can update a demo trace when started run.

mainwindow.cpp

@@ -8,9 +8,9 @@
 #include <QDir>
 #include <QFile>
 #include <QProcess>
+#include <QRandomGenerator>
 
 #include <QChartView>
-#include <QLineSeries>
 #include <QValueAxis>
 
 #include <unistd.h>
@@ -30,7 +30,7 @@ MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent){
   digiSetting = NULL;
   readDataThread = NULL;
 
-  plot = new QChart();
+  SetUpPlot();
 
   QWidget * mainLayoutWidget = new QWidget(this);
   setCentralWidget(mainLayoutWidget);
@@ -183,7 +183,13 @@ MainWindow::~MainWindow(){
   //delete bnNewExp;
   //delete logInfo;
 
-  if( plot != NULL )delete plot;
+  updateTraceThread->Stop();
+  updateTraceThread->quit();
+  updateTraceThread->wait();
+  delete updateTraceThread;
+
+  delete dataTrace; /// dataTrace must be deleted before plot
+  delete plot;
 
   //---- need manually delete
   if( digiSetting != NULL ) delete digiSetting;
@@ -214,11 +220,17 @@ void MainWindow::StartACQ(){
   bnStartACQ->setEnabled(false);
   bnStopACQ->setEnabled(true);
 
+  updateTraceThread->start();
+
   LogMsg("end of " + QString::fromStdString(__func__));
 }
 
 void MainWindow::StopACQ(){
 
+  updateTraceThread->Stop();
+  updateTraceThread->quit();
+  updateTraceThread->wait();
+
   for( int i = 0; i < nDigi; i++){
     if( digi[i]->IsDummy () ) continue;
     digi[i]->StopACQ();
@@ -301,7 +313,6 @@ void MainWindow::CloseDigitizers(){
     if( digiSetting != NULL )  digiSetting->close(); 
 
     if( readDataThread[i] != NULL ){
-      readDataThread[i]->Stop();
       readDataThread[i]->quit();
       readDataThread[i]->wait();
       delete readDataThread[i];
@@ -319,45 +330,54 @@ void MainWindow::CloseDigitizers(){
 //^###################################################################### Open Scope
 void MainWindow::OpenScope(){
 
-  QMainWindow * scope = new QMainWindow(this);
-  scope->setWindowTitle("Scope");
-  scope->setGeometry(0, 0, 1000, 800);  
-
   QWidget * layoutWidget = new QWidget(scope);
   scope->setCentralWidget(layoutWidget);
   QGridLayout * layout = new QGridLayout(layoutWidget);
   layoutWidget->setLayout(layout);
 
-
-  plot->removeAllSeries();
-
-  QLineSeries * data = new QLineSeries(this);
-  data->setName("data");
-
-  //--------- add data
-  data->append(1, 2);
-  data->append(2, 2);
-  data->append(3, 5);
-  data->append(4, 2);
-
-  plot->addSeries(data);
-
-
-  plot->createDefaultAxes(); /// this must be after addSeries();
-  plot->axes(Qt::Vertical).first()->setRange(0, 10); /// this must be after createDefaultAxes();
-  plot->axes(Qt::Horizontal).first()->setRange(0, 5);
-
   QChartView * plotView = new QChartView(plot);
   plotView->setRenderHints(QPainter::Antialiasing);
   
   //scope->setCentralWidget(plotView);
-  layout->addWidget(plotView);
+  layout->addWidget(plotView, 0, 0);
 
+  QPushButton * bnUpdate = new QPushButton("Random", scope);
+  layout->addWidget(bnUpdate, 1, 0);
+  connect(bnUpdate, &QPushButton::clicked, this, &MainWindow::UpdateScope);
 
   scope->show();
 
 }
 
+void MainWindow::SetUpPlot(){ //@--- this function run at start up
+  scope = new QMainWindow(this);
+  scope->setWindowTitle("Scope");
+  scope->setGeometry(0, 0, 1000, 800);  
+
+  plot = new QChart();
+  dataTrace = new QLineSeries();
+  dataTrace->setName("data");
+  for(int i = 0; i < 100; i ++) dataTrace->append(i, QRandomGenerator::global()->bounded(10));
+  plot->addSeries(dataTrace);
+  plot->createDefaultAxes(); /// this must be after addSeries();
+  plot->axes(Qt::Vertical).first()->setRange(-1, 11); /// this must be after createDefaultAxes();
+  plot->axes(Qt::Horizontal).first()->setRange(-1, 101);
+
+  updateTraceThread = new UpdateTraceThread();
+  connect(updateTraceThread, &UpdateTraceThread::updateTrace, this, &MainWindow::UpdateScope);
+
+}
+
+void MainWindow::UpdateScope(){
+
+  if( scope->isVisible() == false) return;
+
+  for( int i = 0 ; i < dataTrace->count(); i++){
+    dataTrace->replace(i, i, QRandomGenerator::global()->bounded(10));
+  }
+
+}
+
 //^###################################################################### Open digitizer setting panel
 void MainWindow::OpenDigitizersSettings(){
   LogMsg("Open digitizers Settings Panel");

mainwindow.h

@@ -12,6 +12,7 @@
 #include <QPushButton>
 #include <QMutex>
 #include <QChart>
+#include <QLineSeries>
 
 #include <vector>
 #include <time.h> // time in nano-sec
@@ -23,27 +24,15 @@
 
 static QMutex digiMTX;
 
-class ReadDataThread : public QThread{
+//^#===================================================== ReadData Thread
+class ReadDataThread : public QThread {
   Q_OBJECT
-
 public:
   ReadDataThread(Digitizer2Gen * dig, QObject * parent = 0) : QThread(parent){ 
-    stop = false;
     this->digi = dig;
-    readCount = 0;
   }
-
-  void Stop() {stop = true;}
-
   void run(){
     clock_gettime(CLOCK_REALTIME, &ta);
-    readCount = 0;
-
-    //for( int i = 0; i < 10; i ++){
-    //  emit sendMsg(QString::number(i));
-    //  if( stop ) break;
-    //}
-
     while(true){
       digiMTX.lock();
       int ret = digi->ReadData();
@@ -59,32 +48,52 @@ public:
       }
 
       clock_gettime(CLOCK_REALTIME, &tb);
-      //if( readCount % 1000 == 0 ) {
       if( tb.tv_sec - ta.tv_sec > 2 ) {
         emit sendMsg("FileSize : " +  QString::number(digi->GetFileSize()/1024./1024.) + " MB");
+        
         //double duration = tb.tv_nsec-ta.tv_nsec + tb.tv_sec*1e+9 - ta.tv_sec*1e+9;
         //printf("%4d, duration : %10.0f, %6.1f\n", readCount, duration, 1e9/duration);
         ta = tb;
       }
-      readCount++;
-
     }
-
   }
-
 signals:
   void sendMsg(const QString &msg);
+private:
+  Digitizer2Gen * digi; 
+  timespec ta, tb;
+};
+
+//^#===================================================== UpdateTrace Thread
+class UpdateTraceThread : public QThread {
+  Q_OBJECT
+public:
+  UpdateTraceThread(QObject * parent = 0) : QThread(parent){
+    waitTime = 5;
+    stop = false;
+  }
+  void Stop() {this->stop = true;}
+  void run(){
+    unsigned int count = 0;
+    stop = false;
+    do{
+      usleep(100000);
+      count ++;
+      if( count % waitTime == 0){
+        emit updateTrace();
+      }
+    }while(!stop);
+  }
+signals:
+  void updateTrace();
 
 private:
   bool stop;
-  Digitizer2Gen * digi; 
+  unsigned int waitTime; //100 of milisec
-  timespec ta, tb;
-  unsigned int readCount;
-
 };
 
-//=================================================
 
+//^#===================================================== MainWindow
 class MainWindow : public QMainWindow{
   Q_OBJECT
 
@@ -99,10 +108,11 @@ private slots:
   void CloseDigitizers();
   
   void OpenScope();
+  void SetUpPlot();
+  void UpdateScope();
 
   void OpenDigitizersSettings();
 
-
   void ProgramSettings();
   bool OpenProgramSettings();
   void SaveProgramSettings();
@@ -116,7 +126,6 @@ private slots:
 
 signals :
 
-
 private:
     
   QPushButton * bnProgramSettings;
@@ -129,8 +138,11 @@ private:
   QPushButton * bnDigiSettings;
   QPushButton * bnSOLSettings;
 
+  QMainWindow * scope;
   QPushButton * bnOpenScope;
   QChart      * plot;
+  QLineSeries * dataTrace;
+  UpdateTraceThread * updateTraceThread;
 
   QPushButton * bnStartACQ;
   QPushButton * bnStopACQ;