From 1b83bfb7f0b011ac8adefb3307625928436e74d4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?P=C3=A5l=20Hagen?= <pal@applicano.com>
Date: Thu, 22 Oct 2015 14:42:05 +0200
Subject: [PATCH] (#467) Handling drag move events to get the proposed drop
 action

The tree view model's drag & drop handle is notified about the proposed
action in drag move events.
---
 Fwk/AppFwk/cafUserInterface/cafPdmUiDragDropHandle.h |  1 +
 Fwk/AppFwk/cafUserInterface/cafPdmUiTreeViewEditor.h | 12 ++++++++++++
 .../cafUserInterface/cafPdmUiTreeViewModel.cpp       | 12 ++++++++++++
 Fwk/AppFwk/cafUserInterface/cafPdmUiTreeViewModel.h  |  3 +++
 4 files changed, 28 insertions(+)

diff --git a/Fwk/AppFwk/cafUserInterface/cafPdmUiDragDropHandle.h b/Fwk/AppFwk/cafUserInterface/cafPdmUiDragDropHandle.h
index ba8cfcb4a4..4d298b61e4 100644
--- a/Fwk/AppFwk/cafUserInterface/cafPdmUiDragDropHandle.h
+++ b/Fwk/AppFwk/cafUserInterface/cafPdmUiDragDropHandle.h
@@ -58,6 +58,7 @@ public:
     virtual QMimeData*          mimeData(const QModelIndexList &indexes) const = 0;
     virtual QStringList         mimeTypes() const = 0;
     virtual void                endDrag() = 0;
+    virtual void                setProposedAction(Qt::DropAction action) = 0;
 };
 
 inline PdmUiDragDropHandle::~PdmUiDragDropHandle() { }
diff --git a/Fwk/AppFwk/cafUserInterface/cafPdmUiTreeViewEditor.h b/Fwk/AppFwk/cafUserInterface/cafPdmUiTreeViewEditor.h
index a3e1f2a6eb..c76a2e7d6c 100644
--- a/Fwk/AppFwk/cafUserInterface/cafPdmUiTreeViewEditor.h
+++ b/Fwk/AppFwk/cafUserInterface/cafPdmUiTreeViewEditor.h
@@ -87,6 +87,16 @@ public:
     virtual ~PdmUiTreeViewWidget() {};
 
 protected:
+    virtual void dragMoveEvent(QDragMoveEvent* event)
+    {
+        caf::PdmUiTreeViewModel* treeViewModel = dynamic_cast<caf::PdmUiTreeViewModel*>(model());
+        if (treeViewModel)
+        {
+            treeViewModel->updateDragDropHandleFromEvent(event);
+        }
+
+        QTreeView::dragMoveEvent(event);
+    }
     virtual void dragLeaveEvent(QDragLeaveEvent* event)
     {
         caf::PdmUiTreeViewModel* treeViewModel = dynamic_cast<caf::PdmUiTreeViewModel*>(model());
@@ -94,6 +104,8 @@ protected:
         {
             treeViewModel->endDrag();
         }
+
+        QTreeView::dragLeaveEvent(event);
     }
 };
 
diff --git a/Fwk/AppFwk/cafUserInterface/cafPdmUiTreeViewModel.cpp b/Fwk/AppFwk/cafUserInterface/cafPdmUiTreeViewModel.cpp
index 478bc2aaab..0b570d2310 100644
--- a/Fwk/AppFwk/cafUserInterface/cafPdmUiTreeViewModel.cpp
+++ b/Fwk/AppFwk/cafUserInterface/cafPdmUiTreeViewModel.cpp
@@ -45,6 +45,7 @@
 #include "cafPdmUiTreeViewEditor.h"
 
 #include <QTreeView>
+#include <QDragMoveEvent>
 
 namespace caf
 {
@@ -794,6 +795,17 @@ void PdmUiTreeViewModel::setDragDropHandle(PdmUiDragDropHandle* dragDropHandle)
     m_dragDropHandle = dragDropHandle;
 }
 
+//--------------------------------------------------------------------------------------------------
+/// 
+//--------------------------------------------------------------------------------------------------
+void PdmUiTreeViewModel::updateDragDropHandleFromEvent(const QDragMoveEvent* event)
+{
+    if (m_dragDropHandle && event)
+    {
+        m_dragDropHandle->setProposedAction(event->proposedAction());
+    }
+}
+
 //--------------------------------------------------------------------------------------------------
 /// 
 //--------------------------------------------------------------------------------------------------
diff --git a/Fwk/AppFwk/cafUserInterface/cafPdmUiTreeViewModel.h b/Fwk/AppFwk/cafUserInterface/cafPdmUiTreeViewModel.h
index a5d5ee9ec8..184535471d 100644
--- a/Fwk/AppFwk/cafUserInterface/cafPdmUiTreeViewModel.h
+++ b/Fwk/AppFwk/cafUserInterface/cafPdmUiTreeViewModel.h
@@ -41,6 +41,8 @@
 #include <QAbstractItemModel>
 #include <QStringList>
 
+class QDragMoveEvent;
+
 namespace caf
 {
 
@@ -74,6 +76,7 @@ public:
     QModelIndex             findModelIndex(const PdmUiItem* object) const;
 
     void                    setDragDropHandle(PdmUiDragDropHandle* dragDropHandle);
+    void                    updateDragDropHandleFromEvent(const QDragMoveEvent* event);
     void                    endDrag();
     
 private: