QLabel as an item delegate

[qlands]

Hi,

I need to create an item delegate that shows the item data using a QLabel instead than a QEdit (the standard delegator for text data). The label need to show text (item value for example) in underline and blue and also show a different mouse pointer. See this image for example:



I can create a label that is blue, underline and has a different mouse pointer... But what do I need to do to use it in the delegate? I tried to follow the starDelegate example but I got lost in the paint().

Thanks for the help.

Carlos.

[wysota]

There is no such thing as "QEdit". The standard delegate draws everything by itself. If you want to use QLabel then you can use QAbstractItemView::setIndexWidget() but it is not advised since it has nothing to do with your model. It's better to implement a proper delegate, draw the text using QPainter::drawText() and handle events for cursor changes.

[qlands]

ok.

How can I handle the event for cursor changes? In the mouseEnter(), mouseLeave() of the delegator()?

Thanks.

[wysota]

In editorEvent()

[qlands]

Brilliant!

I guess I also need to reimplement sizeHint() ... How can I produce a value to return?

Maybe by giving the size of a normal QLabel holding the value:

QSize labelDelegate::sizeHint(const QStyleOptionViewItem &option,
               const QModelIndex &index) const
{
    QLabel tlabel;
    tlabel.setText(index.data().toString());
    return tlabel.size();
}

QSize labelDelegate::sizeHint(const QStyleOptionViewItem &option,
               const QModelIndex &index) const
{
    QLabel tlabel;
    tlabel.setText(index.data().toString());
    return tlabel.size();
}

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[wysota]

QFontMetrics

[qlands]

Yep.

I got that working after all.

Now the problem that I have is with the events enter and leave. Because editorEvent does not seem to receive such events from the view..

Here is the post:
http://www.qtcentre.org/threads/4383...er-leave-event

Thanks in advance.
Carlos.

[wysota]

Mouse tracking needs to be enabled for the view's viewport to receive such events, if I remember correctly.

[qlands]

Yes, I did enabled, thus I get mouse move but not enter/leave

[wysota]

Show your code.

[qlands]

Here is is:

labeldelegate.h

class labelDelegate : public QStyledItemDelegate
{
    Q_OBJECT
public:
    ...
    bool editorEvent(QEvent *event, QAbstractItemModel *model, const QStyleOptionViewItem &option, const QModelIndex &index);
 
...
 
};

class labelDelegate : public QStyledItemDelegate
{
    Q_OBJECT
public:
    ...
    bool editorEvent(QEvent *event, QAbstractItemModel *model, const QStyleOptionViewItem &option, const QModelIndex &index);
 
...

};

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labeldelegate.cpp

bool labelDelegate::editorEvent(QEvent *event, QAbstractItemModel *model, const QStyleOptionViewItem &, const QModelIndex &index)
{
    if (event->type() == QEvent::MouseButtonDblClick)
    {
       qDebug() << "TMouseButtonDblClick works fine";
 
        return true;
    }
    if (event->type() == QEvent::Enter) //Does not work
    {
        qDebug() << "Enter";
        QCursor cursor(Qt::PointingHandCursor);
        QApplication::setOverrideCursor(cursor);
        return true;
    }
    if (event->type() == QEvent::Leave)  //Does not work.
    {
        qDebug() << "Leave";
        QCursor cursor(Qt::ArrowCursor);
        QApplication::setOverrideCursor(cursor);
        return true;
    }
    return false;
}

bool labelDelegate::editorEvent(QEvent *event, QAbstractItemModel *model, const QStyleOptionViewItem &, const QModelIndex &index)
{
    if (event->type() == QEvent::MouseButtonDblClick)
    {
       qDebug() << "TMouseButtonDblClick works fine";
        
        return true;
    }
    if (event->type() == QEvent::Enter) //Does not work
    {
        qDebug() << "Enter";
        QCursor cursor(Qt::PointingHandCursor);
        QApplication::setOverrideCursor(cursor);
        return true;
    }
    if (event->type() == QEvent::Leave)  //Does not work.
    {
        qDebug() << "Leave";
        QCursor cursor(Qt::ArrowCursor);
        QApplication::setOverrideCursor(cursor);
        return true;
    }
    return false;
}

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Many thanks

[cplus]

You may use QTableWidget and use setCellWidget to set a widget to cells of QTableWidget.

[qlands]

Hi,

As it is discussed before setCellWidget is not advised since it has nothing to do with the model.

Carlos.

[wysota]

Since the editorEvent() for the events you want is not called, providing code for editorEvent() is pointless Try providing a minimal compilable example reproducing the problem. The most interesting part is how you prepare the view widget.