Widgets and Layouts

The primary elements for designing user interfaces in Qt.

Widgets

Widgets are the primary elements for creating user interfaces in Qt. Widgets can display data and status information, receive user input, and provide a container for other widgets that should be grouped together. A widget that is not embedded in a parent widget is called a window.

A parent widget containing various child widgets.

A parent widget containing various child widgets.

The QWidget class provides the basic capability to render to the screen, and to handle user input events. All UI elements that Qt provides are either subclasses of QWidget, or are used in connection with a QWidget subclass. Creating custom widgets is done by subclassing QWidget or a suitable subclass and reimplementing the virtual event handlers.

Layouts

Layouts are an elegant and flexible way to automatically arrange child widgets within their container. Each widget reports its size requirements to the layout through the sizeHint and sizePolicy properties, and the layout distributes the available space accordingly.

Qt Designer is a powerful tool for interactively creating and arranging widgets in layouts.

Widget Styles

Styles draw on behalf of widgets and encapsulate the look and feel of a GUI. Qt's built-in widgets use the QStyle class to perform nearly all of their drawing, ensuring that they look exactly like the equivalent native widgets.

Qt Style Sheets are a powerful mechanism that allows you to customize the appearance of widgets, in addition to what is already possible by subclassing QStyle.

The Widget Classes

The following sections list the widget classes. See the Qt Widget Gallery for some examples.

Basic Widgets

These basic widgets (controls), e.g. buttons, comboboxes and scroll bars, are designed for direct use.

QCheckBox

Checkbox with a text label

QComboBox

Combined button and popup list

QCommandLinkButton

Vista style command link button

QDateEdit

Widget for editing dates based on the QDateTimeEdit widget

QDateTimeEdit

Widget for editing dates and times

QDial

Rounded range control (like a speedometer or potentiometer)

QDoubleSpinBox

Spin box widget that takes doubles

QFocusFrame

Focus frame which can be outside of a widget's normal paintable area

QFontComboBox

Combobox that lets the user select a font family

QLCDNumber

Displays a number with LCD-like digits

QLabel

Text or image display

QLineEdit

One-line text editor

QMenu

Menu widget for use in menu bars, context menus, and other popup menus

QProgressBar

Horizontal or vertical progress bar

QPushButton

Command button

QRadioButton

Radio button with a text label

QScrollArea

Scrolling view onto another widget

QScrollBar

Vertical or horizontal scroll bar

QSizeGrip

Resize handle for resizing top-level windows

QSlider

Vertical or horizontal slider

QSpinBox

Spin box widget

QTabBar

Tab bar, e.g. for use in tabbed dialogs

QTabWidget

Stack of tabbed widgets

QTimeEdit

Widget for editing times based on the QDateTimeEdit widget

QToolBox

Column of tabbed widget items

QToolButton

Quick-access button to commands or options, usually used inside a QToolBar

QWidget

The base class of all user interface objects

Advanced Widgets

Advanced GUI widgets, e.g. tab widgets and progress bars, provide more complex user interface controls.

QCalendarWidget

Monthly based calendar widget allowing the user to select a date

QColumnView

Model/view implementation of a column view

QDataWidgetMapper

Mapping between a section of a data model to widgets

QDesktopWidget

Access to screen information on multi-head systems

QListView

List or icon view onto a model

QMacCocoaViewContainer

Widget for Mac OS X that can be used to wrap arbitrary Cocoa views (i.e., NSView subclasses) and insert them into Qt hierarchies

QMacNativeWidget

Widget for Mac OS X that provides a way to put Qt widgets into Carbon or Cocoa hierarchies depending on how Qt was configured

QTableView

Default model/view implementation of a table view

QTreeView

Default model/view implementation of a tree view

QUndoView

Displays the contents of a QUndoStack

QWSEmbedWidget

Enables embedded top-level widgets in Qt for Embedded Linux

QWebView

Widget that is used to view and edit web documents

QX11EmbedContainer

XEmbed container widget

QX11EmbedWidget

XEmbed client widget

Phonon::VideoWidget

Widget that is used to display video

Organizer Widgets

Classes like splitters, tab bars, button groups, etc are used for organizing and grouping GUI primitives into more complex applications and dialogs.

QButtonGroup

Container to organize groups of button widgets

QGroupBox

Group box frame with a title

QSplitter

Implements a splitter widget

QSplitterHandle

Handle functionality of the splitter

QStackedWidget

Stack of widgets where only one widget is visible at a time

QTabWidget

Stack of tabbed widgets

Abstract Widget Classes

The abstract widget classes are base classes. They are not usable as standalone classes but provide functionality when they are subclassed.

QAbstractButton

The abstract base class of button widgets, providing functionality common to buttons

QAbstractScrollArea

Scrolling area with on-demand scroll bars

QAbstractSlider

Integer value within a range

QAbstractSpinBox

Spinbox and a line edit to display values

QDialog

The base class of dialog windows

QFrame

The base class of widgets that can have a frame

Notes provided by the Qt Community

No notes