C# application is blocked

[Guest]

Hi,

Under a Windows CE .NET 4.2 OS, I have a problem with a C# application which
is the following :
when I call often a routine, my application is blocked on the MessageBox and
I must do a reboot of the PDA.

The routine is the following :

---------------------------------------------------------------------
private void routine()
{
MessageBox.Show("Message", "Title");
textBox1.Text = "";
textBox1.Enabled = false;
textBox2.Enabled = true;
textBox2.Text = "";
textBox2.Focus();
}
-------------------------------------------------------
When I debug, I have no message, I can see where the program is blocking.
I think it's a problem between the MessageBox and the focus on "textBox2"
field ?

Thanks for any help.

 

[Ginny Caughey [MVP]]

If you comment out the textBox2.Focus() do you have the same problem?

 

[Chris Tacke [MVP]]

Is "routine" running in a separate thread or in an event handler (like for a
timer)?

-Chris

 

[Daniel Moth]

Like Chris is implying, chances are you are running that method on a worker
thread and hence should use Control.Invoke before touching UI elements:
http://www.danielmoth.com/Blog/2004/10/invoke-cf-and-full-fx.html

Cheers
Daniel

 

[Guest]

OK, thanks.
But what do you mean exactly, should I use this method after
"MessageBox.Show()" ? So "textBox2.Invoke()" in the sample of code I gave you
in the last post ?

Thanks in advance for any information.

 

[Daniel Moth]

If you read the link I sent and the links it points to you will get the
answer to the question you ask, gain a better understanding on why the
advice was given and also never face this problem again.

Whether you decide to Invoke from wherever you call that routine so the
whole method is on the UI thread or whether you decide to split the method
so the msgbox happens before Invoking is your decision which you will be
able to make once you follow the links.

Cheers
Daniel

 

[Guest]

The point is, what is calling "routine"? In what thread context is it
running? If it's not the UI thread, then calls to UI elements must go
through Invoke.

-Chris