How to Get Listbox Selected Item in DragOver Event
I Have two listboxes when I drag One item from the source listbox I would like for the destination listbox to select the item based off the mouse position over the listbox. I have this implemented but the MouseOver event only fires when you are not dragging. How do I select the item based off the dragOver invent of the listbox.
Here is the code
Private Sub CasesBox2_DragEnter(sender As Object, e As System.Windows.DragEventArgs) Handles CasesBox2.DragEnter
CasesBox2.CaptureMouse()
If Not e.Data.GetDataPresent("contact") OrElse sender = e.Source Then
e.Effects = DragDropEffects.None
Else
e.Effects = DragDropEffects.All
End If
End Sub
Private Sub CasesBox2_DragOver(sender As Object, e As System.Windows.DragEventArgs) Handles CasesBox2.DragOver
Dim MousePoint As Windows.Point = e.GetPosition(Nothing)
End Sub
Private Sub CasesBox2_Drop(sender As Object, e As System.Windows.DragEventArgs) Handles CasesBox2.Drop
If e.Data.GetDataPresent("myFormat") Then
Dim contact As Details = TryCast(e.Data.GetData("myFormat"), Details)
Dim cse As Cases = CasesBox2.SelectedItem
If cse IsNot Nothing Then
Dim cs2 As ObservableCollection(Of Details) = DtlBox3.ItemsSource
cs2.Remove(contact)
cse.AddDetailsToCase(contact)
IsDragInitiated = False
End If
IsDragInitiated = False
End If
IsDragInitiated = False
End Sub
Private Sub CasesBox2_SelectionChanged(sender As Object, e As System.Windows.Controls.SelectionChangedEventArgs) Handles CasesBox2.SelectionChanged
Try
If IsDragInitiated Then
Else
Dim SelectedItem As Cases = CasesBox2.SelectedItem
DtlBox3.ItemsSource = SelectedItem.CaseDetails
End If
Catch ex As Exception
End Try
End Sub
Private Sub DtlBox3_MouseMove(sender As Object, e As System.Windows.Input.MouseEventArgs) Handles DtlBox3.MouseMove
Try
' Get the current mouse position
Dim mousePos As Windows.Point = e.GetPosition(Nothing)
Dim diff As Vector = StartPoint - mousePos
If e.LeftButton = MouseButtonState.Pressed AndAlso Math.Abs(diff.X) > SystemParameters.MinimumHorizontalDragDistance OrElse Math.Abs(diff.Y) > SystemParameters.MinimumVerticalDragDistance Then
' Get the dragged ListViewItem
Dim listView As ListBox = TryCast(sender, ListBox)
Dim listViewItem As ListBoxItem = FindAnchestor(Of ListBoxItem)(DirectCast(e.OriginalSource, DependencyObject))
' Find the data behind the ListViewItem
Dim contact As Details = DirectCast(listView.ItemContainerGenerator.ItemFromContainer(listViewItem), Details)
' Initialize the drag & drop operation
Dim dragData As New DataObject("myFormat", contact)
IsDragInitiated = True
DragDrop.DoDragDrop(listViewItem, dragData, DragDropEffects.Move)
End If
Catch ex As Exception
End Try
End Sub
' Helper to search up the VisualTree
Private Shared Function FindAnchestor(Of T As DependencyObject)(current As DependencyObject) As T
Do
If TypeOf current Is T Then
Return DirectCast(current, T)
End If
current = VisualTreeHelper.GetPa开发者_运维百科rent(current)
Loop While current IsNot Nothing
Return Nothing
End Function
Private Sub DtlBox3_PreviewMouseLeftButtonDown(sender As Object, e As System.Windows.Input.MouseButtonEventArgs) Handles DtlBox3.PreviewMouseLeftButtonDown
StartPoint = e.GetPosition(Nothing)
End Sub
Private Sub Border_MouseEnter(sender As System.Object, e As System.Windows.Input.MouseEventArgs)
CasesBox2.SelectedItem = CType(sender, Border).DataContext
If CasesBox2.IsFocused Then
Else
CasesBox2.Focus()
End If
End Sub
Sounds like you're trying to do hot-tracking with DragOver on individual list items.
If you're using WPF, you could probably make a custom template for ListBoxItems that has a trigger for that.
If not: You could implement DragOver on the list items themselves instead of just the ListBox control, and you would need to maintain a reference to the currently hot-tracked item so you could un-highlight it. This means your ListBox has to be populated with some custom objects, though.
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