/// <summary>
/// Initializes a new instance of the <see cref="ConnectionCreationBehavior"/> class.
/// </summary>
/// <param name="pParent">The behavior parent view.</param>
/// <param name="pWorkingCanvas">The canvas containing the connection line to work with.</param>
public ConnectionCreationBehavior(SimpleGraphView pParent, Canvas pWorkingCanvas)
: base(pParent)
{
this.WorkingCanvas = pWorkingCanvas;
this.WorkingCanvas.Visibility = Visibility.Collapsed;
this.ConnectingLine.Visibility = Visibility.Collapsed;
this.mSourceConnector = null;
this.mTargetConnector = null;
}
/// <summary>
/// This method is called when a mouse button up occured on the adorner.
/// </summary>
/// <param name="pEventArgs">The event arguments</param>
protected override void OnMouseUp(MouseButtonEventArgs pEventArgs)
{
// Release the mouse capture.
if (this.IsMouseCaptured)
{
this.ReleaseMouseCapture();
}
// Getting the position.
Point lHitPoint = pEventArgs.GetPosition(this);
AdornerLayeredCanvas lParentCanvas = this.AdornedElement as AdornerLayeredCanvas;
if (lParentCanvas != null)
{
// Remove the adorner.
AdornerLayer lLayer = lParentCanvas.AdornerLayer;
if (lLayer != null)
{
lLayer.Remove(this);
}
// Hitting the target connector.
InputConnector lTargetConnector = lParentCanvas.HitControl <InputConnector>(lHitPoint);
if (lTargetConnector != null)
{
GraphViewModel lGraphViewModel = lParentCanvas.DataContext as GraphViewModel;
if (lGraphViewModel != null)
{
PortViewModel lTargetViewModel = lTargetConnector.ParentPort.Content as PortViewModel;
PortViewModel lSourceViewModel = this.mSourceConnector.ParentPort.Content as PortViewModel;
if (lTargetViewModel != null && lSourceViewModel.CanBeConnectedTo(lTargetViewModel))
{
ConnectionViewModel lConnectionViewModel = new ConnectionViewModel();
lConnectionViewModel.Output = lSourceViewModel;
lConnectionViewModel.Input = lTargetViewModel;
lGraphViewModel.AddConnection(lConnectionViewModel);
}
}
}
}
}
/// <summary>
/// Delegate called when the mouse isup on the working canvas.
/// </summary>
/// <param name="pSender">The event sender.</param>
/// <param name="pEventArgs">The event arguments.</param>
private void OnWorkingCanvasMouseUp(object pSender, MouseButtonEventArgs pEventArgs)
{
// Release the mouse capture.
this.WorkingCanvas.ReleaseMouseCapture();
this.WorkingCanvas.MouseMove -= this.OnWorkingCanvasMouseMove;
this.WorkingCanvas.MouseUp -= this.OnWorkingCanvasMouseUp;
this.WorkingCanvas.Visibility = Visibility.Collapsed;
this.ConnectingLine.Visibility = Visibility.Collapsed;
// Trying to create the final connection.
if (this.mSourceConnector != null && this.mTargetConnector != null)
{
// Both defined means the connection can be created. Test have been made in the mouse move event handler.
GraphViewModel lGraphViewModel = this.ParentView.DataContext as GraphViewModel;
if (lGraphViewModel == null)
{
return;
}
PortViewModel lSourceViewModel = this.mSourceConnector.ParentPort.Content as PortViewModel;
PortViewModel lTargetViewModel = this.mTargetConnector.ParentPort.Content as PortViewModel;
ConnectionViewModel lConnectionViewModel = new ConnectionViewModel();
lConnectionViewModel.Output = lSourceViewModel;
lConnectionViewModel.Input = lTargetViewModel;
lGraphViewModel.AddConnection(lConnectionViewModel);
}
// Forget the reference on connectors.
this.mSourceConnector = null;
this.mTargetConnector = null;
}
/// <summary>
/// Delegate called when the mouse move on the working canvas.
/// </summary>
/// <param name="pSender">The event sender.</param>
/// <param name="pEventArgs">The event arguments.</param>
private void OnWorkingCanvasMouseMove(object pSender, MouseEventArgs pEventArgs)
{
if (pEventArgs.LeftButton == MouseButtonState.Pressed)
{
// Create a path according to the source and the end.
this.ConnectingLine.To = pEventArgs.GetPosition(this.WorkingCanvas);
// Updating the cursor.
this.mTargetConnector = this.TryHitInputConnector();
if (this.mTargetConnector != null)
{
PortViewModel lTargetViewModel = this.mTargetConnector.ParentPort.Content as PortViewModel;
PortViewModel lSourceViewModel = this.mSourceConnector.ParentPort.Content as PortViewModel;
if (lSourceViewModel.CanBeConnectedTo(lTargetViewModel))
{
this.WorkingCanvas.Cursor = Cursors.Cross;
}
else
{
this.WorkingCanvas.Cursor = Cursors.No;
this.mTargetConnector = null;
}
}
else
{
this.WorkingCanvas.Cursor = Cursors.Cross;
}
}
}
