MessageBox doesn't take focus

Question

When I click enter-button, MessageBox is shown. I want MessageBox to close when I click enter-button again as usual. Problem is - it doesn't have focus, but TextBox has and when I click enter-button _textBox_OnKeyUp eventhandler is invoked again and again. How can I solve my problem?

Markup:

<Grid>
    <TextBox Name="_textBox"
        Width="100"
        Height="30"
        Background="OrangeRed"
        KeyUp="_textBox_OnKeyUp"/>
</Grid>

Code:

private void _textBox_OnKeyUp(object sender, KeyEventArgs e)
{
    if (e.Key != Key.Enter)
        return;

    MessageBox.Show("Bla-bla");
}

show this, I think, it is same with your case: http://stackoverflow.com/questions/6882196/wpf-command-for-textbox-which-fires-up-when-we-hit-enter-key-on-it — Mouaici_Med, Apr 06 '16 at 07:41
It is one of the infamous airspace issues, activation and focus needs to be emulated in WPF because controls are not windows. That can be quite glitchy if you don't do it the "normal" way, WPF has a hard-baked assumption that shortcut keystrokes are implemented with the KeyDown notification. Using that event instead trivially solves your problem. — Hans Passant, Apr 06 '16 at 09:02

Salah Akbari · Accepted Answer · 2016-04-06T09:45:03.093

3

You could use KeyDown event instead because the MessageBox responds to the KeyDown event:

<TextBox Name="_textBox"
         Width="100"
         Height="30"
         Background="OrangeRed"
         KeyDown="_textBox_OnKeyDown"/>

And:

private void _textBox_OnKeyDown(object sender, KeyEventArgs e)
{
    if (e.Key != Key.Enter)
       return;

    MessageBox.Show("Bla-bla");
}

edited Apr 06 '16 at 09:45

answered Apr 06 '16 at 07:34

Salah Akbari

39,330
10
79
109

Thx, it seems to work, but what can I do if I MUST use KeyUp event? – monstr Apr 06 '16 at 07:41

Jean-Charbel VANNIER · Answer 2 · 2016-04-06T08:09:55.670

1

I recomend using this method of Messagebox.

MessageBox.Show(Window, String)

Taken from the MSDN :

Displays a message box in front of the specified window. The message box displays a message and returns a result.

You can use this as the following :

MessageBox.Show(Application.Current.MainWindow, "I'm on top of teh window so I should get focus");

EDIT :

You should give back the focus to your main window before calling the MessageBox.

private void _textBox_OnKeyUp(object sender, KeyEventArgs e)
{
    if (e.Key != Key.Enter)
        return;

    //this.Focus() or at least YourWindow.Focus()
    MessageBox.Show("Bla-bla");
}

edited Apr 06 '16 at 08:09

answered Apr 06 '16 at 07:44

Jean-Charbel VANNIER

396
1
13

No this doesn't still close the `MessageBox` by clicking the enter button again as OP wanted. – Salah Akbari Apr 06 '16 at 07:49
Agree with Akbai and in real application (not in this test) I have Application.Current.MainWindow = null – monstr Apr 06 '16 at 07:56
I've made an edit, if your Application.Current.MainWindow is null then you should replace my commentary by something that gives you the current window – Jean-Charbel VANNIER Apr 06 '16 at 08:20
I just used 'this' since I'm already in the Form needed to be ontop MessageBox.Show(this, ....) – iYazee6 Oct 23 '22 at 12:31

MessageBox doesn't take focus

2 Answers2