exportdialog/timeruler: disable marker and workarea editing

Fixes #1979

app/dialog/export/export.cpp

@@ -182,6 +182,7 @@ ExportDialog::ExportDialog(ViewerOutput *viewer_node, QWidget *parent) :
   QVBoxLayout* preview_layout = new QVBoxLayout(preview_area);
   preview_layout->addWidget(new QLabel(tr("Preview")));
   preview_viewer_ = new ViewerWidget();
+  preview_viewer_->ruler()->SetMarkerEditingEnabled(false);
   preview_viewer_->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
   connect(preview_viewer_, &ViewerWidget::TimeChanged, video_tab_, &ExportVideoTab::SetTime);
   preview_layout->addWidget(preview_viewer_);

app/widget/timeruler/seekablewidget.cpp

@@ -48,7 +48,8 @@ SeekableWidget::SeekableWidget(QWidget* parent) :
   selection_manager_(this),
   resize_item_(nullptr),
   marker_top_(0),
-  marker_bottom_(0)
+  marker_bottom_(0),
+  marker_editing_enabled_(true)
 {
   QFontMetrics fm = fontMetrics();
 
@@ -172,6 +173,8 @@ bool SeekableWidget::PasteMarkers()
 
 void SeekableWidget::mousePressEvent(QMouseEvent *event)
 {
+  TimelineMarker *initial;
+
   if (resize_item_) {
     // Handle selection, even though we won't be using it for dragging
     if (!(event->modifiers() & Qt::ShiftModifier)) {
@@ -182,7 +185,7 @@ void SeekableWidget::mousePressEvent(QMouseEvent *event)
     }
     dragging_ = true;
     resize_start_ = mapToScene(event->pos());
-  } else if (TimelineMarker *initial = selection_manager_.MousePress(event)) {
+  } else if (marker_editing_enabled_ && (initial = selection_manager_.MousePress(event))) {
     selection_manager_.DragStart(initial, event);
   } else if (!selection_manager_.GetObjectAtPoint(event->pos()) && event->button() == Qt::LeftButton) {
     SeekToScenePoint(mapToScene(event->pos()).x());
@@ -430,7 +433,7 @@ int SeekableWidget::GetRightLimit() const
 
 bool SeekableWidget::ShowContextMenu(const QPoint &p)
 {
-  if (selection_manager_.GetObjectAtPoint(p) && !selection_manager_.GetSelectedObjects().empty()) {
+  if (marker_editing_enabled_ && selection_manager_.GetObjectAtPoint(p) && !selection_manager_.GetSelectedObjects().empty()) {
     // Show marker-specific menu
     Menu m;
 
@@ -457,6 +460,10 @@ bool SeekableWidget::ShowContextMenu(const QPoint &p)
 
 bool SeekableWidget::FindResizeHandle(QMouseEvent *event)
 {
+  if (!marker_editing_enabled_) {
+    return false;
+  }
+
   resize_item_ = nullptr;
   resize_mode_ = kResizeNone;
 

app/widget/timeruler/seekablewidget.h

@@ -52,6 +52,9 @@ public:
     return dragging_;
   }
 
+  bool IsMarkerEditingEnabled() const { return marker_editing_enabled_; }
+  void SetMarkerEditingEnabled(bool e) { marker_editing_enabled_ = e; }
+
   void DeleteSelected();
 
   bool CopySelected(bool cut);
@@ -143,6 +146,8 @@ private:
   int marker_top_;
   int marker_bottom_;
 
+  bool marker_editing_enabled_;
+
 private slots:
   void SetMarkerColor(int c);