Class: QgsFilterLineEdit¶

QLineEdit subclass with built in support for clearing the widget’s value and handling custom null value representations.

When using QgsFilterLineEdit the value(), setValue() and clearValue() methods should be used instead of QLineEdit’s text(), setText() and clear() methods, and the valueChanged() signal should be used instead of textChanged().

Class Hierarchy¶

Base classes¶

QLineEdit
QWidget
QObject
QPaintDevice

Subclasses¶

`QgsFieldValuesLineEdit`	A line edit with an autocompleter which takes unique values from a vector layer’s fields. The autocompleter is populated from the vector layer in the background to ensure responsive interaction with the widget.
`QgsHighlightableLineEdit`	A `QgsFilterLineEdit` subclass with the ability to “highlight” the edges of the widget.

Methods

`clearMode`	Returns the clear mode for the widget.
`clearValue`	Clears the widget and resets it to the null value.
`defaultValue`	Returns the default value for the widget.
`event`	Reimplemented to enable/disable the clear action depending on read-only status
`hasStateStored`	Returns if a state is already saved
`isNull`	Determine if the current text represents null.
`nullValue`	Returns the string used for representing null values in the widget.
`restoreState`	Restores the current state of the line edit (selection and cursor position)
`selectOnFocus`	Will select all text when this widget receives the focus.
`setClearMode`	Sets the clear mode for the widget.
`setDefaultValue`	Sets the default value for the widget.
`setNullValue`	Sets the string representation for null values in the widget.
`setSelectOnFocus`	Will select all text when this widget receives the focus.
`setShowClearButton`	Sets whether the widget's clear button is visible.
`setShowSearchIcon`	Define if a search icon shall be shown on the left of the image when no text is entered
`setShowSpinner`	Show a spinner icon.
`setValue`	Sets the current text for the widget with support for handling null values.
`showClearButton`	Returns `True` if the widget's clear button is visible.
`showSearchIcon`	Returns if a search icon shall be shown on the left of the image when no text is entered
`showSpinner`	Show a spinner icon.
`storeState`	Stores the current state of the line edit (selection and cursor position)
`value`	Returns the text of this edit with support for handling null values.

Signals

`cleared`	Emitted when the widget is cleared
`selectOnFocusChanged`	Will select all text when this widget receives the focus.
`showSpinnerChanged`	Show a spinner icon.
`valueChanged`	Same as `textChanged()` but with support for null values.

Attributes

`ClearToDefault`
`ClearToNull`

class qgis.gui.QgsFilterLineEdit[source]¶

Bases: QLineEdit

__init__(parent: QWidget | None = None, nullValue: str | None = '')

Constructor for QgsFilterLineEdit.

Parameters:

parent (Optional[QWidget] = None) – parent widget
nullValue (Optional[str] = '') – string for representing null values

class ClearMode¶: Bases: int

ClearToDefault = 1¶

ClearToNull = 0¶

clearMode(self) → QgsFilterLineEdit.ClearMode[source]¶

Returns the clear mode for the widget. The clear mode defines the behavior of the widget when its value is cleared. This defaults to ClearToNull.

See also

setClearMode()

Return type:: QgsFilterLineEdit.ClearMode

clearValue(self)[source]¶: Clears the widget and resets it to the null value.

See also

nullValue()

signal cleared[source]¶: Emitted when the widget is cleared

See also

clearValue()

defaultValue(self) → str[source]¶

Returns the default value for the widget. The default value is a value which the widget will be reset to if it is cleared and the clearMode() is equal to ClearToDefault.

See also

setDefaultValue()

See also

clearMode()

Return type:: str

event(self, event: QEvent | None) → bool[source]¶

Reimplemented to enable/disable the clear action depending on read-only status

Parameters:: event (Optional[QEvent])
Return type:: bool

hasStateStored(self) → bool[source]¶

Returns if a state is already saved

Added in version 3.14.

Return type:: bool

isNull(self) → bool[source]¶

Determine if the current text represents null.

Return type:: bool
Returns:: True if the widget’s value is null.

See also

nullValue()

nullValue(self) → str[source]¶

Returns the string used for representing null values in the widget.

See also

setNullValue()

See also

isNull()

Return type:: str

restoreState(self)[source]¶: Restores the current state of the line edit (selection and cursor position)

Added in version 3.14.

selectOnFocus(self) → bool[source]¶

Will select all text when this widget receives the focus.

Return type:: bool

signal selectOnFocusChanged[source]¶: Will select all text when this widget receives the focus.

setClearMode(self, mode: QgsFilterLineEdit.ClearMode)[source]¶

Sets the clear mode for the widget. The clear mode defines the behavior of the widget when its value is cleared. This defaults to ClearToNull.

See also

clearMode()

Parameters:: mode (QgsFilterLineEdit.ClearMode)

setDefaultValue(self, defaultValue: str | None)[source]¶

Sets the default value for the widget. The default value is a value which the widget will be reset to if it is cleared and the clearMode() is equal to ClearToDefault.

Parameters:: defaultValue (Optional[str]) – default value

See also

defaultValue()

See also

clearMode()

setNullValue(self, nullValue: str | None)[source]¶

Sets the string representation for null values in the widget. This does not affect the values returned for null values by value(), rather it only affects the text that is shown to users when the widget’s value is null.

Parameters:: nullValue (Optional[str]) – string to show when widget’s value is null

See also

nullValue()

setSelectOnFocus(self, selectOnFocus: bool)[source]¶

Will select all text when this widget receives the focus.

Parameters:: selectOnFocus (bool)

setShowClearButton(self, visible: bool)[source]¶

Sets whether the widget’s clear button is visible.

Parameters:: visible (bool) – set to False to hide the clear button

See also

showClearButton()

setShowSearchIcon(self, visible: bool)[source]¶

Define if a search icon shall be shown on the left of the image when no text is entered

Parameters:: visible (bool) – set to False to hide the search icon

setShowSpinner(self, showSpinner: bool)[source]¶

Show a spinner icon. This can be used for search boxes to indicate that something is going on in the background.

Parameters:: showSpinner (bool)

setValue(self, value: str | None)[source]¶

Sets the current text for the widget with support for handling null values.

Parameters:: value (Optional[str]) – The text to set. If a null string is provided, the text shown in the widget will be set to the current nullValue().

See also

value()

showClearButton(self) → bool[source]¶

Returns True if the widget’s clear button is visible.

See also

setShowClearButton()

Return type:: bool

showSearchIcon(self) → bool[source]¶

Returns if a search icon shall be shown on the left of the image when no text is entered

Return type:: bool

showSpinner(self) → bool[source]¶

Show a spinner icon. This can be used for search boxes to indicate that something is going on in the background.

Return type:: bool

signal showSpinnerChanged[source]¶: Show a spinner icon. This can be used for search boxes to indicate that something is going on in the background.

storeState(self)[source]¶: Stores the current state of the line edit (selection and cursor position)

Added in version 3.14.

value(self) → str[source]¶

Returns the text of this edit with support for handling null values. If the text in the widget matches the current nullValue() then the returned value will be a null string.

Return type:: str
Returns:: Current text (or null string if it matches the nullValue() property )

See also

setValue()

signal valueChanged(value: str)[source]¶

Same as textChanged() but with support for null values.

Parameters:: value (str) – The current text or null string if it matches the nullValue() property.