From msa01 at bitflipper.ca  Wed Jan 10 07:44:07 2024
From: msa01 at bitflipper.ca (Cam Farnell)
Date: Wed, 10 Jan 2024 08:44:07 -0400
Subject: [Tkinter-discuss] Focus issue
In-Reply-To: <0BC70B5D93E054469872FFD0FE07220E033860E8C2@CERNXCHG53.cern.ch>
References: <0BC70B5D93E054469872FFD0FE07220E033860D835@CERNXCHG53.cern.ch>
 <0BC70B5D93E054469872FFD0FE07220E033860E8C2@CERNXCHG53.cern.ch>
Message-ID: <bb4a3852-9791-4889-a881-172fd52fea58@bitflipper.ca>

In a rather large program I have this code:

self.TextWidget.focus_set()
print("type(self.TextWidget)=%s"%type(self.TextWidget))
print('Focus_get()=%s'%self.focus_get())

The goal is to have TextWidget get the focus. Usually it does, but there is one particular circumstance when it does not get the focus. The "print" lines I added for debugging.

The output from the print functions is:

type(self.TextWidget)=<class 'rpWidgets.ColorizedText'>
Focus_get()=None

TextWidget is an instance of rpWidgets.ColorizedText which is created thus:

class ColorizedText(tkinter.Text):

which is to say, it's just a tkinter.Text to which I've added methods.

I've tried creating a minimum example without success.

My questions is: how is it possible for TextWidget to NOT have the focus immediately after a call to focus_set?

Changing focus_set to focus_force makes no difference.

Invoking update_idletasks() after the focus_set makes no difference.

The TextWidget in question is visible on the screen, and pressing Tab a couple of times does get it the focus.

Having spent some hours chasing this I'm a tad frustrated, but quite open to suggestions about what to look for.

Cheers

Cam Farnell




From msa01 at bitflipper.ca  Wed Jan 10 15:33:46 2024
From: msa01 at bitflipper.ca (Cam Farnell)
Date: Wed, 10 Jan 2024 16:33:46 -0400
Subject: [Tkinter-discuss] Focus issue
In-Reply-To: <bb4a3852-9791-4889-a881-172fd52fea58@bitflipper.ca>
References: <0BC70B5D93E054469872FFD0FE07220E033860D835@CERNXCHG53.cern.ch>
 <0BC70B5D93E054469872FFD0FE07220E033860E8C2@CERNXCHG53.cern.ch>
 <bb4a3852-9791-4889-a881-172fd52fea58@bitflipper.ca>
Message-ID: <c9b98955-346f-4562-bdcc-e6ed9ac6817e@bitflipper.ca>

To answer my own question: the focus was being given to another widget after the code in question had executed.

That said, I still don't understand why focus_set followed by update_idletasks followed by focus_get would return None, but tkinter something works in strange and mysterious ways.

Cheers

Cam

On 2024-01-10 08:44, Cam Farnell wrote:
> In a rather large program I have this code:
> 
> self.TextWidget.focus_set()
> print("type(self.TextWidget)=%s"%type(self.TextWidget))
> print('Focus_get()=%s'%self.focus_get())
> 
> The goal is to have TextWidget get the focus. Usually it does, but there is one particular circumstance when it does not get the focus. The "print" lines I added for debugging.
> 
> The output from the print functions is:
> 
> type(self.TextWidget)=<class 'rpWidgets.ColorizedText'>
> Focus_get()=None
> 
> TextWidget is an instance of rpWidgets.ColorizedText which is created thus:
> 
> class ColorizedText(tkinter.Text):
> 
> which is to say, it's just a tkinter.Text to which I've added methods.
> 
> I've tried creating a minimum example without success.
> 
> My questions is: how is it possible for TextWidget to NOT have the focus immediately after a call to focus_set?
> 
> Changing focus_set to focus_force makes no difference.
> 
> Invoking update_idletasks() after the focus_set makes no difference.
> 
> The TextWidget in question is visible on the screen, and pressing Tab a couple of times does get it the focus.
> 
> Having spent some hours chasing this I'm a tad frustrated, but quite open to suggestions about what to look for.
> 
> Cheers
> 
> Cam Farnell
> 
> 
> 
> _______________________________________________
> Tkinter-discuss mailing list
> Tkinter-discuss at python.org
> https://mail.python.org/mailman/listinfo/tkinter-discuss

From klappnase at web.de  Wed Jan 10 18:51:53 2024
From: klappnase at web.de (Michael Lange)
Date: Thu, 11 Jan 2024 00:51:53 +0100
Subject: [Tkinter-discuss] Focus issue
In-Reply-To: <c9b98955-346f-4562-bdcc-e6ed9ac6817e@bitflipper.ca>
References: <0BC70B5D93E054469872FFD0FE07220E033860D835@CERNXCHG53.cern.ch>
 <0BC70B5D93E054469872FFD0FE07220E033860E8C2@CERNXCHG53.cern.ch>
 <bb4a3852-9791-4889-a881-172fd52fea58@bitflipper.ca>
 <c9b98955-346f-4562-bdcc-e6ed9ac6817e@bitflipper.ca>
Message-ID: <20240111005153.6382076893c9204de13c6aef@web.de>

Hi,

On Wed, 10 Jan 2024 16:33:46 -0400
Cam Farnell <msa01 at bitflipper.ca> wrote:

> To answer my own question: the focus was being given to another widget
> after the code in question had executed.
>
> That said, I still don't understand why focus_set followed by
> update_idletasks followed by focus_get would return None, but tkinter
> something works in strange and mysterious ways.
>

I can only guess here, have you tried calling update_idletasks() (or even
update()) *before* calling focus_set() ?

Best regards,

Michael