Grouped QComboBox

Question

Could you show me a simple example of how to make this grouped combobox in Qt?

Answer 1

You can find the description how to do this here:

http://web.archive.org/web/20170826190441/mimec.org/node/305

The idea is that you add parent items and child items and then they are painted differently with the help of custom delegate.

I.e. you set

item->setData( "parent", Qt::AccessibleDescriptionRole );

when adding parent item of group and

item->setData( "child", Qt::AccessibleDescriptionRole );

otherwise.

And then you use this information for painting:

if ( type == QLatin1String( "parent" ) ) {
        QStyleOptionViewItem parentOption = option;
        parentOption.state |= QStyle::State_Enabled;
        QItemDelegate::paint( painter, parentOption, index );
    } 
    else if ( type == QLatin1String( "child" ) ) {
        QStyleOptionViewItem childOption = option;
        int indent = option.fontMetrics.width( QString( 4, QChar( ' ' ) ) );
        childOption.rect.adjust( indent, 0, 0, 0 );
        childOption.textElideMode = Qt::ElideNone;
        QItemDelegate::paint( painter, childOption, index );
    }