How to control QListWidget height depending on the presence of horizontal scrollbar?

roni219

Hello,

I use QListWidget to preview the row of icons with text captions.

MyWidget::MyWidget() :
    QListWidget(0)
{
    setWrapping(false);
    setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);

    setViewMode(QListWidget::IconMode);
    setResizeMode(QListWidget::Adjust);
    
    int height = 76; // height of an item + height of scrollbar
    setFixedHeight(height);
}

The code sets fixed height for the entire widget. It looks good when the horizontal scrollbar is present:

https://drive.google.com/open?id=0B3VIzaAFexv9ODhmYmswbUlyXzA

When widget is resized to accommodate all items, scrollbar disappears (as expected). But the widget has extra white space below the items:

https://drive.google.com/open?id=0B3VIzaAFexv9bi1qdWFkYkJIams

Instead I would like to have a fixed viewport height. The entire widget height should change when the widget is resized. It must depend on the presence absence of toolbar as

Without toolbar: widget height == item height
With toolbar: widget height == item height + toolbar height

How can this be done?

Thank you in advance!

Roni.

kshegunov

Hi,
You can install an event filter to the scrollbar and capture the show/hide events and then in the event filter you can adjust your widget's size accordingly.

Kind regards.

roni219

Thank you for the prompt response, @kshegunov! I will try out your suggestion, and post the result.

VRonin

what you want is probably

setSizeAdjustPolicy(QAbstractScrollArea::AdjustToContents);
setSizePolicy(QSizePolicy::Maximum, QSizePolicy::Maximum);

instead of

int height = 76; // height of an item + height of scrollbar
setFixedHeight(height);

roni219

Thank you for the suggestion, @VRonin. I tried the fix. The widget shrunk horizontally, instead of taking the entire width allowed it in the layout:

https://drive.google.com/open?id=0B3VIzaAFexv9d3BnLTFJT0JfRmc

When toolbar was present the bottom part of the caption was obscured:

https://drive.google.com/open?id=0B3VIzaAFexv9VW16X2FDMDRLOGc

The first issue is fixed by using

setSizePolicy(QSizePolicy::Ignored, QSizePolicy::Maximum);

But the indexes are partially obscured by toolbar. Or almost entirely obscured in non-zero spacing is set to the widget.

roni219

Can anybody comment, please? To summarise, the QAbstractScrollArea::AdjustToContents method, proposed by @VRonin, is simple and almost works:

The hight adjusts to the icons, but not to the icons+text underneath them.

Is it possible to make it adjust so that both icons and text is visible?

Thanks!