Implement drag'n'drop-related qt5 events, no-op so far

Change-Id: I67b8cecdc85ad77d7ab48d229459a79bc168072d
Reviewed-on: https://gerrit.libreoffice.org/61721
Tested-by: Jenkins
Reviewed-by: Katarina Behrens <Katarina.Behrens@cib.de>

vcl/inc/qt5/Qt5Widget.hxx

@@ -46,6 +46,9 @@ class Qt5Widget : public QWidget
     virtual void mouseMoveEvent(QMouseEvent*) override;
     virtual void mousePressEvent(QMouseEvent*) override;
     virtual void mouseReleaseEvent(QMouseEvent*) override;
+    virtual void dragEnterEvent(QDragEnterEvent*) override;
+    virtual void dragMoveEvent(QDragMoveEvent*) override;
+    virtual void dropEvent(QDropEvent*) override;
     virtual void moveEvent(QMoveEvent*) override;
     virtual void paintEvent(QPaintEvent*) override;
     virtual void resizeEvent(QResizeEvent*) override;
@@ -56,6 +59,7 @@ class Qt5Widget : public QWidget
 public:
     Qt5Widget(Qt5Frame& rFrame, Qt::WindowFlags f = Qt::WindowFlags());
     Qt5Frame* m_pFrame;
+    void startDrag();
 };
 
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */

vcl/qt5/Qt5Widget.cxx

@@ -124,10 +124,12 @@ void Qt5Widget::mouseReleaseEvent(QMouseEvent* pEvent) { handleMouseButtonEvent(
 
 void Qt5Widget::mouseMoveEvent(QMouseEvent* pEvent)
 {
+    QPoint point = pEvent->pos();
+
     SalMouseEvent aEvent;
     aEvent.mnTime = pEvent->timestamp();
-    aEvent.mnX = pEvent->pos().x();
-    aEvent.mnY = pEvent->pos().y();
+    aEvent.mnX = point.x();
+    aEvent.mnY = point.y();
     aEvent.mnCode = GetKeyModCode(pEvent->modifiers()) | GetMouseModCode(pEvent->buttons());
     aEvent.mnButton = 0;
 
@@ -163,6 +165,35 @@ void Qt5Widget::wheelEvent(QWheelEvent* pEvent)
     pEvent->accept();
 }
 
+void Qt5Widget::startDrag()
+{
+    QMimeData* mimeData = new QMimeData;
+    mimeData->setData("application/x-libreoffice-dnditem", nullptr);
+
+    QDrag* drag = new QDrag(this);
+    drag->setMimeData(mimeData);
+    drag->exec(Qt::CopyAction | Qt::MoveAction, Qt::MoveAction);
+}
+
+void Qt5Widget::dragEnterEvent(QDragEnterEvent* event)
+{
+    SAL_WARN("vcl.qt5", "dragenterevent");
+    if (event->source() == this)
+        event->accept();
+}
+
+void Qt5Widget::dragMoveEvent(QDragMoveEvent* event)
+{
+    SAL_WARN("vcl.qt5", "dragmoveevent");
+    QWidget::dragMoveEvent(event);
+}
+
+void Qt5Widget::dropEvent(QDropEvent* event)
+{
+    SAL_WARN("vcl.qt5", "dropevent");
+    QWidget::dropEvent(event);
+}
+
 void Qt5Widget::moveEvent(QMoveEvent*) { m_pFrame->CallCallback(SalEvent::Move, nullptr); }
 
 void Qt5Widget::showEvent(QShowEvent*)
@@ -359,6 +390,7 @@ Qt5Widget::Qt5Widget(Qt5Frame& rFrame, Qt::WindowFlags f)
 {
     create();
     setMouseTracking(true);
+    setAcceptDrops(true);
     setFocusPolicy(Qt::StrongFocus);
 }