curvewidget: connect snapping subsystem

app/widget/curvewidget/curvewidget.cpp

@@ -93,6 +93,7 @@ CurveWidget::CurveWidget(QWidget *parent) :
 
   view_ = new CurveView();
   ConnectTimelineView(view_);
+  view_->SetSnapService(this);
   ruler_view_layout->addWidget(view_);
 
   layout->addLayout(ruler_view_layout);

app/widget/curvewidget/curvewidget.h

@@ -67,6 +67,16 @@ protected:
 
   virtual void ConnectedNodeChangeEvent(ViewerOutput* n) override;
 
+  virtual const QVector<KeyframeViewInputConnection*> *GetSnapKeyframes() const override
+  {
+    return &view_->GetKeyframeTracks();
+  }
+
+  virtual const std::vector<NodeKeyframe*> *GetSnapIgnoreKeyframes() const override
+  {
+    return &view_->GetSelectedKeyframes();
+  }
+
 private:
   void SetKeyframeButtonEnabled(bool enable);