Smrf.NodeXL.Visualization.Wpf.NodeXLControl.OnMouseDown C# (CSharp) Method

    OnMouseDown
    (
        MouseButtonEventArgs e
    )
    {
        AssertValid();

        // Do nothing if the drawing isn't in a stable state.

        if (this.IsLayingOutGraph)
        {
            return;
        }

        // Remove any vertex tooltip that might exist and reset the helper
        // object that figures out when to show tooltips.

        ResetVertexToolTipTracker();

        if ( DragMightBeInProgress() )
        {
            // This can occur if the user clicks another button while dragging
            // with the left button.

            return;
        }

        // Check whether the user clicked on a vertex.

        Point oMouseLocation = e.GetPosition(this);
        IVertex oClickedVertex;

        Boolean bVertexClicked =
            TryGetVertexFromPoint(oMouseLocation, out oClickedVertex);

        FireGraphMouseDown(e, oClickedVertex);

        if (bVertexClicked)
        {
            FireVertexClick(oClickedVertex);

            if (e.ClickCount == 2)
            {
                FireVertexDoubleClick(oClickedVertex);
            }
        }

        // Some drag operations can be cancelled with the Escape key, so
        // capture keyboard focus.

        Keyboard.Focus(this);

        if (m_eMouseMode == MouseMode.DoNothing)
        {
            return;
        }

        switch (e.ChangedButton)
        {
            case MouseButton.Left:

                OnMouseDownLeft(e, oMouseLocation, oClickedVertex);
                break;

            case MouseButton.Middle:

                OnMouseDownMiddle(oMouseLocation);
                break;

            case MouseButton.Right:

                OnMouseDownRight(oMouseLocation, oClickedVertex);
                break;

            default:

                break;
        }
    }