ModelEditor: Zoom with Ctrl + mouse wheel

Change-Id: I2e703345a882f0dbd80a0957d5f28bd203f4f26b
Reviewed-by: Tobias Hunger <tobias.hunger@qt.io>
(cherry picked from commit 3e776dde5e)
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/modeleditor/editordiagramview.cpp

@@ -33,6 +33,8 @@
 #include <projectexplorer/projectnodes.h>
 #include <utils/dropsupport.h>
 
+#include <QWheelEvent>
+
 namespace ModelEditor {
 namespace Internal {
 
@@ -63,6 +65,17 @@ void EditorDiagramView::setPxNodeController(PxNodeController *pxNodeController)
     d->pxNodeController = pxNodeController;
 }
 
+void EditorDiagramView::wheelEvent(QWheelEvent *wheelEvent)
+{
+    if (wheelEvent->modifiers() == Qt::ControlModifier) {
+        int degree = wheelEvent->angleDelta().y() / 8;
+        if (degree > 0)
+            emit zoomIn();
+        else if (degree < 0)
+            emit zoomOut();
+    }
+}
+
 void EditorDiagramView::dropProjectExplorerNodes(const QList<QVariant> &values, const QPoint &pos)
 {
     foreach (const QVariant &value, values) {

src/plugins/modeleditor/editordiagramview.h

@@ -40,10 +40,18 @@ class EditorDiagramView :
 
 public:
     explicit EditorDiagramView(QWidget *parent = 0);
-    ~EditorDiagramView();
+    ~EditorDiagramView() override;
 
+signals:
+    void zoomIn();
+    void zoomOut();
+
+public:
     void setPxNodeController(PxNodeController *pxNodeController);
 
+protected:
+    void wheelEvent(QWheelEvent *wheelEvent) override;
+
 private:
     void dropProjectExplorerNodes(const QList<QVariant> &values, const QPoint &pos);
 

src/plugins/modeleditor/modeleditor.cpp

@@ -69,6 +69,7 @@
 #include <coreplugin/editormanager/editormanager.h>
 #include <coreplugin/minisplitter.h>
 #include <coreplugin/actionmanager/commandbutton.h>
+#include <utils/fadingindicator.h>
 #include <utils/styledbar.h>
 #include <utils/qtcassert.h>
 
@@ -376,6 +377,11 @@ void ModelEditor::initDocument()
     connect(Core::EditorManager::instance(), &Core::EditorManager::currentEditorChanged,
             this, &ModelEditor::onCurrentEditorChanged, Qt::QueuedConnection);
 
+    connect(d->diagramView, &EditorDiagramView::zoomIn,
+            this, &ModelEditor::zoomIn);
+    connect(d->diagramView, &EditorDiagramView::zoomOut,
+            this, &ModelEditor::zoomOut);
+
     connect(d->modelTreeView->selectionModel(), &QItemSelectionModel::selectionChanged,
             this, &ModelEditor::onTreeViewSelectionChanged, Qt::QueuedConnection);
     connect(d->modelTreeView, &qmt::ModelTreeView::treeViewActivated,
@@ -564,6 +570,7 @@ void ModelEditor::zoomIn()
     QTransform transform = d->diagramView->transform();
     transform.scale(ZOOM_FACTOR, ZOOM_FACTOR);
     d->diagramView->setTransform(transform);
+    showZoomIndicator();
 }
 
 void ModelEditor::zoomOut()
@@ -571,11 +578,13 @@ void ModelEditor::zoomOut()
     QTransform transform = d->diagramView->transform();
     transform.scale(1.0 / ZOOM_FACTOR, 1.0 / ZOOM_FACTOR);
     d->diagramView->setTransform(transform);
+    showZoomIndicator();
 }
 
 void ModelEditor::resetZoom()
 {
     d->diagramView->setTransform(QTransform());
+    showZoomIndicator();
 }
 
 qmt::MPackage *ModelEditor::guessSelectedPackage() const
@@ -766,6 +775,15 @@ bool ModelEditor::updateButtonIconByTheme(QAbstractButton *button, const QString
     return false;
 }
 
+void ModelEditor::showZoomIndicator()
+{
+    int scale = int(d->diagramView->transform().map(QPointF(100, 100)).x() + 0.5);
+    Utils::FadingIndicator::showText(d->diagramStack,
+                                     QCoreApplication::translate("ModelEditor",
+                                                                 "Zoom: %1%").arg(scale),
+                                     Utils::FadingIndicator::SmallText);
+}
+
 void ModelEditor::onAddPackage()
 {
     ExtDocumentController *documentController = d->document->documentController();

src/plugins/modeleditor/modeleditor.h

@@ -105,6 +105,7 @@ private:
                                         const QIcon &icon,
                                         const QString &toolTipBase, QWidget *parent);
     bool updateButtonIconByTheme(QAbstractButton *button, const QString &name);
+    void showZoomIndicator();
 
     void onAddPackage();
     void onAddComponent();