QToolButton Class Reference
[QtGui module]

Detailed Description

The QToolButton class provides a quick-access button to commands or options, usually used inside a QToolBar.

A tool button is a special button that provides quick-access to specific commands or options. As opposed to a normal command button, a tool button usually doesn't show a text label, but shows an icon instead.

Tool buttons are normally created when new QAction instances are created with QToolBar::addAction() or existing actions are added to a toolbar with QToolBar::addAction(). It is also possible to construct tool buttons in the same way as any other widget, and arrange them alongside other widgets in layouts.

One classic use of a tool button is to select tools; for example, the "pen" tool in a drawing program. This would be implemented by using a QToolButton as a toggle button (see setToggleButton()).

QToolButton supports auto-raising. In auto-raise mode, the button draws a 3D frame only when the mouse points at it. The feature is automatically turned on when a button is used inside a QToolBar. Change it with setAutoRaise().

A tool button's icon is set as QIcon. This makes it possible to specify different pixmaps for the disabled and active state. The disabled pixmap is used when the button's functionality is not available. The active pixmap is displayed when the button is auto-raised because the mouse pointer is hovering over it.

The button's look and dimension is adjustable with setToolButtonStyle() and setIconSize(). When used inside a QToolBar in a QMainWindow, the button automatically adjusts to QMainWindow's settings (see QMainWindow::setToolButtonStyle() and QMainWindow::setIconSize()). Instead of an icon, a tool button can also display an arrow symbol, specified with arrowType.

A tool button can offer additional choices in a popup menu. The popup menu can be set using setMenu(). Use setPopupMode() to configure the different modes available for tool buttons with a menu set. The default mode is DelayedPopupMode which is sometimes used with the "Back" button in a web browser. After pressing and holding the button down for a while, a menu pops up showing a list of possible pages to jump to. The default delay is 600 ms; you can adjust it with setPopupDelay().

Qt Assistant's toolbar contains tool buttons that are associated with actions used in other parts of the main window.

See also QPushButton, QToolBar, QMainWindow, QAction, and GUI Design Handbook: Push Button.

Member Type Documentation

enum QToolButton::ToolButtonPopupMode

Describes how a menu should be popped up for tool buttons that has a menu set or contains a list of actions.

Property Documentation

arrowType : Qt::ArrowType

This property holds whether the button displays an arrow instead of a normal icon.

This displays an arrow as the icon for the QToolButton.

By default, this property is set to Qt::NoArrow.

Access functions:

• Qt::ArrowType arrowType () const
• void setArrowType ( Qt::ArrowType type )

autoRaise : bool

This property holds whether auto-raising is enabled or not.

The default is disabled (i.e. false).

This property is currently ignored on Mac OS X when using QMacStyle.

Access functions:

• bool autoRaise () const
• void setAutoRaise ( bool enable )

popupMode : ToolButtonPopupMode

This property describes the way that popup menus are used with tool buttons.

By default, this property is set to DelayedPopup.

Access functions:

• ToolButtonPopupMode popupMode () const
• void setPopupMode ( ToolButtonPopupMode mode )

toolButtonStyle : Qt::ToolButtonStyle

This property holds whether the tool button displays an icon only, text only, or text beside/below the icon.

The default is Qt::ToolButtonIconOnly.

QToolButton automatically connects this slot to the relevant signal in the QMainWindow in which is resides.

Access functions:

• Qt::ToolButtonStyle toolButtonStyle () const
• void setToolButtonStyle ( Qt::ToolButtonStyle style )

Member Function Documentation

QToolButton::QToolButton ( QWidget * parent = 0 )

Constructs an empty tool button with parent parent.

QToolButton::~QToolButton ()

Destroys the object and frees any allocated resources.

QAction * QToolButton::defaultAction () const

Returns the default action.

See also setDefaultAction().

void QToolButton::initStyleOption ( QStyleOptionToolButton * option ) const   [protected]

Initialize option with the values from this QToolButton. This method is useful for subclasses when they need a QStyleOptionToolButton, but don't want to fill in all the information themselves.

See also QStyleOption::initFrom().

QMenu * QToolButton::menu () const

Returns the associated menu, or 0 if no menu has been defined.

See also setMenu().

void QToolButton::paintEvent ( QPaintEvent * event )   [virtual protected]

Paints the button in response to the paint event.

Reimplemented from QWidget.

void QToolButton::setDefaultAction ( QAction * action )   [slot]

Sets the default action to action.

If a tool button has a default action, the action defines the button's properties like text, icon, tool tip, etc.

See also defaultAction().

void QToolButton::setMenu ( QMenu * menu )

Associates the given menu with this tool button.

The menu will be shown according to the button's popupMode.

Ownership of the menu is not transferred to the tool button.

See also menu().

void QToolButton::showMenu ()   [slot]

Shows (pops up) the associated popup menu. If there is no such menu, this function does nothing. This function does not return until the popup menu has been closed by the user.

void QToolButton::triggered ( QAction * action )   [signal]

This signal is emitted when the given action is triggered.

The action may also be associated with other parts of the user interface, such as menu items and keyboard shortcuts. Sharing actions in this way helps make the user interface more consistent and is often less work to implement.