strange behaviour with Qt::key_space

[franco.amato]

Hi,
I already posted this thread in the programming section and get no replies.
I hope ho have more luck here.
I'm implementing my:

void myWidget::keyPressEvent( QKeyEvent* pe )
{
    ..code ..
}

void myWidget::keyPressEvent( QKeyEvent* pe )
{
    ..code ..
}

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where I catch some keys. I have a problem with the space. I would run a routine when I press the space key so:

// start/stop
case Qt::Key_Space:
{
 qDebug() << "WaveWidget::keyPressEvent";
 bool playing;
 m_wave->getCurrentChannel()->isPlaying( &playing );
 if( playing == false )
    playSound(); 
 else
   StopSound(); 
 break;
}

// start/stop
case Qt::Key_Space:
{
 qDebug() << "WaveWidget::keyPressEvent";
 bool playing;
 m_wave->getCurrentChannel()->isPlaying( &playing );
 if( playing == false )
    playSound(); 
 else
   StopSound(); 
 break;
}

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It simply doesn't work. If I change Key_Space with another key I have no problems.
Which can be the problem?

Regards

[wysota]

So what exactly is the "strange behaviour"? You do know that the space key has a special meaning for dialogs and may be intercepted higher in the event processing chain, right?

[franco.amato]

So what exactly is the "strange behaviour"? You do know that the space key has a special meaning for dialogs and may be intercepted higher in the event processing chain, right?

Wysota the "strange behaviour" is that "nothing happens".
So I can not use the space?

[JD2000]

No, you can catch the space bar events, just make sure that the myWidget constructor gives the widget strong focus:

myWidget::myWidget(QWidget *parent)
{
setFocusPolicy(Qt::StrongFocus);
...
}

myWidget::myWidget(QWidget *parent)
{
setFocusPolicy(Qt::StrongFocus);
...
}

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You may also need to call QKeyEvent::accept() but this should not be necessary.

[franco.amato]

No, you can catch the space bar events, just make sure that the myWidget constructor gives the widget strong focus:

myWidget::myWidget(QWidget *parent)
{
setFocusPolicy(Qt::StrongFocus);
...
}

myWidget::myWidget(QWidget *parent)
{
setFocusPolicy(Qt::StrongFocus);
...
}

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You may also need to call QKeyEvent::accept() but this should not be necessary.

Hi I already set the focul policy to strongfocus but nothing change.
Seems the event is cached in another place

[wysota]

Wysota the "strange behaviour" is that "nothing happens".

Well... "nothing happens" is the default behaviour so I don't see anything strange in it

So I can not use the space?

Sure you can. Reimplement QObject::event() for your class or don't derive from QDialog and remember to give your widget (just make sure it's the right one) some sane focus policy.

[franco.amato]

Well... "nothing happens" is the default behaviour so I don't see anything strange in it

:-) OK

Sure you can. Reimplement QObject::event() for your class or don't derive from QDialog and remember to give your widget (just make sure it's the right one) some sane focus policy.

Hi my class derive from QWidget and I set

setFocusPolicy( Qt::StrongFocus );

setFocusPolicy( Qt::StrongFocus );

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as focus policy.
Can you explain me better what I have to reimplement?

[nish]

as suggested earlier, reimplement event() or eventFilter().

[wagmare]

use like this

bool cmylass:: eventFilter(QObject *ob, QEvent *e)
{
        if(ob == logout && e->type() == QEvent::KeyPress) {
                const QKeyEvent *ke = static_cast<QKeyEvent *>(e);
                if(ke->key()==)Qt::Key_Space{
                        //do your coding std ..
                }
                return true;
        }
         return QWidget::eventFilter(ob, e);
}

bool cmylass:: eventFilter(QObject *ob, QEvent *e)
{
        if(ob == logout && e->type() == QEvent::KeyPress) {
                const QKeyEvent *ke = static_cast<QKeyEvent *>(e);
                if(ke->key()==)Qt::Key_Space{
                        //do your coding std ..
                }
                return true;
        }
         return QWidget::eventFilter(ob, e);
}

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