Question

I have a WPF ParentUserControl and some ChildUserControlA ChildUserControlB etc. (also WPF controls)

The ChildUserControls are controls containing on them some other basic elements (textboxes, labels, etc)

In the main form’s status bar I need to display the name of the currenlty mouse overed ChildUserControl.

So, in the ParentUserControl‘s MouseMove I obtain an object myElement = Mouse.DirectlyOver because I need the top most of ChildUserControl‘s, but I obtain instead a ‘System.Windows.Controls.TextBlock’ (part of ChildUserControl)…

How to fix that?

I need when I mouseOver an MyChildControl that the MyChildControl be detected, and not its child elements.

In this order I used on MyChildControl the following:

Protected Overrides Function HitTestCore(
                    hitTestParameters As PointHitTestParameters) As HitTestResult

    Return New PointHitTestResult(Me, hitTestParameters.HitPoint)
End Function

but anyway I get sometimes the textblock as result, sometimes the ChildUserControl…

Answer 1

Another answer may be something like this – define the exact types of objects you care about and work up the visual tree until you find them :

Private myTypes As New List(Of Type)()
Public Sub New()
    InitializeComponent()
    myTypes.Add(GetType(ComboBox))
    myTypes.Add(GetType(CheckBox))
    myTypes.Add(GetType(RadioButton))
    myTypes.Add(GetType(TabControl))
    myTypes.Add(GetType(Button))
    myTypes.Add(GetType(Label))
    myTypes.Add(GetType(GroupBox))
    myTypes.Add(GetType(Window))
End Sub

Private Sub Window_MouseMove(sender As Object, e As MouseEventArgs)
    Dim x As DependencyObject = _
      DirectCast(e.MouseDevice.DirectlyOver, DependencyObject)
    Dim t As Type = x.GetType
    While Not myTypes.Contains(t)
         x = VisualTreeHelper.GetParent(x)
         If x Is Nothing Then Exit While
         t = x.GetType
    End While

    If x IsNot Nothing Then
          Console.WriteLine(x.ToString())
    Else
          Console.WriteLine("Nothing")
    End If
End Sub