OK、多くの調査の後、私は解決策を見つけました:
protected override void OnMouseUp(System.Windows.Input.MouseButtonEventArgs e)
{
Point pt = PointToScreen(Mouse.GetPosition(this));
UIElement canvas = LogicalTreeHelper.GetParent(AdornedElement) as UIElement;
// This is important to get the mouse position relative to the canvas, otherwise it won't work
pt = canvas.PointFromScreen(pt);
VisualTreeHelper.HitTest(canvas, null, HitTestResultCallbackHandler, new PointHitTestParameters(pt));
}
そして、GraphNode を見つけるための HitTest メソッド。GraphNode はカスタム オブジェクトであることを思い出してください。
public HitTestResultBehavior HitTestResultCallbackHandler(HitTestResult result)
{
if (result != null)
{
// Search for elements that have GraphNode as parent
DependencyObject dobj = VisualTreeHelper.GetParent(result.VisualHit);
while (dobj != null && !(dobj is ContentControl))
{
dobj = VisualTreeHelper.GetParent(dobj);
}
ContentControl cc = dobj as ContentControl;
if (!ReferenceEquals(cc, null))
{
IEnumerable<DependencyObject> dependencyObjects = cc.GetSelfAndAncestors();
if (dependencyObjects.Count() > 0)
{
IEnumerable<ContentControl> contentControls = dependencyObjects.Where(x => x.GetType() == typeof(ContentControl)).Cast<ContentControl>();
if (contentControls.Count() > 0)
{
ContentControl cControl = contentControls.FirstOrDefault(x => x.Content.GetType() == typeof(GraphNode));
if (cControl != null)
{
var graphNode = cControl.Content as GraphNode;
if (!ReferenceEquals(graphNode, null))
{
// Keep the result in a local variable
m_DestinationNode = graphNode;
return HitTestResultBehavior.Stop;
}
}
}
}
}
}
m_DestinationNode = null;
return HitTestResultBehavior.Continue;
}