Qt 4.8: QListWidgetItem Class Reference

Qt Reference Documentation

# QListWidgetItem Class Reference

The QListWidgetItem class provides an item for use with the QListWidget item view class. More...

     #include <QListWidgetItem>

- List of all members, including inherited members
- Obsolete members

## Public Types

enum | ItemType { Type, UserType }

## Public Functions

| QListWidgetItem ( QListWidget * parent = 0, int type = Type )
| QListWidgetItem ( const QString & text, QListWidget * parent = 0, int type = Type )
| QListWidgetItem ( const QIcon & icon, const QString & text, QListWidget * parent = 0, int type = Type )
| QListWidgetItem ( const QListWidgetItem & other )
virtual | ~QListWidgetItem ()
QBrush | background () const
Qt::CheckState | checkState () const
virtual QListWidgetItem * | clone () const
virtual QVariant | data ( int role ) const
Qt::ItemFlags | flags () const
QFont | font () const
QBrush | foreground () const
QIcon | icon () const
bool | isHidden () const
bool | isSelected () const
QListWidget * | listWidget () const
virtual void | read ( QDataStream & in )
void | setBackground ( const QBrush & brush )
void | setCheckState ( Qt::CheckState state )
virtual void | setData ( int role, const QVariant & value )
void | setFlags ( Qt::ItemFlags flags )
void | setFont ( const QFont & font )
void | setForeground ( const QBrush & brush )
void | setHidden ( bool hide )
void | setIcon ( const QIcon & icon )
void | setSelected ( bool select )
void | setSizeHint ( const QSize & size )
void | setStatusTip ( const QString & statusTip )
void | setText ( const QString & text )
void | setTextAlignment ( int alignment )
void | setToolTip ( const QString & toolTip )
void | setWhatsThis ( const QString & whatsThis )
QSize | sizeHint () const
QString | statusTip () const
QString | text () const
int | textAlignment () const
QString | toolTip () const
int | type () const
QString | whatsThis () const
virtual void | write ( QDataStream & out ) const
virtual bool | operator< ( const QListWidgetItem & other ) const
QListWidgetItem & | operator= ( const QListWidgetItem & other )

## Related Non-Members

QDataStream & | operator<< ( QDataStream & out, const QListWidgetItem & item )
QDataStream & | operator>> ( QDataStream & in, QListWidgetItem & item )

## Detailed Description

The QListWidgetItem class provides an item for use with the QListWidget item view class.

A QListWidgetItem represents a single item in a QListWidget. Each item can hold several pieces of information, and will display them appropriately.

The item view convenience classes use a classic item-based interface rather than a pure model/view approach. For a more flexible list view widget, consider using the QListView class with a standard model.

List items can be inserted automatically into a list, when they are constructed, by specifying the list widget:

         new QListWidgetItem(tr("Hazel"), listWidget);

Alternatively, list items can also be created without a parent widget, and later inserted into a list using QListWidget::insertItem().

List items are typically used to display text() and an icon(). These are set with the setText() and setIcon() functions. The appearance of the text can be customized with setFont(), setForeground(), and setBackground(). Text in list items can be aligned using the setTextAlignment() function. Tooltips, status tips and "What's This?" help can be added to list items with setToolTip(), setStatusTip(), and setWhatsThis().

By default, items are enabled, selectable, checkable, and can be the source of drag and drop operations.

Each item's flags can be changed by calling setFlags() with the appropriate value (see Qt::ItemFlags). Checkable items can be checked, unchecked and partially checked with the setCheckState() function. The corresponding checkState() function indicates the item's current check state.

The isHidden() function can be used to determine whether the item is hidden. To hide an item, use setHidden().

### Subclassing

When subclassing QListWidgetItem to provide custom items, it is possible to define new types for them enabling them to be distinguished from standard items. For subclasses that require this feature, ensure that you call the base class constructor with a new type value equal to or greater than UserType, within your constructor.

See also QListWidget, Model/View Programming, QTreeWidgetItem, and QTableWidgetItem.

## Member Type Documentation

### enum QListWidgetItem::ItemType

This enum describes the types that are used to describe list widget items.

Constant | Value | Description
--- | --- | ---
`QListWidgetItem::Type` | `0` | The default type for list widget items.
`QListWidgetItem::UserType` | `1000` | The minimum value for custom types. Values below UserType are reserved by Qt.

You can define new user types in QListWidgetItem subclasses to ensure that custom items are treated specially.

See also type().

## Member Function Documentation

### QListWidgetItem::QListWidgetItem ( QListWidget * parent = 0, int type = Type )

Constructs an empty list widget item of the specified type with the given parent. If parent is not specified, the item will need to be inserted into a list widget with QListWidget::insertItem().

This constructor inserts the item into the model of the parent that is passed to the constructor. If the model is sorted then the behavior of the insert is undetermined since the model will call the `'<'` operator method on the item which, at this point, is not yet constructed. To avoid the undetermined behavior, we recommend not to specify the parent and use QListWidget::insertItem() instead.

See also type().

### QListWidgetItem::QListWidgetItem ( const QString & text, QListWidget * parent = 0, int type = Type )

Constructs an empty list widget item of the specified type with the given text and parent. If the parent is not specified, the item will need to be inserted into a list widget with QListWidget::insertItem().

This constructor inserts the item into the model of the parent that is passed to the constructor. If the model is sorted then the behavior of the insert is undetermined since the model will call the `'<'` operator method on the item which, at this point, is not yet constructed. To avoid the undetermined behavior, we recommend not to specify the parent and use QListWidget::insertItem() instead.

See also type().

### QListWidgetItem::QListWidgetItem ( const QIcon & icon, const QString & text, QListWidget * parent = 0, int type = Type )

Constructs an empty list widget item of the specified type with the given icon, text and parent. If the parent is not specified, the item will need to be inserted into a list widget with QListWidget::insertItem().

This constructor inserts the item into the model of the parent that is passed to the constructor. If the model is sorted then the behavior of the insert is undetermined since the model will call the `'<'` operator method on the item which, at this point, is not yet constructed. To avoid the undetermined behavior, we recommend not to specify the parent and use QListWidget::insertItem() instead.

See also type().

### QListWidgetItem::QListWidgetItem ( const QListWidgetItem & other )

Constructs a copy of other. Note that type() and listWidget() are not copied.

This function is useful when reimplementing clone().

This function was introduced in Qt 4.1.

See also data() and flags().

### QListWidgetItem::~QListWidgetItem ()`[virtual]`

Destroys the list item.

### QBrush QListWidgetItem::background () const

Returns the brush used to display the list item's background.

This function was introduced in Qt 4.2.

See also setBackground() and foreground().

### Qt::CheckState QListWidgetItem::checkState () const

Returns the checked state of the list item (see Qt::CheckState).

See also setCheckState() and flags().

### QListWidgetItem * QListWidgetItem::clone () const`[virtual]`

Creates an exact copy of the item.

### QVariant QListWidgetItem::data ( int role ) const`[virtual]`

Returns the item's data for a given role. Reimplement this function if you need extra roles or special behavior for certain roles.

See also Qt::ItemDataRole and setData().

### Qt::ItemFlags QListWidgetItem::flags () const

Returns the item flags for this item (see Qt::ItemFlags).

See also setFlags().

### QFont QListWidgetItem::font () const

Returns the font used to display this list item's text.

See also setFont().

### QBrush QListWidgetItem::foreground () const

Returns the brush used to display the list item's foreground (e.g. text).

This function was introduced in Qt 4.2.

See also setForeground() and background().

### QIcon QListWidgetItem::icon () const

Returns the list item's icon.

See also setIcon() and iconSize.

### bool QListWidgetItem::isHidden () const

Returns true if the item is hidden; otherwise returns false.

This function was introduced in Qt 4.2.

See also setHidden().

### bool QListWidgetItem::isSelected () const

Returns true if the item is selected; otherwise returns false.

This function was introduced in Qt 4.2.

See also setSelected().

### QListWidget * QListWidgetItem::listWidget () const

Returns the list widget containing the item.

### void QListWidgetItem::read ( QDataStream & in )`[virtual]`

Reads the item from stream in.

See also write().

### void QListWidgetItem::setBackground ( const QBrush & brush )

Sets the background brush of the list item to the given brush.

This function was introduced in Qt 4.2.

See also background() and setForeground().

### void QListWidgetItem::setCheckState ( Qt::CheckState state )

Sets the check state of the list item to state.

See also checkState().

### void QListWidgetItem::setData ( int role, const QVariant & value )`[virtual]`

Sets the data for a given role to the given value. Reimplement this function if you need extra roles or special behavior for certain roles.

See also Qt::ItemDataRole and data().

### void QListWidgetItem::setFlags ( Qt::ItemFlags flags )

Sets the item flags for the list item to flags.

See also flags() and Qt::ItemFlags.

### void QListWidgetItem::setFont ( const QFont & font )

Sets the font used when painting the item to the given font.

See also font().

### void QListWidgetItem::setForeground ( const QBrush & brush )

Sets the foreground brush of the list item to the given brush.

This function was introduced in Qt 4.2.

See also foreground() and setBackground().

### void QListWidgetItem::setHidden ( bool hide )

Hides the item if hide is true; otherwise shows the item.

This function was introduced in Qt 4.2.

See also isHidden().

### void QListWidgetItem::setIcon ( const QIcon & icon )

Sets the icon for the list item to the given icon.

See also icon(), text(), and iconSize.

### void QListWidgetItem::setSelected ( bool select )

Sets the selected state of the item to select.

This function was introduced in Qt 4.2.

See also isSelected().

### void QListWidgetItem::setSizeHint ( const QSize & size )

Sets the size hint for the list item to be size. If no size hint is set, the item delegate will compute the size hint based on the item data.

This function was introduced in Qt 4.1.

See also sizeHint().

### void QListWidgetItem::setStatusTip ( const QString & statusTip )

Sets the status tip for the list item to the text specified by statusTip. QListWidget mouseTracking needs to be enabled for this feature to work.

See also statusTip(), setToolTip(), setWhatsThis(), and QWidget::setMouseTracking().

### void QListWidgetItem::setText ( const QString & text )

Sets the text for the list widget item's to the given text.

See also text().

### void QListWidgetItem::setTextAlignment ( int alignment )

Sets the list item's text alignment to alignment.

See also textAlignment() and Qt::AlignmentFlag.

### void QListWidgetItem::setToolTip ( const QString & toolTip )

Sets the tooltip for the list item to the text specified by toolTip.

See also toolTip(), setStatusTip(), and setWhatsThis().

### void QListWidgetItem::setWhatsThis ( const QString & whatsThis )

Sets the "What's This?" help for the list item to the text specified by whatsThis.

See also whatsThis(), setStatusTip(), and setToolTip().

### QSize QListWidgetItem::sizeHint () const

Returns the size hint set for the list item.

This function was introduced in Qt 4.1.

See also setSizeHint().

### QString QListWidgetItem::statusTip () const

Returns the list item's status tip.

See also setStatusTip().

### QString QListWidgetItem::text () const

Returns the list item's text.

See also setText().

### int QListWidgetItem::textAlignment () const

Returns the text alignment for the list item.

See also setTextAlignment() and Qt::AlignmentFlag.

### QString QListWidgetItem::toolTip () const

Returns the list item's tooltip.

See also setToolTip(), statusTip(), and whatsThis().

### int QListWidgetItem::type () const

Returns the type passed to the QListWidgetItem constructor.

### QString QListWidgetItem::whatsThis () const

Returns the list item's "What's This?" help text.

See also setWhatsThis(), statusTip(), and toolTip().

### void QListWidgetItem::write ( QDataStream & out ) const`[virtual]`

Writes the item to stream out.

See also read().

### bool QListWidgetItem::operator< ( const QListWidgetItem & other ) const`[virtual]`

Returns true if this item's text is less then other item's text; otherwise returns false.

### QListWidgetItem & QListWidgetItem::operator= ( const QListWidgetItem & other )

Assigns other's data and flags to this item. Note that type() and listWidget() are not copied.

This function is useful when reimplementing clone().

See also data() and flags().

## Related Non-Members

### QDataStream & operator<< ( QDataStream & out, const QListWidgetItem & item )

Writes the list widget item item to stream out.

This operator uses QListWidgetItem::write().

See also Serializing Qt Data Types.

### QDataStream & operator>> ( QDataStream & in, QListWidgetItem & item )

Reads a list widget item from stream in into item.

This operator uses QListWidgetItem::read().

See also Serializing Qt Data Types.