add Zoom in Scope

scope.cpp

@@ -3,11 +3,9 @@
 #include <QValueAxis>
 #include <QRandomGenerator>
 #include <QGroupBox>
-#include <QChartView>
 #include <QStandardItemModel>
 #include <QLabel>
 
-
 Scope::Scope(Digitizer2Gen **digi, unsigned int nDigi, ReadDataThread ** readDataThread, QMainWindow *parent) : QMainWindow(parent){
   this->digi = digi;
   this->nDigi = nDigi;
@@ -19,11 +17,11 @@ Scope::Scope(Digitizer2Gen **digi, unsigned int nDigi, ReadDataThread ** readDat
 
   allowChange = false;
 
-  plot = new QChart();
+  plot = new Trace();
   for( int i = 0; i < 6; i++) {
     dataTrace[i] = new QLineSeries();
     dataTrace[i]->setName("Trace " + QString::number(i));
-    for(int j = 0; j < 100; j ++) dataTrace[i]->append(j, QRandomGenerator::global()->bounded(8000) + 8000);
+    for(int j = 0; j < 100; j ++) dataTrace[i]->append(40*j, QRandomGenerator::global()->bounded(8000) + 8000);
     plot->addSeries(dataTrace[i]);
   }
 
@@ -34,6 +32,7 @@ Scope::Scope(Digitizer2Gen **digi, unsigned int nDigi, ReadDataThread ** readDat
   dataTrace[4]->setPen(QPen(Qt::darkGreen, 1));
   dataTrace[5]->setPen(QPen(Qt::darkBlue, 1));
 
+  plot->setAnimationOptions(QChart::SeriesAnimations);
   plot->createDefaultAxes(); /// this must be after addSeries();
   /// this must be after createDefaultAxes();
   QValueAxis * yaxis = qobject_cast<QValueAxis*> (plot->axes(Qt::Vertical).first());
@@ -320,7 +319,7 @@ Scope::Scope(Digitizer2Gen **digi, unsigned int nDigi, ReadDataThread ** readDat
 
   //------------ plot view
   rowID ++;
-  QChartView * plotView = new QChartView(plot);
+  TraceView * plotView = new TraceView(plot);
   plotView->setRenderHints(QPainter::Antialiasing);
   layout->addWidget(plotView, rowID, 0, 1, 6);
 

scope.h

@@ -4,16 +4,99 @@
 
 #include <QMainWindow>
 #include <QChart>
+#include <QChartView>
 #include <QSpinBox>
 #include <QPushButton>
 #include <QCheckBox>
 #include <QComboBox>
 #include <QGridLayout>
 #include <QLineSeries>
+#include <QRubberBand>
+#include <QMouseEvent>
+#include <QGestureEvent>
 
 #include "ClassDigitizer2Gen.h"
 #include "manyThread.h"
 
+class Trace : public QChart{
+public:
+  explicit Trace(QGraphicsItem *parent = nullptr, Qt::WindowFlags wFlags = {})
+    : QChart(QChart::ChartTypeCartesian, parent, wFlags){
+    grabGesture(Qt::PanGesture);
+    grabGesture(Qt::PinchGesture);
+  }
+  ~Trace(){}
+
+protected:
+  bool sceneEvent(QEvent *event){
+    if (event->type() == QEvent::Gesture) return gestureEvent(static_cast<QGestureEvent *>(event));
+    return QChart::event(event);
+  }
+
+private:
+  bool gestureEvent(QGestureEvent *event){
+    if (QGesture *gesture = event->gesture(Qt::PanGesture)) {
+      QPanGesture *pan = static_cast<QPanGesture *>(gesture);
+      QChart::scroll(-(pan->delta().x()), pan->delta().y());
+    }
+
+    if (QGesture *gesture = event->gesture(Qt::PinchGesture)) {
+      QPinchGesture *pinch = static_cast<QPinchGesture *>(gesture);
+      if (pinch->changeFlags() & QPinchGesture::ScaleFactorChanged) QChart::zoom(pinch->scaleFactor());
+    }
+    return true;
+  }
+
+private:
+
+};
+
+class TraceView : public QChartView{
+public:
+  TraceView(QChart * chart, QWidget * parent = nullptr): QChartView(chart, parent){
+    m_isTouching = false;
+    this->setRubberBand(QChartView::RectangleRubberBand);
+  }
+
+protected:
+  bool viewportEvent(QEvent *event){
+    if (event->type() == QEvent::TouchBegin) {
+      m_isTouching = true;
+      chart()->setAnimationOptions(QChart::NoAnimation);
+    }
+    return QChartView::viewportEvent(event);
+  }
+  void mousePressEvent(QMouseEvent *event){
+    if (m_isTouching) return;
+    QChartView::mousePressEvent(event);
+  }
+  void mouseMoveEvent(QMouseEvent *event){
+    if (m_isTouching) return;
+    QChartView::mouseMoveEvent(event);
+  }
+  void mouseReleaseEvent(QMouseEvent *event){
+    if (m_isTouching)  m_isTouching = false;
+    chart()->setAnimationOptions(QChart::SeriesAnimations);
+    QChartView::mouseReleaseEvent(event);
+  }
+  void keyPressEvent(QKeyEvent *event){
+    switch (event->key()) {
+      case Qt::Key_Plus:  chart()->zoomIn(); break;
+      case Qt::Key_Minus: chart()->zoomOut(); break;
+      case Qt::Key_Left:  chart()->scroll(-10, 0); break;
+      case Qt::Key_Right: chart()->scroll(10, 0); break;
+      case Qt::Key_Up: chart()->scroll(0, 10); break;
+      case Qt::Key_Down: chart()->scroll(0, -10);  break;
+      case Qt::Key_R : chart()->axes(Qt::Vertical).first()->setRange(-16384, 65536); break;
+      default: QGraphicsView::keyPressEvent(event); break;
+    }
+  }
+
+private:
+  bool m_isTouching;
+};
+
+
 class Scope : public QMainWindow{
   Q_OBJECT