Is it possible to rearrange tab items in tab control in wpf? - wpf

Question

Is it possible to rearrange tab items in tab control in run time? For example I have 3 tab items which are about cars and 4 tabs about house. I want to be able to rearrange them using drag and drop. Is it possible or it is something fantastic?
I have Tab Control here is XAML.
<TabControl x:Name="tc" Visibility="Collapsed" GotFocus="Focus" AllowDrop="True" >
</TabControl>
Tab items will be added in runtime.
Thanks for helping me!

Answer 1

found a solution in the MSDN forum.
Here is the link:
DragDrop TabItem
Here is the solution:
C# solution
WPF code:
<TabControl>
<TabControl.Resources>
<Style TargetType="TabItem">
<Setter Property="AllowDrop" Value="True"/>
<EventSetter Event="PreviewMouseMove" Handler="TabItem_PreviewMouseMove"/>
<EventSetter Event="Drop" Handler="TabItem_Drop"/>
</Style>
</TabControl.Resources>
<TabItem Header="Tabitem 1"/>
<TabItem Header="Tabitem 2"/>
<TabItem Header="Tabitem 3"/>
<TabItem Header="Tabitem 4"/>
<TabItem Header="Tabitem 5"/>
</TabControl>
C# code behind:
private void TabItem_PreviewMouseMove(object sender, MouseEventArgs e)
{
if (!(e.Source is TabItem tabItem))
{
return;
}
if (Mouse.PrimaryDevice.LeftButton == MouseButtonState.Pressed)
{
DragDrop.DoDragDrop(tabItem, tabItem, DragDropEffects.All);
}
}
private void TabItem_Drop(object sender, DragEventArgs e)
{
if (e.Source is TabItem tabItemTarget &&
e.Data.GetData(typeof(TabItem)) is TabItem tabItemSource &&
!tabItemTarget.Equals(tabItemSource) &&
tabItemTarget.Parent is TabControl tabControl)
{
int targetIndex = tabControl.Items.IndexOf(tabItemTarget);
tabControl.Items.Remove(tabItemSource);
tabControl.Items.Insert(targetIndex, tabItemSource);
tabItemSource.IsSelected = true;
}
}

Answer 2

When I tried to implement this solution, the drop event was firing twice (moving the tabs but them immediately moving them back). I had to add an integer to keep track of the last tab target index. My solution is in VB.NET
'additional variable
Dim lastTabTargetIndex As Integer = Nothing
Private Sub tc1_PreviewMouseMove(sender As Object, e As MouseEventArgs) Handles tc1.PreviewMouseMove
Dim Tabi = TryCast(e.Source, TabItem)
If Tabi Is Nothing Then
Exit Sub
Else
If Mouse.PrimaryDevice.LeftButton = MouseButtonState.Pressed Then
DragDrop.DoDragDrop(Tabi, Tabi, DragDropEffects.All)
End If
End If
End Sub
Private Sub tc1_Drop(sender As Object, e As DragEventArgs) Handles tc1.Drop
Dim tabItemTarget = TryCast(e.Source, TabItem)
Dim tabItemSource = TryCast(e.Data.GetData(GetType(TabItem)), TabItem)
If Not tabItemTarget.Equals(tabItemSource) Then
Dim tabControl = TryCast(tabItemTarget.Parent, TabControl)
Dim sourceIndex As Integer = tabControl.Items.IndexOf(tabItemSource)
Dim targetIndex As Integer = tabControl.Items.IndexOf(tabItemTarget)
'had to use this extra statement
If sourceIndex <> lastTabTargetIndex Then
'assign lastTabTargetIndex here
lastTabTargetIndex = targetIndex
tabControl.Items.Remove(tabItemSource)
tabControl.Items.Insert(targetIndex, tabItemSource)
tabControl.Items.Remove(tabItemTarget)
tabControl.Items.Insert(sourceIndex, tabItemTarget)
End If
End If
End Sub