return SR_ERR_CALL_STATUS;
 	}
 
-	if (lib_ctx.actived_device_instance != NULL 
-		&& lib_ctx.is_delay_destory_actived_device
-		&& lib_ctx.actived_device_instance->handle == handle)
+	if (lib_ctx.actived_device_instance != NULL && lib_ctx.is_delay_destory_actived_device && lib_ctx.actived_device_instance->handle == handle)
 	{
 		sr_info("The current device is delayed for destruction, handle:%p", lib_ctx.actived_device_instance->handle);
 		destroy_device_instance(lib_ctx.actived_device_instance);
@@ -538,7 +545,8 @@ SR_API int ds_remove_device(ds_device_handle handle)
 		{
 			lib_ctx.device_list = g_slist_remove(lib_ctx.device_list, l->data);
 
-			if (dev == lib_ctx.actived_device_instance){
+			if (dev == lib_ctx.actived_device_instance)
+			{
 				lib_ctx.actived_device_instance = NULL;
 			}
 
@@ -564,7 +572,7 @@ SR_API int ds_get_actived_device_info(struct ds_device_info *fill_info)
 	struct sr_dev_inst *dev;
 	struct ds_device_info *p;
 	int ret;
-	
+
 	if (fill_info == NULL)
 		return SR_ERR_ARG;
 
@@ -588,9 +596,10 @@ SR_API int ds_get_actived_device_info(struct ds_device_info *fill_info)
 		p->di = dev;
 		strncpy(p->name, dev->name, sizeof(p->name) - 1);
 
-		if (dev->driver && dev->driver->name){
+		if (dev->driver && dev->driver->name)
+		{
 			strncpy(p->driver_name, dev->driver->name, sizeof(p->driver_name) - 1);
-		}		
+		}
 		ret = SR_OK;
 	}
 
@@ -674,6 +683,9 @@ static void collect_run_proc()
 {
 	int ret;
 	struct sr_dev_inst *di;
+	int bError;
+	
+	bError = 0;
 	di = lib_ctx.actived_device_instance;
 
 	send_event(DS_EV_COLLECT_TASK_START);
@@ -683,6 +695,7 @@ static void collect_run_proc()
 	if (di == NULL || di->driver == NULL || di->driver->dev_acquisition_start == NULL)
 	{
 		sr_err("%s", "The device cannot be used.");
+		bError = 1;
 		goto END;
 	}
 
@@ -692,20 +705,35 @@ static void collect_run_proc()
 		sr_err("Failed to start acquisition of device in "
 			   "running session: %d",
 			   ret);
+		bError = 1;
 		goto END;
 	}
 
+	send_event(DS_EV_DEVICE_RUNNING);
+
 	ret = sr_session_run();
-	if (ret != SR_OK){
+
+	send_event(DS_EV_DEVICE_STOPPED);
+
+	if (ret != SR_OK)
+	{
 		sr_err("%s", "Run session error!");
+		bError = 1;
 		goto END;
-	} 
+	}
 
 END:
 	sr_info("%s", "Collect thread end.");
 	lib_ctx.collect_thread = NULL;
 
-	send_event(DS_EV_COLLECT_TASK_END);	
+	if (bError)
+		send_event(DS_EV_COLLECT_TASK_END_BY_ERROR);
+	else if (lib_ctx.is_stop_by_detached)
+		send_event(DS_EV_COLLECT_TASK_END_BY_DETACHED);
+	else
+		send_event(DS_EV_COLLECT_TASK_END); // Normal end.
+
+	lib_ctx.is_stop_by_detached = 0;
 }
 
 /**
@@ -756,7 +784,8 @@ int ds_trigger_is_enabled()
 		for (l = lib_ctx.actived_device_instance->channels; l; l = l->next)
 		{
 			p = (struct sr_channel *)l->data;
-			if (p->trigger && p->trigger[0] != '\0'){
+			if (p->trigger && p->trigger[0] != '\0')
+			{
 				ret = 1;
 				break;
 			}
@@ -767,61 +796,70 @@ int ds_trigger_is_enabled()
 	return ret;
 }
 
+SR_API int ds_trigger_reset()
+{
+	return ds_trigger_init();
+}
+
 /**-------------------public end ---------------*/
 
 /**-------------------config -------------------*/
 SR_API int ds_get_actived_device_config(const struct sr_channel *ch,
-                         const struct sr_channel_group *cg,
-                         int key, GVariant **data)
+										const struct sr_channel_group *cg,
+										int key, GVariant **data)
 {
-	if (lib_ctx.actived_device_instance == NULL){
+	if (lib_ctx.actived_device_instance == NULL)
+	{
 		sr_err("%s", "Have no actived device.");
 		return SR_ERR_CALL_STATUS;
 	}
- 
-	return sr_config_get(lib_ctx.actived_device_instance->driver, 
-				lib_ctx.actived_device_instance, 
-				ch, 
-				cg, 
-				key, 
-				data);
+
+	return sr_config_get(lib_ctx.actived_device_instance->driver,
+						 lib_ctx.actived_device_instance,
+						 ch,
+						 cg,
+						 key,
+						 data);
 }
 
 SR_API int ds_set_actived_device_config(const struct sr_channel *ch,
-                         const struct sr_channel_group *cg,
-                         int key, GVariant *data)
+										const struct sr_channel_group *cg,
+										int key, GVariant *data)
 {
-	if (lib_ctx.actived_device_instance == NULL){
+	if (lib_ctx.actived_device_instance == NULL)
+	{
 		sr_err("%s", "Have no actived device.");
 		return SR_ERR_CALL_STATUS;
 	}
-	
+
 	return sr_config_set(
-				lib_ctx.actived_device_instance, 
-				ch, 
-				cg, 
-				key, 
-				data);
+		lib_ctx.actived_device_instance,
+		ch,
+		cg,
+		key,
+		data);
 }
 
 SR_API int ds_get_actived_device_config_list(const struct sr_channel_group *cg,
-                          int key, GVariant **data)
+											 int key, GVariant **data)
 {
-	if (lib_ctx.actived_device_instance == NULL){
+	if (lib_ctx.actived_device_instance == NULL)
+	{
 		sr_err("%s", "Have no actived device.");
 		return SR_ERR_CALL_STATUS;
 	}
 
 	return sr_config_list(lib_ctx.actived_device_instance->driver,
-				lib_ctx.actived_device_instance,
-				cg, 
-				key, 
-				data);
+						  lib_ctx.actived_device_instance,
+						  cg,
+						  key,
+						  data);
 }
 
-SR_API const struct sr_config_info* ds_get_actived_device_config_info(int key)
+SR_API const struct sr_config_info *ds_get_actived_device_config_info(int key)
 {
-	if (lib_ctx.actived_device_instance == NULL){
+	if (lib_ctx.actived_device_instance == NULL)
+	{
 		sr_err("%s", "Have no actived device.");
 		return SR_ERR_CALL_STATUS;
 	}
@@ -829,9 +867,10 @@ SR_API const struct sr_config_info* ds_get_actived_device_config_info(int key)
 	return sr_config_info_get(key);
 }
 
-SR_API const struct sr_config_info* ds_get_actived_device_config_info_by_name(const char *optname)
+SR_API const struct sr_config_info *ds_get_actived_device_config_info_by_name(const char *optname)
 {
-	if (lib_ctx.actived_device_instance == NULL){
+	if (lib_ctx.actived_device_instance == NULL)
+	{
 		sr_err("%s", "Have no actived device.");
 		return SR_ERR_CALL_STATUS;
 	}
@@ -840,7 +879,8 @@ SR_API const struct sr_config_info* ds_get_actived_device_config_info_by_name(co
 
 SR_API int ds_get_actived_device_status(struct sr_status *status, gboolean prg)
 {
-	if (lib_ctx.actived_device_instance == NULL){
+	if (lib_ctx.actived_device_instance == NULL)
+	{
 		sr_err("%s", "Have no actived device.");
 		return SR_ERR_CALL_STATUS;
 	}
@@ -861,7 +901,8 @@ SR_API void ds_free_config(struct sr_config *src)
 /**-----------channel -------------*/
 SR_API int ds_enable_device_channel(const struct sr_channel *ch, gboolean enable)
 {
-	if (lib_ctx.actived_device_instance == NULL){
+	if (lib_ctx.actived_device_instance == NULL)
+	{
 		return SR_ERR_CALL_STATUS;
 	}
 	return sr_enable_device_channel(lib_ctx.actived_device_instance, ch, enable);
@@ -869,7 +910,8 @@ SR_API int ds_enable_device_channel(const struct sr_channel *ch, gboolean enable
 
 SR_API int ds_enable_device_channel_index(int ch_index, gboolean enable)
 {
-	if (lib_ctx.actived_device_instance == NULL){
+	if (lib_ctx.actived_device_instance == NULL)
+	{
 		return SR_ERR_CALL_STATUS;
 	}
 	return sr_dev_probe_enable(lib_ctx.actived_device_instance, ch_index, enable);
@@ -877,10 +919,11 @@ SR_API int ds_enable_device_channel_index(int ch_index, gboolean enable)
 
 SR_API int ds_set_device_channel_name(int ch_index, const char *name)
 {
-	if (lib_ctx.actived_device_instance == NULL){
+	if (lib_ctx.actived_device_instance == NULL)
+	{
 		return SR_ERR_CALL_STATUS;
 	}
-	return sr_dev_probe_name_set(lib_ctx.actived_device_instance, ch_index,  name);
+	return sr_dev_probe_name_set(lib_ctx.actived_device_instance, ch_index, name);
 }
 
 /**
@@ -900,7 +943,8 @@ int ds_channel_is_enabled()
 		for (l = lib_ctx.actived_device_instance->channels; l; l = l->next)
 		{
 			p = (struct sr_channel *)l->data;
-			if (p->enabled){
+			if (p->enabled)
+			{
 				ret = 1;
 				break;
 			}
@@ -910,9 +954,10 @@ int ds_channel_is_enabled()
 	return ret;
 }
 
-GSList* ds_get_actived_device_channels()
+GSList *ds_get_actived_device_channels()
 {
-	if (lib_ctx.actived_device_instance != NULL){
+	if (lib_ctx.actived_device_instance != NULL)
+	{
 		return lib_ctx.actived_device_instance->channels;
 	}
 	return NULL;
@@ -1114,6 +1159,13 @@ static void hotplug_event_listen_callback(struct libusb_context *ctx, struct lib
 				   lib_ctx.detach_device_handle);
 		}
 
+		if (lib_ctx.actived_device_instance != NULL && lib_ctx.actived_device_instance->handle == (ds_device_handle)dev && ds_is_collecting())
+		{
+			sr_info("%s", "The actived device is detached, will stop collect thread.");
+			lib_ctx.is_stop_by_detached = 1;
+			ds_stop_collect();
+		}
+
 		/**
 		 * Begin to wait the device reconnect, if timeout, will process the detach event.
 		 */
@@ -1131,7 +1183,7 @@ static void process_attach_event()
 {
 	struct sr_dev_driver **drivers;
 	GList *dev_list;
-	GSList *l; 
+	GSList *l;
 	struct sr_dev_driver *dr;
 	int num = 0;
 
@@ -1158,7 +1210,8 @@ static void process_attach_event()
 
 				pthread_mutex_lock(&lib_ctx.mutext);
 
-				for (l = dev_list; l; l = l->next){
+				for (l = dev_list; l; l = l->next)
+				{
 					lib_ctx.device_list = g_slist_append(lib_ctx.device_list, l->data);
 					num++;
 				}
@@ -1181,7 +1234,7 @@ static void process_attach_event()
 }
 
 static void process_detach_event()
-{  
+{
 	GSList *l;
 	struct sr_dev_inst *dev;
 	struct sr_dev_driver *driver_ins;
@@ -1208,27 +1261,24 @@ static void process_detach_event()
 
 		if (dev->handle == (ds_device_handle)ev_dev)
 		{
-			if (dev == lib_ctx.actived_device_instance && ds_is_collecting()){
-				sr_info("%s", "The actived device is detached, will stop collect thread.");
-				ds_stop_collect();
-			}
-
 			// Found the device, and remove it from list.
-			lib_ctx.device_list = g_slist_remove(lib_ctx.device_list, l->data);			
+			lib_ctx.device_list = g_slist_remove(lib_ctx.device_list, l->data);
 
-			if (dev == lib_ctx.actived_device_instance){
+			if (dev == lib_ctx.actived_device_instance)
+			{
 				sr_info("The current device will be delayed for destruction, handle:%p", dev->handle);
 				lib_ctx.is_delay_destory_actived_device = 1;
-				ev = DS_EV_CURRENT_DEVICE_DETACH;			
-			}		
-			else{
+				ev = DS_EV_CURRENT_DEVICE_DETACH;
+			}
+			else
+			{
 				destroy_device_instance(dev);
 			}
-			
+
 			break;
 		}
 	}
-	pthread_mutex_unlock(&lib_ctx.mutext);		
+	pthread_mutex_unlock(&lib_ctx.mutext);
 
 	// Tell user a new device detached, and the list is updated.
 	post_event_async(ev);
@@ -1299,11 +1349,13 @@ static void make_demo_device_to_list()
 		{
 			dev_list = dr->scan(NULL);
 
-			if (dev_list != NULL){ 
+			if (dev_list != NULL)
+			{
 
-				for (l = dev_list; l; l = l->next){
+				for (l = dev_list; l; l = l->next)
+				{
 					lib_ctx.device_list = g_slist_append(lib_ctx.device_list, l->data);
-				} 
+				}
 				g_slist_free(dev_list);
 			}
 		}
@@ -1383,7 +1435,8 @@ static void post_event_async(int event)
 
 static void send_event(int event)
 {
-	if (lib_ctx.event_callback != NULL){
+	if (lib_ctx.event_callback != NULL)
+	{
 		lib_ctx.event_callback(event);
 	}
 }
diff --git a/libsigrok4DSL/libsigrok.h b/libsigrok4DSL/libsigrok.h
index b9733c68..bbde11e4 100644
--- a/libsigrok4DSL/libsigrok.h
+++ b/libsigrok4DSL/libsigrok.h
@@ -1209,6 +1209,7 @@ SR_API const char *sr_error_str(int error_code);
 SR_API const char *sr_error_name(int error_code);
 
 /*--- trigger.c ------------------------------------------------------------*/
+SR_API int ds_trigger_reset();
 SR_API int ds_trigger_stage_set_value(uint16_t stage, uint16_t probes, char *trigger0, char *trigger1);
 SR_API int ds_trigger_stage_set_logic(uint16_t stage, uint16_t probes, unsigned char trigger_logic);
 SR_API int ds_trigger_stage_set_inv(uint16_t stage, uint16_t probes, unsigned char trigger0_inv, unsigned char trigger1_inv);
@@ -1237,21 +1238,38 @@ SR_API void ds_log_level(int level);
 // A new device attached, user need to call ds_get_device_list to get the list,
 // the last one is new.
 // User can call ds_active_device() to switch to the current device.
-#define DS_EV_NEW_DEVICE_ATTACH			0
+//#define DS_EV_NEW_DEVICE_ATTACH         1
 
 // The current device detached, user need to call ds_get_device_list to get the list,
 // and call ds_active_device() to switch to the current device.
-#define DS_EV_CURRENT_DEVICE_DETACH 	1
+//#define DS_EV_CURRENT_DEVICE_DETACH     2
 
 // A inactive device detached.
 // User can call ds_get_device_list() to get the new list, and update the list view.
-#define DS_EV_INACTIVE_DEVICE_DETACH 	2
+//#define DS_EV_INACTIVE_DEVICE_DETACH    3
 
 // The collect task is ends.
-#define DS_EV_COLLECT_TASK_START		100
+#define DS_EV_COLLECT_TASK_START		101
 
 // The collect task is ends.
-#define DS_EV_COLLECT_TASK_END			101
+#define DS_EV_COLLECT_TASK_END			102
+
+// The device is running
+#define DS_EV_DEVICE_RUNNING			103
+
+// The device is stopped
+#define DS_EV_DEVICE_STOPPED			104
+
+#define DS_EV_COLLECT_TASK_END_BY_DETACHED	105
+
+#define DS_EV_COLLECT_TASK_END_BY_ERROR		106
+
+enum bbbb
+{
+		DS_EV_NEW_DEVICE_ATTACH = 1,
+		DS_EV_CURRENT_DEVICE_DETACH = 2,
+		DS_EV_INACTIVE_DEVICE_DETACH = 3,
+};
 
 
 typedef unsigned long long ds_device_handle;