Question

I have successfully created a QListWidget that displays 2 lines of text for each item using this code (adapted from this example):

SessionListDelegate.h

#ifndef SESSIONLISTDELEGATE_H_
#define SESSIONLISTDELEGATE_H_

#include <QPainter>
#include <QAbstractItemDelegate>

class SessionListDelegate : public QAbstractItemDelegate
{
public:
    SessionListDelegate(QObject *parent = 0, QStyle *style);
    virtual ~SessionListDelegate();

    void paint (QPainter * painter, const QStyleOptionViewItem & option, const QModelIndex & index) const;
    QSize sizeHint (const QStyleOptionViewItem & option, const QModelIndex & index) const;
private:
};

#endif /* SESSIONLISTDELEGATE_H_ */

SessionListDelegate.cpp

#include "SessionListDelegate.h"

SessionListDelegate::SessionListDelegate(QObject *parent)
: QAbstractItemDelegate(parent)
{
    this->_parent = parent;
}

void SessionListDelegate::paint(QPainter * painter, const QStyleOptionViewItem & option, const QModelIndex & index) const
{
    QRect r = option.rect;

    QPen fontPen(QColor::fromRgb(51,51,51), 1, Qt::SolidLine);

    if(option.state & QStyle::State_Selected)
    {
        painter->fillRect(option.rect, option.palette.color(QPalette::Highlight));
    }
    painter->setPen(fontPen);

    QString date = index.data(Qt::DisplayRole).toString();
    QString description = index.data(Qt::UserRole).toString();

    int imageSpace = 10;

    r = option.rect.adjusted(imageSpace, 0, -10, -30);
    painter->setFont(QFont( "Lucida Grande", 24, QFont::Normal));
    painter->drawText(r.left(), r.top(), r.width(), r.height(), Qt::AlignBottom|Qt::AlignLeft, date, &r);

    r = option.rect.adjusted(imageSpace, 30, -10, 0);
    painter->setFont(QFont( "Lucida Grande", 18, QFont::Normal));
    painter->drawText(r.left(), r.top(), r.width(), r.height(), Qt::AlignLeft, description, &r);

}

QSize SessionListDelegate::sizeHint(const QStyleOptionViewItem & option, const QModelIndex & index) const
{
   return QSize(200, 60); // very dumb value
}

SessionListDelegate::~SessionListDelegate()
{
    // TODO Auto-generated destructor stub
}

Calling code in mainapp.cpp:

ui.myList->setItemDelegate(new SessionListDelegate(ui.myList));

Now, in the main QWidget form of my application UI, I have defined a style sheet which contains a style for all QListViews for the form:

QListView::item:selected {
color: black;
background-color: qlineargradient(spread:pad, x1:0, y1:1, x2:0, y2:0, stop:0 rgba(255, 255, 80, 255), stop:1 rgba(255, 255, 255, 255));
}

I would like to apply this style to the customized ListWidget, but I can’t think of a way to make that happen. It seems like it should be a pretty common thing to do, but I can’t find any examples anywhere.

Answer 1

I think you should inherit from QStyledItemDelegate instead of QAbstractItemDelegate. From the Qt documentation:

Since Qt 4.4, there are two delegate classes: QItemDelegate and
QStyledItemDelegate. However, the default delegate is
QStyledItemDelegate. These two classes are independent alternatives to
painting and providing editors for items in views. The difference
between them is that QStyledItemDelegate uses the current style to
paint its items. We therefore recommend using QStyledItemDelegate as
the base class when implementing custom delegates or when working with
Qt style sheet