Qt Cheat Sheet
Base Classes
QApplication
The QApplication class manages the GUI application's control flow and main settings.
QApplication specializes QGuiApplication with some functionality needed for QWidget-based applications. It handles widget specific initialization, finalization.
QMainWindow
The QMainWindow class provides a main application window.
A main window provides a framework for building an application's user interface. Qt has QMainWindow and its related classes for main window management. QMainWindow has its own layout to which you can add QToolBars, QDockWidgets, a QMenuBar, and a QStatusBar. The layout has a center area that can be occupied by any kind of widget.
QWidget
The QWidget class is the base class of all user interface objects.
The widget is the atom of the user interface: it receives mouse, keyboard and other events from the window system, and paints a representation of itself on the screen. Every widget is rectangular, and they are sorted in a Z-order. A widget is clipped by its parent and by the widgets in front of it.
A widget that is not embedded in a parent widget is called a window. Usually, windows have a frame and a title bar, although it is also possible to create windows without such decoration using suitable window flags). In Qt, QMainWindow and the various subclasses of QDialog are the most common window types.
UI Layouts
The layouts define the way widgets are layed out on the canvas.
QFormLayout
The QFormLayout class manages forms of input widgets and their associated labels.
QFormLayout is a convenience layout class that lays out its children in a two-column form. The left column consists of labels and the right column consists of "field" widgets (line editors, spin boxes, etc.).
QGridLayout
The QGridLayout class lays out widgets in a grid.
QHBoxLayout
The QHBoxLayout class lines up widgets horizontally.
This class is used to construct horizontal box layout objects. See QBoxLayout for details.
QStackedLayout
The QStackedLayout class provides a stack of widgets where only one widget is visible at a time.
QStackedLayout can be used to create a user interface similar to the one provided by QTabWidget. There is also a convenience QStackedWidgetclass built on top of QStackedLayout.
QTabWidget
The QTabWidget class provides a stack of tabbed widgets.
QVBoxLayout
The QVBoxLayout class lines up widgets vertically.
This class is used to construct vertical box layout objects. See QBoxLayout for details.
UI Widgets
Widgets are all derived by baseclass QWidget.
Most common Qt widgets
QWidget
The QWidget class is the base class of all user interface objects.
Often used properties/methods:
QCheckBox
A QCheckBox is an option button that can be switched on (checked) or off (unchecked). Checkboxes are typically used to represent features in an application that can be enabled or disabled without affecting others. Different types of behavior can be implemented. For example, a QButtonGroup can be used to group check buttons logically, allowing exclusive checkboxes. However, QButtonGroup does not provide any visual representation.
QCheckBox => QAbstractButton => QWidget => QObject
QComboBox
A QComboBox provides a means of presenting a list of options to the user in a way that takes up the minimum amount of screen space.
A combobox is a selection widget that displays the current item, and can pop up a list of selectable items. A combobox may be editable, allowing the user to modify each item in the list.
QFrame
Ref: C++
The QFrame class is the base class of widgets that can have a frame.
QMenu uses this to "raise" the menu above the surrounding screen. QProgressBar has a "sunken" look. QLabel has a flat look. The frames of widgets like these can be changed.
QLabel
QLabel is used for displaying text or an image. No user interaction functionality is provided. The visual appearance of the label can be configured in various ways, and it can be used for specifying a focus mnemonic key for another widget.
QLineEdit
A line edit allows the user to enter and edit a single line of plain text with a useful collection of editing functions, including undo and redo, cut and paste, and drag and drop (see setDragEnabled()).
QListWidget
The QListWidget class provides an item-based list widget.
QProgressBar
Ref: C++
The QProgressBar widget provides a horizontal or vertical progress bar.
QPushButton
The QPushButton widget provides a command button.
QRadioButton
The QRadioButton widget provides a radio button with a text label.
QSlider
Ref: C++
The QSlider widget provides a vertical or horizontal slider.
QSplitter
The QSplitter class implements a splitter widget.
A splitter lets the user control the size of child widgets by dragging the boundary between them. Any number of widgets may be controlled by a single splitter. The typical use of a QSplitter is to create several widgets and add them using insertWidget() or addWidget().
QTableWidget
The QTableWidget class provides an item-based table view with a default model.
Table widgets provide standard table display facilities for applications. The items in a QTableWidget are provided by QTableWidgetItem.
QTreeView
(Model/View)
The QTreeView class provides a default model/view implementation of a tree view.
A QTreeView implements a tree representation of items from a model. This class is used to provide standard hierarchical lists that were previously provided by the QListView class, but using the more flexible approach provided by Qt's model/view architecture.
QTreeView implements the interfaces defined by the QAbstractItemView class to allow it to display data provided by models derived from the QAbstractItemModel class.
QTreeWidget
The QTreeWidget class provides a tree view that uses a predefined tree model.
The QTreeWidget class is a convenience class that provides a standard tree widget with a classic item-based interface similar to that used by the QListView class in Qt 3. This class is based on Qt's Model/View architecture and uses a default model to hold items, each of which is a QTreeWidgetItem.
Misc. Classes
QBasicTimer
Ref: C++
The QBasicTimer class provides timer events for objects.
QSize
The QSize class defines the size of a two-dimensional object using integer point precision.
Misc
Qt Stylesheet Reference: A list of various information about Stylesheets