Control.Focus() Behavior has changed (for the worse?) in .NET 1.1

  • Thread starter Thread starter Brian Swanson
  • Start date Start date
B

Brian Swanson

Hi,

We've been bitten by a change in behavior between .NET 1.0 and .NET 1.1.

Specifically: We determine in the Leave event what control to move to next.
E.g., We call textbox4.Focus() in the leave event of TextBox1.

In .NET 1.0 you would get 1 leave event when pressing the TAB key and **no
extra leave event** when calling .Focus() from within the already running
Leave event

What's different in .NET 1.1 is that if the control that I'm calling Focus
on (TextBox4) was not **already next** in the tab sequence from TextBox1, I
will get a SECOND, undesirable, extra Leave event on TextBox1. This has
broken our application and is causing a significant headache with our
migration to the new framework.

Is there a reason that this is happening, and is there a way for us to fix
this without undertaking a massive code change?

By the way, a similar reply to another thread provided by "Ying-Shen
Yu[MSFT]" suggested that putting focus() code inside of Focus events can
mess up the Windows message loop. I'm not sure if this example falls under
the same category. We've tried putting the call to Focus() on a call to
Control.Invoke (via the ThreadPool.QueueWorkItem) but this has two problems:

a) It defers execution of the Focus() event until after the Leave event has
finished executing
b) More seriously, it causes or allows the focus events of TextBox2 (the
next natural control in the tab sequence) to execute before finally
transferring control to the intended control (TextBox4).

Any thoughts or ideas????

Thanks!

Brian
 
b) More seriously, it causes or allows the focus events of TextBox2 (the
next natural control in the tab sequence) to execute before finally
transferring control to the intended control (TextBox4).

Any thoughts or ideas????
Click to expand...

Why not control the flow of tabbing with the TabIndex property and not
through code in the Leave event?
 
Well, I suppose that the issue is that there is not a "permanent" tab order
we know ahead of time that we can setup. We have a default tab order, but
the situation I'm in is that I need to override the tab order in some cases.
The next desired control in the sequence might vary based upon the result of
what was input into the current control.

What we would be looking for is a way to dynamically transfer focus to
varying controls based on user input. So, sometimes we might want to move to
TextBox4, others TextBox9. Oh well....

Thanks,

Brian
 
Well, I suppose that the issue is that there is not a "permanent" tab order
we know ahead of time that we can setup. We have a default tab order, but
the situation I'm in is that I need to override the tab order in some cases.
The next desired control in the sequence might vary based upon the result of
what was input into the current control.
Click to expand...

Hmmm... Could you disable the control that is next in the tab order?
Sort of "forcing" the focus to move to the next control?
 
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