QTabBar and dynamic setTabButton

Lachrymology

Hi all,

I have a problem with the following function: QTabBar::setTabButton

The function itself can receive a QWidget.

I've used my own derived QWidget, which contains two QPushButtons which have a fixed width.

Theses two buttons are changing their visibility during runtime.

My problem is, that the tab width doesn't adjust its size dynamically to the new width of the widget.
I tried to overwrite the sizeHint of the derived widget, which didn't had any effect. At least I used setFixedWidth for the widget. Furthermore I used QTabBar::repaint

The tab itself doesn't shrink or grow based on the new width of the widget - ONLY the text of the tab is moved based on the widget size.

If I resize the entire window for 1 pixel all tabs are receiving their correct size based on their widgets.

Does anyone have a clue how to force the QTabBar to paint the tabs like the entire window was resized?

Best regards,
Mike

Lachrymology

Hi all,

after a bit trial and error I discovered three dirty work-a-rounds.

I think the not executed "d->layoutTabs();" is responsible for this behaviour:

void QTabBar::resizeEvent(QResizeEvent *)
{
    Q_D(QTabBar);
    if (d->layoutDirty)
        updateGeometry();
    d->layoutTabs();

    d->makeVisible(d->currentIndex);
}

The first work-a-round is to resize the tabBar two times:

    this->tabBar()->resize(this->tabBar()->size() + QSize(1, 1));
    this->tabBar()->resize(this->tabBar()->size() - QSize(1, 1));

Another way would be to set the same icon size again to set the layoutDirty=true:

this->tabBar()->setIconSize( this->tabBar()->iconSize() );

The problem with this is, that the tabBar jumps to the beginning of the available tabs and doesn't stay at the selected tab.

The third and maybe best work-a-round is the following:

    if( this->count() > 0 )
        this->tabBar()->setTabText( 0, this->tabBar()->tabText( 0 ) );

Any other ideas are appreciated.

Best regards,
Mike

raven-worx

@Lachrymology
try:

QEvent e(QEvent::FontChange);
QCoreApplication::sendEvent( tabBar, &e );

Lachrymology

@raven-worx
Thanks for your work-a-round. It's quite simple and smooth.