diff --git a/DSView/pv/deviceagent.cpp b/DSView/pv/deviceagent.cpp
index 7fc8ab6c..c4ae2720 100644
--- a/DSView/pv/deviceagent.cpp
+++ b/DSView/pv/deviceagent.cpp
@@ -351,7 +351,7 @@ GSList *DeviceAgent::get_channels()
 
  bool DeviceAgent::get_config_value_int16(int key, int &value)
  {  
-    GVariant* gvar = this->get_config(NULL, NULL, key);
+    GVariant* gvar = get_config(NULL, NULL, key);
     
     if (gvar != NULL) {
         value = g_variant_get_int16(gvar);
@@ -362,8 +362,24 @@ GSList *DeviceAgent::get_channels()
     return false;
  }
 
+ bool DeviceAgent::get_config_value_string(int key, QString &value)
+ {
+    GVariant* gvar = get_config(NULL, NULL, key);
+    
+    if (gvar != NULL) {
+        const gchar *s = g_variant_get_string(gvar, NULL);
+        value = QString(s);
+        g_variant_unref(gvar);
+        return true;
+    }
+
+    return false;
+ }
+
  int DeviceAgent::get_operation_mode()
  {
+    assert(_dev_handle);
+
     int mode_val = 0;
     if (get_config_value_int16(SR_CONF_OPERATION_MODE, mode_val)){                  
         return mode_val;
@@ -372,12 +388,14 @@ GSList *DeviceAgent::get_channels()
  }
 
  bool DeviceAgent::is_stream_mode()
- {
+ { 
     return get_operation_mode() == LO_OP_STREAM;
  }
 
  bool DeviceAgent::check_firmware_version()
  {
+    assert(_dev_handle);
+
     int st = -1;
     if (ds_get_actived_device_init_status(&st) == SR_OK){
         if (st == SR_ST_INCOMPATIBLE){
@@ -387,5 +405,37 @@ GSList *DeviceAgent::get_channels()
     return true;
  }
 
+ QString DeviceAgent::get_demo_operation_mode()
+ {
+    assert(_dev_handle);
+
+    if (is_demo() == false){
+        assert(false);
+    }        
+    
+    QString pattern_mode;
+    if(get_config_value_string(SR_CONF_PATTERN_MODE, pattern_mode) == false)
+    {
+        assert(false);
+    }
+    return pattern_mode;
+ }
+
+ bool DeviceAgent::set_config_string(int key, const char *value)
+ {
+    assert(value);
+    assert(_dev_handle);
+
+    GVariant *gvar = g_variant_new_string(value);
+    int ret = ds_set_actived_device_config(NULL, NULL, key, gvar);
+    if (ret != SR_OK)
+    {
+        if (ret != SR_ERR_NA)
+            dsv_err("%s%d", "ERROR: DeviceAgent::set_config_string, Failed to set value of config id:", key);
+        return false;
+    }
+    return true;
+ }
+
 //---------------device config end -----------/
 
diff --git a/DSView/pv/deviceagent.h b/DSView/pv/deviceagent.h
index 9b927efc..c888c5b0 100644
--- a/DSView/pv/deviceagent.h
+++ b/DSView/pv/deviceagent.h
@@ -105,6 +105,8 @@ public:
 
     bool get_config_value_int16(int key, int &value);
 
+    bool get_config_value_string(int key, QString &value);
+
     /**
 	 * @brief Gets the sample limit from the driver.
 	 *
@@ -183,6 +185,10 @@ public:
 
     bool check_firmware_version();
 
+    QString get_demo_operation_mode();
+
+    bool set_config_string(int key, const char *value);
+
 private:
     void config_changed();
     bool is_in_history(ds_device_handle dev_handle);
diff --git a/DSView/pv/dock/protocoldock.cpp b/DSView/pv/dock/protocoldock.cpp
index 93572c76..cc3af8c4 100644
--- a/DSView/pv/dock/protocoldock.cpp
+++ b/DSView/pv/dock/protocoldock.cpp
@@ -439,6 +439,7 @@ void ProtocolDock::del_all_protocol()
         }
 
         _protocol_lay_items.clear();
+        this->update();
         protocol_updated();
     }
 }
diff --git a/DSView/pv/interface/icallbacks.h b/DSView/pv/interface/icallbacks.h
index 9bc0d655..92f7fb96 100644
--- a/DSView/pv/interface/icallbacks.h
+++ b/DSView/pv/interface/icallbacks.h
@@ -88,6 +88,7 @@ public:
 #define DSV_MSG_NEW_USB_DEVICE          6008
 #define DSV_MSG_CURRENT_DEVICE_DETACHED 6009
 #define DSV_MSG_DEVICE_CONFIG_UPDATED   6010
+#define DSV_MSG_DEMO_OPERATION_MODE_CHNAGED   6011
 
 #define DSV_MSG_TRIG_NEXT_COLLECT       7001
 #define DSV_MSG_SAVE_COMPLETE           7002
diff --git a/DSView/pv/mainwindow.cpp b/DSView/pv/mainwindow.cpp
index 24127fa9..f9c8099d 100644
--- a/DSView/pv/mainwindow.cpp
+++ b/DSView/pv/mainwindow.cpp
@@ -1945,12 +1945,10 @@ namespace pv
             break;  
 
         case DSV_MSG_END_DEVICE_OPTIONS: 
-            if(_device_agent->is_demo() &&_device_agent->get_work_mode() == LOGIC){
-                GVariant *gvar = _device_agent->get_config(NULL,NULL,SR_CONF_PATTERN_MODE);
-                if(gvar != NULL)
+            if(_device_agent->is_demo() &&_device_agent->get_work_mode() == LOGIC){                
+                QString pattern_mode;
+                if(_device_agent->get_config_value_string(SR_CONF_PATTERN_MODE, pattern_mode))
                 {
-                    std::string pattern_mode = g_variant_get_string(gvar,NULL);
-                    g_variant_unref(gvar);
                     if(pattern_mode != _pattern_mode)
                     {
                         _pattern_mode = pattern_mode;
@@ -1965,6 +1963,7 @@ namespace pv
                          
                         if(_pattern_mode != "random")
                         {
+                            _session->set_operation_mode(OPT_SINGLE);
                             StoreSession ss(_session);
                             QJsonArray deArray = get_decoder_json_from_file(_device_agent->path());
                             ss.load_decoders(_protocol_widget, deArray);
@@ -1974,7 +1973,25 @@ namespace pv
                 }
             }
             calc_min_height();            
-            break;                                 
+            break;       
+
+        case DSV_MSG_DEMO_OPERATION_MODE_CHNAGED:
+            if(_device_agent->is_demo() &&_device_agent->get_work_mode() == LOGIC){
+                _protocol_widget->del_all_protocol();
+                _session->clear_view_data();
+                QString pattern_mode;
+
+                if(_device_agent->get_config_value_string(SR_CONF_PATTERN_MODE, pattern_mode)){
+                    if(pattern_mode != "random"){
+                        _device_agent->update();
+                        _session->set_operation_mode(OPT_SINGLE);
+                        StoreSession ss(_session);
+                        QJsonArray deArray = get_decoder_json_from_file(_device_agent->path());
+                        ss.load_decoders(_protocol_widget, deArray);
+                    }
+                }
+            }
+            break;                          
         }
     }
 
diff --git a/DSView/pv/mainwindow.h b/DSView/pv/mainwindow.h
index 411cd74e..ccc22b5b 100644
--- a/DSView/pv/mainwindow.h
+++ b/DSView/pv/mainwindow.h
@@ -221,7 +221,7 @@ private:
     bool            _is_auto_switch_device;
     high_resolution_clock::time_point _last_key_press_time;
     bool            _is_save_confirm_msg;
-    std::string         _pattern_mode;
+    QString         _pattern_mode;
     QWidget         *_frame;
     DsTimer         _delay_prop_msg_timer;
     QString         _strMsg;
diff --git a/DSView/pv/sigsession.cpp b/DSView/pv/sigsession.cpp
index 7b9e9eae..9f577ddc 100644
--- a/DSView/pv/sigsession.cpp
+++ b/DSView/pv/sigsession.cpp
@@ -2296,4 +2296,10 @@ namespace pv
         set_cur_samplelimits(_device_agent.get_sample_limit());
     }
 
+    void SigSession::clear_view_data()
+    {
+        _view_data->clear();
+        data_updated();
+    }
+
 } // namespace pv
diff --git a/DSView/pv/sigsession.h b/DSView/pv/sigsession.h
index 201fd06e..a7eae56b 100644
--- a/DSView/pv/sigsession.h
+++ b/DSView/pv/sigsession.h
@@ -416,6 +416,8 @@ public:
         return _is_action;
     }
 
+    void clear_view_data();
+
 private:
     void set_cur_samplelimits(uint64_t samplelimits);
     void set_cur_snap_samplerate(uint64_t samplerate);
diff --git a/DSView/pv/toolbars/samplingbar.cpp b/DSView/pv/toolbars/samplingbar.cpp
index 24677476..3ee02945 100644
--- a/DSView/pv/toolbars/samplingbar.cpp
+++ b/DSView/pv/toolbars/samplingbar.cpp
@@ -133,9 +133,9 @@ namespace pv
             connect(&_run_stop_button, SIGNAL(clicked()), this, SLOT(on_run_stop()), Qt::DirectConnection);
             connect(&_instant_button, SIGNAL(clicked()), this, SLOT(on_instant_stop()));
             connect(&_sample_count, SIGNAL(currentIndexChanged(int)), this, SLOT(on_samplecount_sel(int)));
-            connect(_action_single, SIGNAL(triggered()), this, SLOT(on_mode()));
-            connect(_action_repeat, SIGNAL(triggered()), this, SLOT(on_mode()));
-            connect(_action_loop, SIGNAL(triggered()), this, SLOT(on_mode()));
+            connect(_action_single, SIGNAL(triggered()), this, SLOT(on_collect_mode()));
+            connect(_action_repeat, SIGNAL(triggered()), this, SLOT(on_collect_mode()));
+            connect(_action_loop, SIGNAL(triggered()), this, SLOT(on_collect_mode()));
             connect(&_sample_rate, SIGNAL(currentIndexChanged(int)), this, SLOT(on_samplerate_sel(int)));
         }
 
@@ -1092,14 +1092,19 @@ namespace pv
             update();
         }
 
-        void SamplingBar::on_mode()
+        void SamplingBar::on_collect_mode()
         {
             QString iconPath = GetIconPath();
             QAction *act = qobject_cast<QAction *>(sender());
 
             if (act == _action_single)
-            { 
+            {  
                 _session->set_operation_mode(OPT_SINGLE);
+
+                if (_device_agent->is_demo()){
+                    _device_agent->set_config_string(SR_CONF_PATTERN_MODE, "protocol");
+                    _session->broadcast_msg(DSV_MSG_DEMO_OPERATION_MODE_CHNAGED);
+                }
             }
             else if (act == _action_repeat)
             { 
@@ -1118,12 +1123,23 @@ namespace pv
                     {
                         _session->set_repeat_intvl(interval_dlg.get_interval());
                         _session->set_operation_mode(OPT_REPEAT);
+                       
                     }
-                }             
+                }
+
+                if (_device_agent->is_demo()){
+                    _device_agent->set_config_string(SR_CONF_PATTERN_MODE, "random");
+                    _session->broadcast_msg(DSV_MSG_DEMO_OPERATION_MODE_CHNAGED);
+                }          
             }
             else if (act == _action_loop)
-            { 
+            {  
                 _session->set_operation_mode(OPT_LOOP);
+
+                if (_device_agent->is_demo()){
+                    _device_agent->set_config_string(SR_CONF_PATTERN_MODE, "random");
+                    _session->broadcast_msg(DSV_MSG_DEMO_OPERATION_MODE_CHNAGED);
+                }
             }
 
             update_mode_icon();
@@ -1222,7 +1238,7 @@ namespace pv
                     }
                 }
                 
-                if (_device_agent->have_instance()){
+                if (mode == LOGIC && _device_agent->is_file() == false){
                     if (_device_agent->is_stream_mode() || _device_agent->is_demo())
                         _action_loop->setVisible(true);
                 }                
@@ -1261,7 +1277,6 @@ namespace pv
                     g_variant_unref(gvar);
 
                     bool is_rand = rand_mode == "random";
-                    _action_loop->setVisible(is_rand);
                     
                     if (!is_rand && mode == LOGIC){
                         _sample_rate.setEnabled(false);
diff --git a/DSView/pv/toolbars/samplingbar.h b/DSView/pv/toolbars/samplingbar.h
index 27c24abb..6a173cf3 100644
--- a/DSView/pv/toolbars/samplingbar.h
+++ b/DSView/pv/toolbars/samplingbar.h
@@ -122,7 +122,7 @@ namespace pv
             void update_mode_icon();
 
         private slots:
-            void on_mode();
+            void on_collect_mode();
             void on_run_stop();
             void on_instant_stop();
             void on_device_selected();