QgsExpressionFieldBuffer class

Buffers information about expression fields for a vector layer.

Constructors, destructors, conversion operators

QgsExpressionFieldBuffer() defaulted: Constructor for QgsExpressionFieldBuffer.

void addExpression(const QString& exp, const QgsField& fld): Add an expression to the buffer.
void readXml(const QDomNode& layer_node): Reads expressions from project file.
void removeExpression(int index): Remove an expression from the buffer.
void renameExpression(int index, const QString& name): Renames an expression field at a given index.
void updateExpression(int index, const QString& exp): Changes the expression at a given index.
void updateFields(QgsFields& flds): Adds fields with the expressions buffered in this object to a QgsFields object.
void writeXml(QDomNode& layer_node, QDomDocument& document) const: Saves expressions to xml under the layer node.

Add an expression to the buffer.

Parameters
exp	expression to add
fld	field to add

Remove an expression from the buffer.

Parameters
index	index of expression to remove

Renames an expression field at a given index.

Parameters
index	The index of the expression to change
name	New name for field

Changes the expression at a given index.

Parameters
index	The index of the expression to change
exp	The new expression to set

Adds fields with the expressions buffered in this object to a QgsFields object.

Parameters
flds	The fields to be updated