How to prevent a TabItem from being selected?

Herry Markowitz

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There is no TabControl.Selecting Event in the WPF while there is in the Winform as you can see following.
https://msdn.microsoft.com/en-us/lib...v=vs.110).aspx


I have found following source in order to prevent a TabItem from being selected.
https://joshsmithonwpf.wordpress.com...eing-selected/

VB.NET:
[COLOR=#333333]public Window1()[/COLOR]{
     InitializeComponent();

     base.DataContext = new DataSource();

     var items = new string[] { "A", "B", "C" };
     this.tab.ItemsSource = items;
     var collView = CollectionViewSource.GetDefaultView(items);
     collView.CurrentChanging += this.OnTabItemSelecting;
}

void OnTabItemSelecting(object sender, CurrentChangingEventArgs e)
{
     bool allow = this.chk.IsChecked.GetValueOrDefault();
     if (!allow)
     {
          // SelectedContent hasn't changed yet, so use it to figure out
          // the index of the previously selected tab
          int prevIdx = this.tab.Items.IndexOf(this.tab.SelectedContent);
          this.tab.SelectedIndex = prevIdx;
     } [COLOR=#333333]}[/COLOR]

Converted code via http://converter.telerik.com/;

VB.NET:
[COLOR=#333333]Public Sub Window1()[/COLOR]    InitializeComponent()
    MyBase.DataContext = New DataSource()
    Dim items = New String() {"A", "B", "C"}
    Me.tab.ItemsSource = items
    Dim collView = CollectionViewSource.GetDefaultView(items)
    collView.CurrentChanging += AddressOf Me.OnTabItemSelecting
End Sub

Private Sub OnTabItemSelecting(ByVal sender As Object, ByVal e As CurrentChangingEventArgs)
    Dim allow As Boolean = Me.chk.IsChecked.GetValueOrDefault()
    If Not allow Then
        Dim prevIdx As Integer = Me.tab.Items.IndexOf(Me.tab.SelectedContent)
        Me.tab.SelectedIndex = prevIdx
    End If [COLOR=#333333]End Sub[/COLOR]

My XAML codes;

VB.NET:
[COLOR=#333333]<Window x:Class="MainWindow"[/COLOR]  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="TabControlSample" Height="200" Width="250">
    <Grid>
        <TabControl x:Name="tab">
            <TabItem Header="General">
                <Label Content="Content goes here..." />
            </TabItem>
            <TabItem Header="Security" />
            <TabItem Header="Details" />
        </TabControl>
    </Grid> [COLOR=#333333]</Window>[/COLOR]

Here is the error picture: https://prnt.sc/ijtvm4


To be honest I am not good at with constructors.

So I need you support.
 

JohnH

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The "+=" in C# adds to delegate list for event handler, in VB you use AddHandler Statement to add the event handler, like:
Addhandler collView.CurrentChanging, AddressOf Me.OnTabItemSelecting
 

Herry Markowitz

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Messages
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Programming Experience
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Hi JohnH.
I am very fresh in vb.net programming.
So, I need completed code which is ready to run.
So, please post whole code.
 

JohnH

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There's nothing more to post, that's how you add handler with vb.net instead of += in C#. I'm not looking at the other stuff, so if there are other issues you should ask specifically about them.
 

Herry Markowitz

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Hi jmcilhinney,


If you still interested in this issue I think you are going to help me
:love_heart:
 

jmcilhinney

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I have helped you. I've told you that you should download Instant VB to get the best possible conversion of C# code to VB but you seem determined not to do so. If it is your opinion that the only way I can help is to write your code for you then I'm afraid that you'll be disappointed.
 

Herry Markowitz

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Programming Experience
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You know what, one day I will come back here with correct code;) Wait me here ;)
 

Herry Markowitz

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Joined
Oct 22, 2015
Messages
46
Programming Experience
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Solved by myself.

VB.NET:
Class MainWindow
PublicSubNew()
        InitializeComponent()
        Me.tab.ItemsSource=NewString(){"A","B","C"}
        AddHandler tab.SelectionChanged,AddressOfOnTabItemSelecting
    EndSub
    PrivateSubOnTabItemSelecting(ByVal sender AsObject,ByVal e AsSelectionChangedEventArgs)
        Dim allow AsBoolean=Me.chk.IsChecked.GetValueOrDefault()
        IfNot allow Then
            Dim prevIdx AsInteger=Me.tab.Items.IndexOf(Me.tab.SelectedContent)
            Me.tab.SelectedIndex= prevIdx
        EndIf
    EndSub
EndClass
 
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