Implment ctl+/- zoomin on Page

src/Mod/TechDraw/Gui/QGVPage.cpp

@@ -112,6 +112,7 @@ QGVPage::QGVPage(ViewProviderPage *vp, QGraphicsScene* s, QWidget *parent)
         .GetGroup("BaseApp")->GetGroup("Preferences")->GetGroup("View");
     m_atCursor = hGrp->GetBool("ZoomAtCursor", 1l);
     m_invertZoom = hGrp->GetBool("InvertZoom", 0l);
+    m_zoomIncrement = hGrp->GetFloat("ZoomStep",0.02);
 
     if (m_atCursor) {
         setResizeAnchor(AnchorUnderMouse);
@@ -712,6 +713,26 @@ void QGVPage::wheelEvent(QWheelEvent *event)
     event->accept();
 }
 
+void QGVPage::keyPressEvent(QKeyEvent *event)
+{
+    if(event->modifiers().testFlag(Qt::ControlModifier)) {
+        switch(event->key()) {
+            case Qt::Key_Plus: { 
+                scale(1.0 + m_zoomIncrement, 1.0 + m_zoomIncrement);
+                break; 
+            }
+            case Qt::Key_Minus: {
+                scale(1.0 - m_zoomIncrement, 1.0 - m_zoomIncrement);
+                break;
+            }
+            default: {
+                break;
+            }
+        }
+    }
+    event->accept();
+}
+
 void QGVPage::enterEvent(QEvent *event)
 {
     QGraphicsView::enterEvent(event);

src/Mod/TechDraw/Gui/QGVPage.h

@@ -113,6 +113,7 @@ protected:
     void enterEvent(QEvent *event);
     void mousePressEvent(QMouseEvent *event);
     void mouseReleaseEvent(QMouseEvent *event);
+    void keyPressEvent(QKeyEvent *event) override;
 
     static QColor SelectColor;
     static QColor PreselectColor;
@@ -132,6 +133,7 @@ private:
     
     bool m_atCursor;
     bool m_invertZoom;
+    double m_zoomIncrement;
 };
 
 } // namespace MDIViewPageGui