QTimer and PyQt

[Phil Thompson]

On Tuesday 20 July 2004 12:41 pm, Adrian Casey wrote:
> I'm using a QTimer object to expire certain password protected GUI options
> in my application after 2 minutes.  Currently, the timer is reset each time
> the user presses the 'OK' button.  This is not ideal.  A user may spend 2
> minutes entering data into the GUI before pressing OK in which case the
> timer expires before they have pressed OK.
>
> I want the timer to timeout after 2 minutes of keyboard inactivity (i.e. no
> events sent) instead of 2 minutes following the last 'OK' click.
>
> I can imagine 2 ways to do this -:
>
> 1.  Reset the timer (timer.stop(), timer.start()) each time a keystroke
> event is received
>   -- or --
> 2.  At timeout, check if any fields have changed (using the isChanged()
> method.) and if so, reset the timer.
>
> The problem is, I don't know how to do either in PyQt!  I think option 2
> would be more efficient.  Is it possible to check the parent widget for any
> changes to child widgets or do I have to iterate over each widget on the
> form, checking each indivually?

Note that these questions are Qt questions, not PyQt questions. You may get 
better answers from a Qt mailing list.

For 1., you can detect a keystroke by reimplementing an object's event() 
method. A better solution would be to sub-class from QTimer and use it as an 
event filter (see QObject.installEventFilter()) for all the fields you want 
to watch for keystrokes - then restart the timer when you see a relevant 
keystroke event.

For 2., you would have to iterate over each widget.

Check out the section "Events and Event Filters" in the Qt documentation.

Phil