fixed some issues introduced with last commit on selection

src/document/UBDocumentController.cpp

@@ -1401,7 +1401,6 @@ void UBDocumentTreeView::hSliderRangeChanged(int min, int max)
 void UBDocumentTreeView::mousePressEvent(QMouseEvent *event)
 {
     QTreeView::mousePressEvent(event);
-    UBApplication::documentController->updateActions();
 }
 
 void UBDocumentTreeView::dragEnterEvent(QDragEnterEvent *event)
@@ -1942,9 +1941,11 @@ void UBDocumentController::TreeViewSelectionChanged(const QModelIndex &current,
     //We have just to pass a null proxy to disable the display of thumbnail
     UBDocumentProxy *currentDocumentProxy = 0;
 
-    if(current_index.isValid() && mDocumentUI->documentTreeView->selectionModel()->selectedRows(0).size() == 1){
+    if(current_index.isValid() && mDocumentUI->documentTreeView->selectionModel()->selectedRows(0).size() == 1)
+    {
         currentDocumentProxy = docModel->proxyData(current_index);
         setDocument(currentDocumentProxy, false);
+        clearThumbnailsSelection();
     }
     //N/C - NNE  - 20140414 : END
 
@@ -3907,3 +3908,8 @@ void UBDocumentController::expandAll()
 
     mDocumentUI->documentTreeView->setAnimated(true);
 }
+
+void UBDocumentController::clearThumbnailsSelection()
+{
+    mDocumentUI->thumbnailWidget->clearSelection();
+}

src/document/UBDocumentController.h

@@ -458,6 +458,8 @@ class UBDocumentController : public UBDocumentContainer
         QModelIndex findNextSiblingNotSelected(const QModelIndex &index, QItemSelectionModel *selectionModel);
         bool parentIsSelected(const QModelIndex& child, QItemSelectionModel *selectionModel);
 
+        void clearThumbnailsSelection();
+
     signals:
         void exportDone();
         void reorderDocumentsRequested();

src/gui/UBThumbnailWidget.cpp

@@ -232,6 +232,11 @@ QList<QGraphicsItem*> UBThumbnailWidget::selectedItems()
     return sortedSelectedItems;
 }
 
+void UBThumbnailWidget::clearSelection()
+{
+    mThumbnailsScene.clearSelection();
+}
+
 
 void UBThumbnailWidget::mousePressEvent(QMouseEvent *event)
 {

src/gui/UBThumbnailWidget.h

@@ -66,6 +66,7 @@ class UBThumbnailWidget : public QGraphicsView
         QList<QGraphicsItem*> selectedItems();
         void selectItemAt(int pIndex, bool extend = false);
         void unselectItemAt(int pIndex);
+        void clearSelection();
 
         qreal thumbnailWidth()
         {