Change background for hover item in QFontComboBox?

legitnameyo

I want to change the background to a grey color of the item that the mouse hovers over in a QFontComboBox. I've tried with all of these styles but none works

    combo_box_fonts->setStyleSheet(QString("QFontComboBox {background-color: white; color: black; border: 0px solid white; border-radius: 3px;}"

"QFontComboBox QAbstractItemView {background-color: white; color: black;}"

"QFontComboBox QAbstractItemView::item:hover {background: #d9d9d9; color: black;}"

"QFontComboBox QListView::item:hover {background: #d9d9d9; color: black;}"

"QListView::item:hover {background: #d9d9d9; color: black;}"

"QFontComboBox QListView:hover {background: #d9d9d9; color: black;}

 "QFontComboBox::item:hover {background: #d9d9d9; color: black;}"

"QFontComboBox:on:hover {background: #d9d9d9; color: black;}"));

I've tried all of these styles by themselves and all of these styles together, but the background color of the hovered item is always red.

Edit: There is no error and every style I've applied have worked, besides :hover

mrjj

Hi
Using
ui->fontComboBox->dumpObjectTree();
we can see the object tree.

QFontComboBox::fontComboBox 
    QLineEdit:: 
        QWidgetLineControl:: 
        QCompleter:: 
            QCompletionModel:: 
    QComboBoxPrivateContainer:: 
        QBoxLayout:: 
        QComboBoxListView:: 
            QWidget::qt_scrollarea_viewport 
            QWidget::qt_scrollarea_hcontainer 
                QScrollBar:: 
                QBoxLayout:: 
            QWidget::qt_scrollarea_vcontainer 
                QScrollBar:: 
                QBoxLayout:: 
            QItemSelectionModel:: 
            QItemSelectionModel:: 
    QStringListModel:: 
    QFontFamilyDelegate::

We can see its a QComboBoxListView
and doing
QComboBoxListView {background: red}
does change its background
alt text

However, the items are drawn using a delegate (QFontFamilyDelegate) and it seems it does not care for ::hover setting.

legitnameyo

I tried styling it with

*:hover {color: red;}

No text turned red when I hovered. I guess that means that the background color of the item hovered is controlled by something else...

mrjj

@legitnameyo
Yes the Delegate draws the items.
https://code.woboq.org/qt5/qtbase/src/widgets/widgets/qfontcombobox.cpp.html#_ZNK19QFontFamilyDelegate5paintEP8QPainterRK20QStyleOptionViewItemRK11QModelIndex

legitnameyo

So my theory is, @mrjj, that I have to change the source code of where the item is changed and then build Qt from source, is that right? I've got no other alternative?

mrjj

@legitnameyo
well you also take the delegate code and reuse
that to make a version where it draws as you want.
(using option.state & QStyle::State_MouseOver ) to react to hover.
and set you delegate with ui->fontComboBox->setItemDelegate.

Update:
yep very possible.
alt text

.h file with the code
https://www.dropbox.com/s/9g85hpxyle0zq52/qfontfamilydelegate.h?dl=0
include that in project and do
ui->fontComboBox->setItemDelegate(new QFontFamilyDelegate(this));

Disclaimer, i used 5 mins on it. so the actual hover drawing needs more love.
It was just a check to verify it was indeed possible :)

legitnameyo

@mrjj your file works like a charm! Thanks for the help!