QItemDelegate Class Reference
^{[QtGui module]}

Subclassing

When subclassing QItemDelegate to create a delegate that displays items using a custom renderer, it is important to ensure that the delegate can render items suitably for all the required states; e.g. selected, disabled, checked. The documentation for the paint() function contains some hints to show how this can be achieved.

See also Model/View Programming and QAbstractItemDelegate.

Member Function Documentation

QItemDelegate::QItemDelegate ( QObject * parent = 0 )

Constructs an item delegate with the given parent.

QItemDelegate::~QItemDelegate ()

Destroys the item delegate.

QWidget * QItemDelegate::createEditor ( QWidget * parent, const QStyleOptionViewItem & option, const QModelIndex & index ) const   [virtual]

Returns the widget used to edit the item specified by index for editing. The parent widget and style option are used to control how the editor widget appears.

Reimplemented from QAbstractItemDelegate.

See also QAbstractItemDelegate::createEditor().

void QItemDelegate::drawCheck ( QPainter * painter, const QStyleOptionViewItem & option, const QRect & rect, Qt::CheckState state ) const   [virtual protected]

Renders a check indicator within the rectangle specified by rect, using the given painter and style option, using the given state.

void QItemDelegate::drawDecoration ( QPainter * painter, const QStyleOptionViewItem & option, const QRect & rect, const QPixmap & pixmap ) const   [virtual protected]

Renders the decoration pixmap within the rectangle specified by rect using the given painter and style option.

void QItemDelegate::drawDisplay ( QPainter * painter, const QStyleOptionViewItem & option, const QRect & rect, const QString & text ) const   [virtual protected]

Renders the item view text within the rectangle specified by rect using the given painter and style option.

void QItemDelegate::drawFocus ( QPainter * painter, const QStyleOptionViewItem & option, const QRect & rect ) const   [virtual protected]

Renders the region within the rectangle specified by rect, indicating that it has the focus, using the given painter and style option.

bool QItemDelegate::eventFilter ( QObject * object, QEvent * event )   [virtual protected]

If the object is the current editor: if the event is an Esc key press the current edit is cancelled and ended, or if the event is an Enter or Return key press the current edit is accepted and ended. If editing is ended the event filter returns true to signify that it has handled the event; in all other cases it does nothing and returns false to signify that the event hasn't been handled.

Reimplemented from QObject.

See also closeEditor().

QItemEditorFactory * QItemDelegate::itemEditorFactory () const

Returns the editor factory used by the item delegate. If no editor factory is set, the function will return null.

See also setItemEditorFactory().

void QItemDelegate::paint ( QPainter * painter, const QStyleOptionViewItem & option, const QModelIndex & index ) const   [virtual]

Renders the delegate using the given painter and style option for the item specified by index.

When reimplementing this function in a subclass, you should update the area held by the option's rect variable, using the option's state variable to determine the state of the item to be displayed, and adjust the way it is painted accordingly.

For example, a selected item may need to be displayed differently to unselected items, as shown in the following code:

        if (option.state & QStyle::State_Selected)
            painter->setBrush(option.palette.highlight());
        else
        ...

After painting, you should ensure that the painter is returned to its the state it was supplied in when this function was called. For example, it may be useful to call QPainter::save() before painting and QPainter::restore() afterwards.

Reimplemented from QAbstractItemDelegate.

See also QStyle::State.

void QItemDelegate::setEditorData ( QWidget * editor, const QModelIndex & index ) const   [virtual]

Sets the data to be displayed and edited by the editor for the item specified by index.

Reimplemented from QAbstractItemDelegate.

void QItemDelegate::setItemEditorFactory ( QItemEditorFactory * factory )

Sets the editor factory to be used by the item delegate to be the factory specified. If no editor factory is set, the item delegate will use the default editor factory.

See also itemEditorFactory().

void QItemDelegate::setModelData ( QWidget * editor, QAbstractItemModel * model, const QModelIndex & index ) const   [virtual]

Sets the data for the specified model and item index from that supplied by the editor.

Reimplemented from QAbstractItemDelegate.

QSize QItemDelegate::sizeHint ( const QStyleOptionViewItem & option, const QModelIndex & index ) const   [virtual]

Returns the size needed by the delegate to display the item specified by index, taking into account the style information provided by option.

Reimplemented from QAbstractItemDelegate.

void QItemDelegate::updateEditorGeometry ( QWidget * editor, const QStyleOptionViewItem & option, const QModelIndex & index ) const   [virtual]

Updates the editor for the item specified by index according to the style option given.

Reimplemented from QAbstractItemDelegate.