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Qt Class Reference
^{[QtCore module]}

The Qt namespace contains miscellaneous identifiers used throughout the Qt library. More...

Types

• class Alignment
• enum AlignmentFlag { AlignLeft, AlignLeading, AlignRight, AlignTrailing, ..., AlignCenter }
• enum AnchorAttribute { AnchorName, AnchorHref }
• enum ApplicationAttribute { AA_ImmediateWidgetCreation, AA_MSWindowsUseDirect3DByDefault }
• enum ArrowType { NoArrow, UpArrow, DownArrow, LeftArrow, RightArrow }
• enum AspectRatioMode { IgnoreAspectRatio, KeepAspectRatio, KeepAspectRatioByExpanding }
• enum Axis { XAxis, YAxis, ZAxis }
• enum BGMode { TransparentMode, OpaqueMode }
• enum BrushStyle { NoBrush, SolidPattern, Dense1Pattern, Dense2Pattern, ..., TexturePattern }
• enum CaseSensitivity { CaseInsensitive, CaseSensitive }
• enum CheckState { Unchecked, PartiallyChecked, Checked }
• enum ClipOperation { NoClip, ReplaceClip, IntersectClip, UniteClip }
• enum ConnectionType { AutoConnection, DirectConnection, QueuedConnection, AutoCompatConnection, BlockingQueuedConnection }
• enum ContextMenuPolicy { NoContextMenu, PreventContextMenu, DefaultContextMenu, ActionsContextMenu, CustomContextMenu }
• enum Corner { TopLeftCorner, TopRightCorner, BottomLeftCorner, BottomRightCorner }
• enum CursorShape { ArrowCursor, UpArrowCursor, CrossCursor, WaitCursor, ..., CustomCursor }
• enum DateFormat { TextDate, ISODate, LocalDate, SystemLocaleDate, LocaleDate }
• enum DayOfWeek { Monday, Tuesday, Wednesday, Thursday, ..., Sunday }
• enum DockWidgetArea { LeftDockWidgetArea, RightDockWidgetArea, TopDockWidgetArea, BottomDockWidgetArea, ..., NoDockWidgetArea }
• class DockWidgetAreas
• enum DropAction { CopyAction, MoveAction, LinkAction, ActionMask, TargetMoveAction, IgnoreAction }
• class DropActions
• enum EventPriority { HighEventPriority, NormalEventPriority, LowEventPriority }
• enum FillRule { OddEvenFill, WindingFill }
• enum FocusPolicy { NoFocus, TabFocus, ClickFocus, StrongFocus, WheelFocus }
• enum FocusReason { MouseFocusReason, TabFocusReason, BacktabFocusReason, ActiveWindowFocusReason, ..., NoFocusReason }
• enum GlobalColor { color0, color1, black, white, ..., transparent }
• enum HitTestAccuracy { ExactHit, FuzzyHit }
• enum ImageConversionFlag { ColorMode_Mask, AutoColor, ColorOnly, MonoOnly, ..., AvoidDither }
• class ImageConversionFlags
• enum InputMethodQuery { ImMicroFocus, ImFont, ImCursorPosition, ImSurroundingText, ImCurrentSelection }
• enum ItemDataRole { DisplayRole, DecorationRole, EditRole, ToolTipRole, ..., UserRole }
• enum ItemFlag { ItemIsSelectable, ItemIsEditable, ItemIsDragEnabled, ItemIsDropEnabled, ..., ItemIsTristate }
• class ItemFlags
• enum ItemSelectionMode { ContainsItemShape, IntersectsItemShape, ContainsItemBoundingRect, IntersectsItemBoundingRect }
• enum Key { Key_Escape, Key_Tab, Key_Backtab, Key_Backspace, ..., Key_Cancel }
• enum KeyboardModifier { NoModifier, ShiftModifier, ControlModifier, AltModifier, ..., KeyboardModifierMask }
• class KeyboardModifiers
• enum LayoutDirection { LeftToRight, RightToLeft }
• enum MaskMode { MaskInColor, MaskOutColor }
• enum MatchFlag { MatchExactly, MatchFixedString, MatchContains, MatchStartsWith, ..., MatchRecursive }
• class MatchFlags
• enum Modifier { META, SHIFT, CTRL, ALT, MODIFIER_MASK, UNICODE_ACCEL }
• enum MouseButton { NoButton, LeftButton, RightButton, MidButton, ..., MouseButtonMask }
• class MouseButtons
• enum Orientation { Horizontal, Vertical }
• class Orientations
• enum PenCapStyle { FlatCap, SquareCap, RoundCap, MPenCapStyle }
• enum PenJoinStyle { MiterJoin, BevelJoin, RoundJoin, MPenJoinStyle, SvgMiterJoin }
• enum PenStyle { NoPen, SolidLine, DashLine, DotLine, ..., MPenStyle }
• enum ScrollBarPolicy { ScrollBarAsNeeded, ScrollBarAlwaysOff, ScrollBarAlwaysOn }
• enum ShortcutContext { WidgetShortcut, WindowShortcut, ApplicationShortcut }
• enum SortOrder { AscendingOrder, DescendingOrder }
• enum TextElideMode { ElideLeft, ElideRight, ElideMiddle, ElideNone }
• enum TextFlag { TextSingleLine, TextDontClip, TextExpandTabs, TextShowMnemonic, ..., TextJustificationForced }
• enum TextFormat { PlainText, RichText, AutoText, LogText }
• enum TextInteractionFlag { NoTextInteraction, TextSelectableByMouse, TextSelectableByKeyboard, LinksAccessibleByMouse, ..., TextBrowserInteraction }
• class TextInteractionFlags
• enum TimeSpec { LocalTime, UTC }
• enum ToolBarArea { LeftToolBarArea, RightToolBarArea, TopToolBarArea, BottomToolBarArea, ..., NoToolBarArea }
• class ToolBarAreas
• enum ToolButtonStyle { ToolButtonIconOnly, ToolButtonTextOnly, ToolButtonTextBesideIcon, ToolButtonTextUnderIcon }
• enum TransformationMode { FastTransformation, SmoothTransformation }
• enum UIEffect { UI_General, UI_AnimateMenu, UI_FadeMenu, UI_AnimateCombo, ..., UI_AnimateToolBox }
• enum WhiteSpaceMode { WhiteSpaceNormal, WhiteSpacePre, WhiteSpaceNoWrap, WhiteSpaceModeUndefined }
• enum WidgetAttribute { WA_Disabled, WA_UnderMouse, WA_MouseTracking, WA_OpaquePaintEvent, ..., WA_MacAlwaysShowToolWindow }
• class WindowFlags
• enum WindowModality { NonModal, WindowModal, ApplicationModal }
• enum WindowState { WindowNoState, WindowMinimized, WindowMaximized, WindowFullScreen, WindowActive }
• class WindowStates
• enum WindowType { Widget, Window, Dialog, Sheet, ..., WindowStaysOnTopHint }

Static Methods

• QString convertFromPlainText (QString plain, WhiteSpaceMode mode = Qt.WhiteSpacePre)
• QString escape (QString plain)
• bool mightBeRichText (QString)

Qt.AlignmentFlag

This enum type is used to describe alignment. It contains horizontal and vertical flags that can be combined to produce the required effect.

The TextElideMode enum can also be used in many situations to fine-tune the appearance of aligned text.

The horizontal flags are:

The vertical flags are:

You can use only one of the horizontal flags at a time. There is one two-dimensional flag:

You can use at most one horizontal and one vertical flag at a time. Qt.AlignCenter counts as both horizontal and vertical.

Three enum values are useful in applications that can be run in right-to-left mode:

Masks:

Conflicting combinations of flags have undefined meanings.

The Alignment type is a typedef for QFlags<AlignmentFlag>. It stores an OR combination of AlignmentFlag values.

Qt.AnchorAttribute

An anchor has one or more of the following attributes:

Qt.ApplicationAttribute

This enum describes attributes that change the behavior of application-wide features. These are enabled and disabled using QCoreApplication.setAttribute(), and can be tested for with QCoreApplication.testAttribute().

Qt.ArrowType

Qt.AspectRatioMode

This enum type defines what happens to the aspect ratio when scaling an rectangle.

See also QSize.scale() and QImage.scaled().

Qt.Axis

This enum type defines three values to represent the three axes in the cartesian coordinate system.

See also QTransform.rotate() and QTransform.rotateRadians().

Qt.BGMode

Background mode:

Qt.BrushStyle

This enum type defines the brush styles supported by Qt, i.e. the fill pattern of shapes drawn using QPainter.

See also QBrush.

Qt.CaseSensitivity

Qt.CheckState

This enum describes the state of checkable items, controls, and widgets.

See also QCheckBox, Qt.ItemFlags, and Qt.ItemDataRole.

Qt.ClipOperation

Qt.ConnectionType

This enum describes the types of connection that can be used between signals and slots. In particular, it determines whether a particular signal is delivered to a slot immediately or queued for delivery at a later time.

 QObject.connect: Cannot queue arguments of type 'MyType'

call qRegisterMetaType() to register the data type before you establish the connection.

See also Thread Support in Qt, QObject.connect(), and qRegisterMetaType().

Qt.ContextMenuPolicy

This enum type defines the various policies a widget can have with respect to showing a context menu.

Qt.Corner

This enum type specifies a corner in a rectangle:

Qt.CursorShape

This enum type defines the various cursors that can be used.

The standard arrow cursor is the default for widgets in a normal state.

Constant	Value	Description
Qt.ArrowCursor	0	The standard arrow cursor.
Qt.UpArrowCursor	1	An arrow pointing upwards toward the top of the screen.
Qt.CrossCursor	2	A crosshair cursor, typically used to help the user accurately select a point on the screen.
Qt.WaitCursor	3	An hourglass or watch cursor, usually shown during operations that prevent the user from interacting with the application.
Qt.IBeamCursor	4	A caret or ibeam cursor, indicating that a widget can accept and display text input.
Qt.SizeVerCursor	5	A cursor used for elements that are used to vertically resize top-level windows.
Qt.SizeHorCursor	6	A cursor used for elements that are used to horizontally resize top-level windows.
Qt.SizeBDiagCursor	7	A cursor used for elements that are used to diagonally resize top-level windows at their top-right and bottom-left corners.
Qt.SizeFDiagCursor	8	A cursor used for elements that are used to diagonally resize top-level windows at their top-left and bottom-right corners.
Qt.SizeAllCursor	9	A cursor used for elements that are used to resize top-level windows in any direction.
Qt.BlankCursor	10	A blank/invisible cursor, typically used when the cursor shape needs to be hidden.
Qt.SplitVCursor	11	A cursor used for vertical splitters, indicating that a handle can be dragged horizontally to adjust the use of available space.
Qt.SplitHCursor	12	A cursor used for horizontal splitters, indicating that a handle can be dragged vertically to adjust the use of available space.
Qt.PointingHandCursor	13	A pointing hand cursor that is typically used for clickable elements such as hyperlinks.
Qt.ForbiddenCursor	14	A slashed circle cursor, typically used during drag and drop operations to indicate that dragged content cannot be dropped on particular widgets or inside certain regions.
Qt.OpenHandCursor	17	A cursor representing an open hand, typically used to indicate that the area under the cursor is the visible part of a canvas that the user can click and drag in order to scroll around.
Qt.ClosedHandCursor	18	A cursor representing a closed hand, typically used to indicate that a dragging operation is in progress that involves scrolling.
Qt.WhatsThisCursor	15	An arrow with a question mark, typically used
Qt.BusyCursor	16	An hourglass or watch cursor, usually shown during operations that allow the user to interact with the application while they are performed in the background.
Qt.BitmapCursor	24

Qt.DateFormat

Qt.DayOfWeek

Qt.DockWidgetArea

The DockWidgetAreas type is a typedef for QFlags<DockWidgetArea>. It stores an OR combination of DockWidgetArea values.

Qt.DropAction

The DropActions type is a typedef for QFlags<DropAction>. It stores an OR combination of DropAction values.

Qt.EventPriority

This enum can be used to specify event priorities.

 enum CustomEventPriority
 {
     // An important event
     ImportantEventPriority = Qt.HighEventPriority,

     // A more important event
     MoreImportantEventPriority = ImportantEventPriority + 1,

     // A critical event
     CriticalEventPriority = 100 * MoreImportantEventPriority,

     // Not that important
     StatusEventPriority = Qt.LowEventPriority,

     // These are less important than Status events
     IdleProcessingDoneEventPriority = StatusEventPriority - 1
 };

See also QCoreApplication.postEvent().

Qt.FillRule

Specifies which method should be used to fill the paths and polygons.

Qt.FocusPolicy

This enum type defines the various policies a widget can have with respect to acquiring keyboard focus.

Qt.FocusReason

This enum specifies why the focus changed. It will be passed through QWidget.setFocus and can be retrieved in the QFocusEvent sent to the widget upon focus change.

See also Keyboard Focus.

Qt.GlobalColor

Qt's predefined QColor objects:

See also QColor.

Qt.HitTestAccuracy

This type is only available if the QtGui module is imported.

This enum contains the types of accuracy that can be used by the QTextDocument class when testing for mouse clicks on text documents.

This enum is defined in the <QTextDocument> header file.

Qt.ImageConversionFlag

The options marked "(default)" are set if no other values from the list are included (since the defaults are zero):

Color/Mono preference (ignored for QBitmap):

Dithering mode preference for RGB channels:

Dithering mode preference for alpha channel:

Color matching versus dithering preference:

The ImageConversionFlags type is a typedef for QFlags<ImageConversionFlag>. It stores an OR combination of ImageConversionFlag values.

Qt.InputMethodQuery

Qt.ItemDataRole

Each item in the model has a set of data elements associated with it, each with its own role. The roles are used by the view to indicate to the model which type of data it needs.

Qt.ItemFlag

This enum describes the properties of an item:

Note that checkable items need to be given both a suitable set of flags and an initial state, indicating whether the item is checked or not. This is handled automatically for model/view components, but needs to be explicitly set for instances of QListWidgetItem, QTableWidgetItem, and QTreeWidgetItem.

The ItemFlags type is a typedef for QFlags<ItemFlag>. It stores an OR combination of ItemFlag values.

See also QAbstractItemModel.

Qt.ItemSelectionMode

This enum is used in QGraphicsItem, QGraphicsScene and QGraphicsView to specify how items are selected, or how to determine if a shapes and items collide.

See also QGraphicsScene.items(), QGraphicsScene.collidingItems(), QGraphicsView.items(), QGraphicsItem.collidesWithItem(), and QGraphicsItem.collidesWithPath().

Qt.Key

The key names used by Qt.

See also QKeyEvent.key().

Qt.KeyboardModifier

This enum describes the modifier keys.

The KeyboardModifiers type is a typedef for QFlags<KeyboardModifier>. It stores an OR combination of KeyboardModifier values.

See also MouseButton and Modifier.

Qt.LayoutDirection

Specifies the direction of Qt's layouts:

See also QApplication.setLayoutDirection() and QWidget.setLayoutDirection().

Qt.MaskMode

This enum specifies the behavior of the QPixmap.createMaskFromColor() and QImage.createMaskFromColor() functions.

Qt.MatchFlag

This enum describes the type of matches that can be used when searching for items in a model.

The MatchFlags type is a typedef for QFlags<MatchFlag>. It stores an OR combination of MatchFlag values.

See also QString.compare() and QRegExp.

Qt.Modifier

This enum provides shorter names for the keyboard modifier keys supported by Qt.

See also KeyboardModifier and MouseButton.

Qt.MouseButton

This enum type describes the different mouse buttons.

The MouseButtons type is a typedef for QFlags<MouseButton>. It stores an OR combination of MouseButton values.

See also KeyboardModifier and Modifier.

Qt.Orientation

This type is used to signify an object's orientation.

Orientation is used with QScrollBar for example.

The Orientations type is a typedef for QFlags<Orientation>. It stores an OR combination of Orientation values.

Qt.PenCapStyle

This enum type defines the pen cap styles supported by Qt, i.e. the line end caps that can be drawn using QPainter.

Qt.SquareCap	Qt.FlatCap	Qt.RoundCap

See also QPen.

Qt.PenJoinStyle

This enum type defines the pen join styles supported by Qt, i.e. which joins between two connected lines can be drawn using QPainter.

Qt.BevelJoin	Qt.MiterJoin	Qt.RoundJoin

See also QPen.

Qt.PenStyle

This enum type defines the pen styles that can be drawn using QPainter. The styles are:

Qt.SolidLine	Qt.DashLine	Qt.DotLine
Qt.DashDotLine	Qt.DashDotDotLine	Qt.CustomDashLine

See also QPen.

Qt.ScrollBarPolicy

This enum type describes the various modes of QAbstractScrollArea's scroll bars.

(The modes for the horizontal and vertical scroll bars are independent.)

Qt.ShortcutContext

For a QEvent.Shortcut event to occur, the shortcut's key sequence must be entered by the user in a context where the shortcut is active. The possible contexts are these:

Qt.SortOrder

This enum describes how the items in a widget are sorted.

Qt.TextElideMode

This enum specifies where the ellipsis should appear when displaying texts that don't fit:

Qt.ElideMiddle is normally the most appropriate choice for URLs (e.g., "http://www.troll...ovingto/beijing/"), whereas Qt.ElideRight is appropriate for other strings (e.g., "Deploying Applications on Ma...").

See also QAbstractItemView.textElideMode, QFontMetrics.elidedText(), AlignmentFlag, and QTabBar.elideMode.

Qt.TextFlag

This enum type is used to define some modifier flags. Some of these flags only make sense in the context of printing:

Qt.TextFormat

This enum is used in widgets that can display both plain text and rich text, e.g. QLabel. It is used for deciding whether a text string should be interpreted as one or the other. This is normally done by passing one of the enum values to a setTextFormat() function.

Qt.TextInteractionFlag

This enum specifies how a text displaying widget reacts to user input.

The TextInteractionFlags type is a typedef for QFlags<TextInteractionFlag>. It stores an OR combination of TextInteractionFlag values.

Qt.TimeSpec

Qt.ToolBarArea

The ToolBarAreas type is a typedef for QFlags<ToolBarArea>. It stores an OR combination of ToolBarArea values.

Qt.ToolButtonStyle

The style of the tool button, describing how the button's text and icon should be displayed.

Qt.TransformationMode

This enum type defines whether image transformations (e.g., scaling) should be smooth or not.

See also QImage.scaled().

Qt.UIEffect

This enum describes the available UI effects.

By default, Qt will try to use the platform specific desktop settings for each effect. Use the QApplication.setDesktopSettingsAware() function (passing false as argument) to prevent this, and the QApplication.setEffectEnabled() to enable or disable a particular effect.

Note that all effects are disabled on screens running at less than 16-bit color depth.

See also QApplication.setEffectEnabled() and QApplication.setDesktopSettingsAware().

Qt.WhiteSpaceMode

This type is only available if the QtGui module is imported.

This enum describes the types of whitespace mode that are used by the QTextDocument class to meet the requirements of different kinds of textual information.

This enum is defined in the <QTextDocument> header file.

Qt.WidgetAttribute

This enum type is used to specify various widget attributes. Attributes are set and cleared with QWidget.setAttribute(), and queried with QWidget.testAttribute(), although some have special convenience functions which are mentioned below.

Qt.WindowModality

See also QWidget.windowModality and QDialog.

Qt.WindowState

The WindowStates type is a typedef for QFlags<WindowState>. It stores an OR combination of WindowState values.

Qt.WindowType

The WindowFlags type is a typedef for QFlags<WindowType>. It stores an OR combination of WindowType values.

See also QWidget.windowFlags and Window Flags Example.

Method Documentation

QString Qt.convertFromPlainText (QString plain, WhiteSpaceMode mode = Qt.WhiteSpacePre)

This method is only available if the QtGui module is imported.

Converts the plain text string plain to an HTML-formatted paragraph while preserving most of its look.

mode defines how whitespace is handled.

This function is defined in the <QTextDocument> header file.

See also escape() and mightBeRichText().

QString Qt.escape (QString plain)

This method is only available if the QtGui module is imported.

Converts the plain text string plain to a HTML string with HTML metacharacters <, >, and & replaced by HTML entities.

Example:

 QString plain = "#include <QtCore>"
 QString html = Qt.escape(plain);
 // html == "#include &lt;QtCore&gt;"

This function is defined in the <QTextDocument> header file.

See also convertFromPlainText() and mightBeRichText().

bool Qt.mightBeRichText (QString)

This method is only available if the QtGui module is imported.

Returns true if the string text is likely to be rich text; otherwise returns false.

This function uses a fast and therefore simple heuristic. It mainly checks whether there is something that looks like a tag before the first line break. Although the result may be correct for common cases, there is no guarantee.

This function is defined in the <QTextDocument> header file.