Class: QgsStoredExpressionManager

Manages stored expressions regarding creation, modification and storing in the project.

Added in version 3.10.

Class Hierarchy

Inheritance diagram of qgis.core.QgsStoredExpressionManager

Base classes

QObject
class qgis.core.QgsStoredExpressionManager[source]

Bases: QObject

addStoredExpression(self, name: str | None, expression: str | None, tag: QgsStoredExpression.Category = QgsStoredExpression.Category.FilterExpression) → str[source]

Adds an expression to the list

Parameters:

  • name (Optional[str]) – optional name of the expression

  • expression (Optional[str]) – expression text

  • tag (QgsStoredExpression.Category = QgsStoredExpression.Category.FilterExpression) – category of the expression use case - default FilterExpression

Return type:

str

Returns:

generated id

addStoredExpressions(self, storedExpressions: Iterable[QgsStoredExpression])[source]

Appends a list of expressions to the existing list

Parameters:

storedExpressions (Iterable[QgsStoredExpression]) – list of expressions and the optional name

clearStoredExpressions(self)[source]

Clears list of stored expressions

findStoredExpressionByExpression(self, expression: str | None, tag: QgsStoredExpression.Category = QgsStoredExpression.Category.All) → QgsStoredExpression[source]

Returns an expression according to the expression text

Parameters:

  • expression (Optional[str]) – id of the expression as identification

  • tag (QgsStoredExpression.Category = QgsStoredExpression.Category.All) – category of the expression use case - default all

Return type:

QgsStoredExpression

readXml(self, layerNode: QDomNode) → bool[source]

Reads the stored expressions in in XML format

Parameters:

layerNode (QDomNode)

Return type:

bool

removeStoredExpression(self, id: str | None)[source]

Removes an expression to the list

Parameters:

id (Optional[str]) – id of the expression as identification

storedExpression(self, id: str | None) → QgsStoredExpression[source]

Returns an expression according to the id

Parameters:

id (Optional[str]) – id of the expression as identification

Return type:

QgsStoredExpression

storedExpressions(self, tag: QgsStoredExpression.Category = QgsStoredExpression.Category.All) → List[QgsStoredExpression]

Returns the list of named expressions

Parameters:

tag (QgsStoredExpression.Category = QgsStoredExpression.Category.All) – category of the expression use case - default all

Return type:

List[QgsStoredExpression]

updateStoredExpression(self, id: str | None, name: str | None, expression: str | None, tag: QgsStoredExpression.Category)[source]

Updates an expression by id.

Parameters:

  • id (Optional[str]) – id of the expression as identification

  • name (Optional[str]) – new name of the expression

  • expression (Optional[str]) – new expression text

  • tag (QgsStoredExpression.Category) – new category of the expression use case

writeXml(self, layerNode: QDomNode) → bool[source]

Writes the stored expressions out in XML format

Parameters:

layerNode (QDomNode)

Return type:

bool