Delegate editor shows double text while editing

pitonyak

I have a table view, and I created my own QStyledItemDelegate.

When I double click in a field that creates a text edit field, two sets of text are shown; the original and the new text that you are editing. The top portion of this image is how the Table looks before I double click in the cell to edit it. The bottom example shows the strange display.

!http://www.pitonyak.org/QT_Bad_Delegate.png(Double Text)!

Note that this used to work, and now it has this strange behavior. Sadly, I don't use this particular dialog often, so i am uncertain when it began. It may have been introduced with QT 5.0, and it may be related to my move from Fedora 17 to Fedora 18.

This is how I define my delegate

@class LinkBackFilterDelegate : public QStyledItemDelegate
{
Q_OBJECT
public:
explicit LinkBackFilterDelegate(QObject *parent = 0);

/*! \brief Returns the widget used to edit the item specified by index for editing.

\param [in, out] parent Used to control how the editor widget appears.
\param [in] option Used to control how the editor widget appears.
\param [in] index Indicates which column is of interest.
\return Widget used to edit the specified data (so the editor is specific to the column).
*/
QWidget *createEditor(QWidget *parent, const QStyleOptionViewItem &option,
const QModelIndex &index) const;

/*! \brief Set the data into the editor for the location based on the mode.
 *  The data is obtained from the model.
 */
void setEditorData(QWidget *editor, const QModelIndex &index) const;
void setModelData(QWidget *editor, QAbstractItemModel *model,
                  const QModelIndex &index) const;

void updateEditorGeometry(QWidget *editor,
    const QStyleOptionViewItem &option, const QModelIndex &index) const;

signals:

public slots:

};
@

This is how I created my QLineEdit that causes the problem

@QWidget *LinkBackFilterDelegate::createEditor(QWidget parent, const QStyleOptionViewItem &,
const QModelIndex &index) const
{
QVariant qvar = index.model()->data(index, Qt::EditRole);
if (qvar.type() == QVariant::StringList)
{
return new QComboBox(parent);
}
else if (qvar.type() == QVariant::Bool)
{
QCheckBox checkBox = new QCheckBox(parent);
checkBox->setTristate(false);
return checkBox;
}
return new QLineEdit(parent);
}@

Any thoughts?

pitonyak

Side note, I originally used QItemDelegate, and have gone back to it since I was not styling anything!.

pitonyak

One final comment. I am able to avoid the problem using something like this, but it just feels wrong.

@void LinkBackFilterDelegate::paint(QPainter * painter, const QStyleOptionViewItem & option, const QModelIndex & index) const
{
// This feels wrong, I should not need to do this, but, it works.
// If I do not do this, then the underlying text box shows through to the
// Editing text box.
if ((current_state & (QStyle::State_Active | QStyle::State_HasFocus | QStyle::State_Selected)) == QStyle::State_Selected) {
QItemDelegate::drawBackground( painter, option, index );
} else {
QItemDelegate::paint( painter, option, index );
}
}@

pitonyak

No ideas? Well, here is the solution I finally settled on (since relying on the state will fail in some rare situations.... well, not that rare).

@ //widget = new QLineEdit(parent);
// Returns an expanding line editor.
QWidget* widget = QStyledItemDelegate::createEditor(parent, option, index);

// If I do not set this to true, then the "view" data shows through the text while editing.
// Also, the expanding editor grows over existing controls, and you can see those through
// the edit display as well (distracting).
widget->setAutoFillBackground(true);
return widget;@