setDefaultShortcutContext in KActionCollection

[Robin Stocker]

Andreas Hartmetz schrieb:
> On Wednesday 25 July 2007 21:48:52 Robin Stocker wrote:
> 
>>> Can you give a usage example?
>> Ah, sure. I wanted to fix a bug in Konsole for KDE 4, where the
>> shortcuts (Ctrl+Shift+N, etc) didn't work when the menu bar was hidden.
>> This is because the shortcuts are for actions which are added to the
>> menu and when the menu is hidden it doesn't get events and so the
>> shortcuts don't work anymore (this behaviour changed from Qt 3 to Qt 4,
>> I have tested it with minimal examples).
>>
>> The solution is to add the actions not only to the menu, but also to the
>> main window. Then I thought, well, why not use the setAssociatedWidget
>> method of KActionCollection? But this doesn't work because of the second
>> line in addAction in kactioncollection.cpp (line 238):
>>
>>     if (d->associatedWidgets.count()) {
>>         action->setShortcutContext(Qt::WidgetShortcut);
>>
>>         foreach (QWidget* w, d->associatedWidgets)
>>             w->addAction(action);
>>
>>     }
>>
>> The shortcut context is set from the default Qt::WindowShortcut to
>> Qt::WidgetShortcut, which means that the main window would have to have
>> direct focus, but that's never the case.
>>
>> Now, I don't understand why the shortcut context is set to
>> Qt::WidgetShortcut in the first place. Do you know why this could be
>> necessary? If we could remove this line, there would be no need for
>> setDefaultShortcutContext anymore, because the default of QAction is
>> Qt::WindowShortcut, which is fine. Also, it would be less surprising
>> that the shortcut context is changed in a addAction method.
>>
> Yes!
> 
>> The other solution is to add setDefaultShortcutContext again, but it
>> would be more code in both kactioncollection.cpp and the client code.
>>
> Would be nice to avoid this.
> 
>> I hope this makes the problem clear. Here's my original mail with the
>> patch which describes the problem and the solutions in greater detail:
>>
>> http://lists.kde.org/?l=konsole-devel&m=118529209602516&w=2
>>
>> Thank you for looking into this,
>>   Robin
> 
> Phew, and I thought that we'd have to reintroduce the old functions...
> KActionCollection::setAssociatedWidget() is new in KDE 4, so nobody should be 
> depending on the "bug"... I hope.
> Removing the line *now* might break something, but IMO it's much better to 
> break applications now when everything is somewhat broken. Suprising behavior 
> can bite application developers even long after release.
> So, without further ado, I'm going to commit this change.

Perfect. I hope a suitable solution can be found if it happens that
other applications break because of this change.

  Robin