Subgroup: Expression

Class: QgsExpressionLineEdit¶

class qgis.gui.QgsExpressionLineEdit¶

Bases: PyQt5.QtWidgets.QWidget

The QgsExpressionLineEdit widget includes a line edit for entering expressions together with a button to open the expression creation dialog.

This widget is designed for use in contexts where no layer fields are available for use in an expression. In contexts where the expression is directly associated with a layer and fields can be used, then QgsFieldExpressionWidget is a more appropriate choice as it gives users direct access to select fields from a drop-down list.

QgsExpressionLineEdit also supports a multiline editor mode which is useful where more space is available for the widget, but where QgsExpressionBuilderWidget is too complex or large for use.

New in version 3.0: Methods

`acceptDrops`
`accessibleDescription`
`accessibleName`
`actionEvent`
`actions`
`activateWindow`
`addAction`
`addActions`
`adjustSize`
`autoFillBackground`
`backgroundRole`
`baseSize`
`blockSignals`
`changeEvent`
`childAt`	childAt(self, int, int) -> QWidget
`childEvent`
`children`
`childrenRect`
`childrenRegion`
`clearFocus`
`clearMask`
`close`
`closeEvent`
`colorCount`
`connectNotify`
`contentsMargins`
`contentsRect`
`contextMenuEvent`
`contextMenuPolicy`
`create`
`createWindowContainer`
`cursor`
`customEvent`
`deleteLater`
`depth`
`destroy`
`devType`
`devicePixelRatio`
`devicePixelRatioF`
`devicePixelRatioFScale`
`disconnect`
`disconnectNotify`
`dragEnterEvent`
`dragLeaveEvent`
`dragMoveEvent`
`dropEvent`
`dumpObjectInfo`
`dumpObjectTree`
`dynamicPropertyNames`
`effectiveWinId`
`ensurePolished`
`enterEvent`
`event`
`eventFilter`
`expression`	Returns the current expression shown in the widget.
`expressionDialogTitle`	Returns the title used for the expression dialog.
`find`
`findChild`	findChild(self, Tuple, name: str = ‘’, options: Union[Qt.FindChildOptions, Qt.FindChildOption] = Qt.FindChildrenRecursively) -> QObject
`findChildren`	findChildren(self, Tuple, name: str = ‘’, options: Union[Qt.FindChildOptions, Qt.FindChildOption] = Qt.FindChildrenRecursively) -> List[QObject]
`focusInEvent`
`focusNextChild`
`focusNextPrevChild`
`focusOutEvent`
`focusPolicy`
`focusPreviousChild`
`focusProxy`
`focusWidget`
`font`
`fontInfo`
`fontMetrics`
`foregroundRole`
`frameGeometry`
`frameSize`
`geometry`
`getContentsMargins`
`grab`
`grabGesture`
`grabKeyboard`
`grabMouse`	grabMouse(self, Union[QCursor, Qt.CursorShape])
`grabShortcut`
`graphicsEffect`
`graphicsProxyWidget`
`hasFocus`
`hasHeightForWidth`
`hasMouseTracking`
`hasTabletTracking`
`height`
`heightForWidth`
`heightMM`
`hide`
`hideEvent`
`inherits`
`initPainter`
`inputMethodEvent`
`inputMethodHints`
`inputMethodQuery`
`insertAction`
`insertActions`
`installEventFilter`
`isActiveWindow`
`isAncestorOf`
`isEnabled`
`isEnabledTo`
`isFullScreen`
`isHidden`
`isLeftToRight`
`isMaximized`
`isMinimized`
`isModal`
`isRightToLeft`
`isSignalConnected`
`isValidExpression`	Returns true if the current expression is valid.
`isVisible`
`isVisibleTo`
`isWidgetType`
`isWindow`
`isWindowModified`
`isWindowType`
`keyPressEvent`
`keyReleaseEvent`
`keyboardGrabber`
`killTimer`
`layout`
`layoutDirection`
`leaveEvent`
`locale`
`logicalDpiX`
`logicalDpiY`
`lower`
`mapFrom`
`mapFromGlobal`
`mapFromParent`
`mapTo`
`mapToGlobal`
`mapToParent`
`mask`
`maximumHeight`
`maximumSize`
`maximumWidth`
`metaObject`
`metric`
`minimumHeight`
`minimumSize`
`minimumSizeHint`
`minimumWidth`
`mouseDoubleClickEvent`
`mouseGrabber`
`mouseMoveEvent`
`mousePressEvent`
`mouseReleaseEvent`
`move`	move(self, int, int)
`moveEvent`
`moveToThread`
`nativeEvent`
`nativeParentWidget`
`nextInFocusChain`
`normalGeometry`
`objectName`
`overrideWindowFlags`
`overrideWindowState`
`paintEngine`
`paintEvent`
`paintingActive`
`palette`
`parent`
`parentWidget`
`physicalDpiX`
`physicalDpiY`
`pos`
`previousInFocusChain`
`property`
`pyqtConfigure`	Each keyword argument is either the name of a Qt property or a Qt signal.
`raise_`
`receivers`
`rect`
`registerExpressionContextGenerator`	Register an expression context generator class that will be used to retrieve an expression context for the widget.
`releaseKeyboard`
`releaseMouse`
`releaseShortcut`
`removeAction`
`removeEventFilter`
`render`	render(self, QPainter, targetOffset: QPoint = QPoint(), sourceRegion: QRegion = QRegion(), flags: Union[QWidget.RenderFlags, QWidget.RenderFlag] = QWidget.RenderFlags(QWidget.DrawWindowBackground\|QWidget.DrawChildren))
`repaint`	repaint(self, int, int, int, int)
`resize`	resize(self, int, int)
`resizeEvent`
`restoreGeometry`
`saveGeometry`
`scroll`	scroll(self, int, int, QRect)
`sender`
`senderSignalIndex`
`setAcceptDrops`
`setAccessibleDescription`
`setAccessibleName`
`setAttribute`
`setAutoFillBackground`
`setBackgroundRole`
`setBaseSize`	setBaseSize(self, QSize)
`setContentsMargins`	setContentsMargins(self, QMargins)
`setContextMenuPolicy`
`setCursor`
`setDisabled`
`setEnabled`
`setExpression`	Sets the current expression to show in the widget.
`setExpressionDialogTitle`	Sets the title used in the expression builder dialog
`setFixedHeight`
`setFixedSize`	setFixedSize(self, int, int)
`setFixedWidth`
`setFocus`	setFocus(self, Qt.FocusReason)
`setFocusPolicy`
`setFocusProxy`
`setFont`
`setForegroundRole`
`setGeomCalculator`	Set the geometry calculator used in the expression dialog.
`setGeometry`	setGeometry(self, int, int, int, int)
`setGraphicsEffect`
`setHidden`
`setInputMethodHints`
`setLayer`	Sets a layer associated with the widget.
`setLayout`
`setLayoutDirection`
`setLocale`
`setMask`	setMask(self, QRegion)
`setMaximumHeight`
`setMaximumSize`	setMaximumSize(self, QSize)
`setMaximumWidth`
`setMinimumHeight`
`setMinimumSize`	setMinimumSize(self, QSize)
`setMinimumWidth`
`setMouseTracking`
`setMultiLine`	Sets whether the widget should show a multiline text editor.
`setObjectName`
`setPalette`
`setParent`	setParent(self, QWidget, Union[Qt.WindowFlags, Qt.WindowType])
`setProperty`
`setShortcutAutoRepeat`
`setShortcutEnabled`
`setSizeIncrement`	setSizeIncrement(self, QSize)
`setSizePolicy`	setSizePolicy(self, QSizePolicy.Policy, QSizePolicy.Policy)
`setStatusTip`
`setStyle`
`setStyleSheet`
`setTabOrder`
`setTabletTracking`
`setToolTip`
`setToolTipDuration`
`setUpdatesEnabled`
`setVisible`
`setWhatsThis`
`setWindowFilePath`
`setWindowFlag`
`setWindowFlags`
`setWindowIcon`
`setWindowIconText`
`setWindowModality`
`setWindowModified`
`setWindowOpacity`
`setWindowRole`
`setWindowState`
`setWindowTitle`
`sharedPainter`
`show`
`showEvent`
`showFullScreen`
`showMaximized`
`showMinimized`
`showNormal`
`signalsBlocked`
`size`
`sizeHint`
`sizeIncrement`
`sizePolicy`
`stackUnder`
`startTimer`
`statusTip`
`style`
`styleSheet`
`tabletEvent`
`testAttribute`
`thread`
`timerEvent`
`toolTip`
`toolTipDuration`
`tr`
`underMouse`
`ungrabGesture`
`unsetCursor`
`unsetLayoutDirection`
`unsetLocale`
`update`	update(self, QRect)
`updateGeometry`
`updateMicroFocus`
`updatesEnabled`
`visibleRegion`
`whatsThis`
`wheelEvent`
`width`
`widthMM`
`winId`
`window`
`windowFilePath`
`windowFlags`
`windowHandle`
`windowIcon`
`windowIconText`
`windowModality`
`windowOpacity`
`windowRole`
`windowState`
`windowTitle`
`windowType`
`x`
`y`

Attributes

`DrawChildren`
`DrawWindowBackground`
`IgnoreMask`
`PdmDepth`
`PdmDevicePixelRatio`
`PdmDevicePixelRatioScaled`
`PdmDpiX`
`PdmDpiY`
`PdmHeight`
`PdmHeightMM`
`PdmNumColors`
`PdmPhysicalDpiX`
`PdmPhysicalDpiY`
`PdmWidth`
`PdmWidthMM`
`customContextMenuRequested`	customContextMenuRequested(self, QPoint) [signal]
`destroyed`	destroyed(self, QObject = None) [signal]
`expressionChanged`	Emitted when the expression is changed.
`objectNameChanged`	objectNameChanged(self, str) [signal]
`staticMetaObject`
`windowIconChanged`	windowIconChanged(self, QIcon) [signal]
`windowIconTextChanged`	windowIconTextChanged(self, str) [signal]
`windowTitleChanged`	windowTitleChanged(self, str) [signal]

actionEvent()¶

changeEvent(self, event: QEvent)¶

childEvent()¶

closeEvent()¶

connectNotify()¶

contextMenuEvent()¶

create()¶

customEvent()¶

destroy()¶

disconnectNotify()¶

dragEnterEvent()¶

dragLeaveEvent()¶

dragMoveEvent()¶

dropEvent()¶

enterEvent()¶

event()¶

expression(self) → str¶: Returns the current expression shown in the widget.

See also

setExpression()

expressionChanged¶

Emitted when the expression is changed.

Parameters:	expression – new expression [signal]

expressionDialogTitle(self) → str¶: Returns the title used for the expression dialog.

See also

setExpressionDialogTitle()

focusInEvent()¶

focusNextChild()¶

focusNextPrevChild()¶

focusOutEvent()¶

focusPreviousChild()¶

hideEvent()¶

initPainter()¶

inputMethodEvent()¶

isSignalConnected()¶

isValidExpression(self) → Tuple[bool, str]¶

Returns true if the current expression is valid.

Parameters:	expressionError – will be set to any generated error message if specified

keyPressEvent()¶

keyReleaseEvent()¶

leaveEvent()¶

metric()¶

mouseDoubleClickEvent()¶

mouseMoveEvent()¶

mousePressEvent()¶

mouseReleaseEvent()¶

moveEvent()¶

nativeEvent()¶

paintEvent()¶

receivers()¶

registerExpressionContextGenerator(self, generator: QgsExpressionContextGenerator)¶

Register an expression context generator class that will be used to retrieve an expression context for the widget.

Parameters:	generator – A QgsExpressionContextGenerator class that will be used to

create an expression context when required.

resizeEvent()¶

sender()¶

senderSignalIndex()¶

setExpression(self, expression: str)¶

Sets the current expression to show in the widget.

Parameters:	expression – expression string