From d939ff7f401624e1a357f97c4d1974063a921695 Mon Sep 17 00:00:00 2001
From: hkiel <henning.kiel@w-hs.de>
Date: Tue, 15 Dec 2015 12:03:39 +0100
Subject: [PATCH] Implement zoom in DocumentationView with ctrl+scroll reset
 zoom to factor 1 with control+doubleClick

---
 .../Modeling/DocumentationWidget.cpp          | 39 +++++++++++++++++++
 .../OMEditGUI/Modeling/DocumentationWidget.h  |  3 ++
 2 files changed, 42 insertions(+)

diff --git a/OMEdit/OMEditGUI/Modeling/DocumentationWidget.cpp b/OMEdit/OMEditGUI/Modeling/DocumentationWidget.cpp
index a01625a7b61..84a614e7c70 100644
--- a/OMEdit/OMEditGUI/Modeling/DocumentationWidget.cpp
+++ b/OMEdit/OMEditGUI/Modeling/DocumentationWidget.cpp
@@ -192,6 +192,8 @@ DocumentationViewer::DocumentationViewer(DocumentationWidget *pParent)
   setContextMenuPolicy(Qt::CustomContextMenu);
   connect(this, SIGNAL(customContextMenuRequested(QPoint)), SLOT(showContextMenu(QPoint)));
   mpDocumentationWidget = pParent;
+  zoomFact = 1.;
+  setZoomFactor(zoomFact);
   // set DocumentationViewer settings
   settings()->setFontFamily(QWebSettings::StandardFont, "Verdana");
   settings()->setFontSize(QWebSettings::DefaultFontSize, 10);
@@ -297,15 +299,52 @@ void DocumentationViewer::keyPressEvent(QKeyEvent *event)
   if (event->modifiers().testFlag(Qt::ShiftModifier) && event->key() == Qt::Key_Backspace)
   {
     if (mpDocumentationWidget->getNextToolButton()->isEnabled())
+    {
       mpDocumentationWidget->nextDocumentation();
+    }
   }
   else if (event->key() == Qt::Key_Backspace)
   {
     if (mpDocumentationWidget->getPreviousToolButton()->isEnabled())
+    {
       mpDocumentationWidget->previousDocumentation();
+    }
   }
   else
   {
     QWebView::keyPressEvent(event);
   }
 }
+
+//! Reimplementation of wheelevent.
+//! Defines what to do for control+scrolling the wheel
+void DocumentationViewer::wheelEvent(QWheelEvent *event)
+{
+  if (event->orientation() == Qt::Vertical && event->modifiers().testFlag(Qt::ControlModifier))
+  {
+      zoomFact+=event->delta()/120.;
+      if (zoomFact > 5.) zoomFact = 5.;
+      if (zoomFact < .1) zoomFact = .1;
+      setZoomFactor(zoomFact);
+  }
+  else
+  {
+    QWebView::wheelEvent(event);
+  }
+}
+
+//! Reimplementation of mousedoubleclickevent.
+//! Defines what to do for control+doubleclick
+void DocumentationViewer::mouseDoubleClickEvent(QMouseEvent *event)
+{
+  if (event->modifiers().testFlag(Qt::ControlModifier))
+  {
+    zoomFact=1.;
+    setZoomFactor(zoomFact);
+  }
+  else
+  {
+    QWebView::mouseDoubleClickEvent(event);
+  }
+}
+
diff --git a/OMEdit/OMEditGUI/Modeling/DocumentationWidget.h b/OMEdit/OMEditGUI/Modeling/DocumentationWidget.h
index e273af6a603..051632a643f 100644
--- a/OMEdit/OMEditGUI/Modeling/DocumentationWidget.h
+++ b/OMEdit/OMEditGUI/Modeling/DocumentationWidget.h
@@ -79,6 +79,7 @@ class DocumentationViewer : public QWebView
   Q_OBJECT
 private:
   DocumentationWidget *mpDocumentationWidget;
+  qreal zoomFact;
 public:
   DocumentationViewer(DocumentationWidget *pParent);
 public slots:
@@ -89,6 +90,8 @@ public slots:
 protected:
   virtual QWebView* createWindow(QWebPage::WebWindowType type);
   virtual void keyPressEvent(QKeyEvent *event);
+  virtual void wheelEvent(QWheelEvent *event);
+  virtual void mouseDoubleClickEvent(QMouseEvent *event);
 };
 
 #endif // DOCUMENTATIONWIDGET_H