An ordered stack of QgsPropertyCollection containers, where collections added later to the stack will take priority over earlier collections. More...

#include <qgspropertycollection.h>

Inheritance diagram for QgsPropertyCollectionStack:

[legend]

Public Member Functions
	QgsPropertyCollectionStack ()=default
	Constructor for QgsPropertyCollectionStack. More...

	QgsPropertyCollectionStack (const QgsPropertyCollectionStack &other)
	Copy constructor. More...

	~QgsPropertyCollectionStack () override

void	appendCollection (QgsPropertyCollection *collection)
	Appends a collection to the end of the stack, and transfers ownership of the collection to the stack. More...

QgsPropertyCollection *	at (int index)
	Returns the collection at the corresponding index from the stack. More...

const QgsPropertyCollection *	at (int index) const
	Returns the collection at the corresponding index from the stack. More...

void	clear () override
	Removes all collections from the stack. More...

QgsPropertyCollection *	collection (const QString &name)
	Returns the first collection with a matching name from the stack. More...

int	count () const
	Returns the number of collections contained within the stack. More...

bool	hasActiveProperties () const override
	Returns `true` if the collection has any active properties, or `false` if all properties within the collection are deactivated. More...

bool	hasDynamicProperties () const override
	Returns `true` if the collection has any active, non-static properties, or `false` if either all non-static properties within the collection are deactivated or if the collection only contains static properties. More...

bool	hasProperty (int key) const override
	Returns `true` if the collection contains a property with the specified key. More...

bool	isActive (int key) const override
	Returns `true` if the stack contains an active property with the specified key. More...

bool	loadVariant (const QVariant &collection, const QgsPropertiesDefinition &definitions) override
	Loads this property collection from a QVariantMap, wrapped in a QVariant. More...

QgsPropertyCollectionStack &	operator= (const QgsPropertyCollectionStack &other)

bool	prepare (const QgsExpressionContext &context=QgsExpressionContext()) const override
	Prepares the collection against a specified expression context. More...

QgsProperty	property (int key) const override
	Returns the highest priority property with a matching key from within the stack. More...

QSet< int >	propertyKeys () const override
	Returns a list of property keys contained within the collection. More...

QSet< QString >	referencedFields (const QgsExpressionContext &context=QgsExpressionContext(), bool ignoreContext=false) const override
	Returns the set of any fields referenced by the active properties from the stack. More...

QVariant	toVariant (const QgsPropertiesDefinition &definitions) const override
	Saves this property collection to a QVariantMap, wrapped in a QVariant. More...

QVariant	value (int key, const QgsExpressionContext &context, const QVariant &defaultValue=QVariant()) const override
	Returns the calculated value of the highest priority property with the specified key from within the stack. More...

Public Member Functions inherited from QgsAbstractPropertyCollection
	QgsAbstractPropertyCollection (const QString &name=QString())
	Constructor for QgsAbstractPropertyCollection. More...

virtual	~QgsAbstractPropertyCollection ()=default

QString	name () const
	Returns the descriptive name of the property collection. More...

virtual bool	readXml (const QDomElement &collectionElem, const QgsPropertiesDefinition &definitions)
	Reads property collection state from an XML element. More...

void	setName (const QString &name)
	Sets the descriptive name for the property collection. More...

bool	valueAsBool (int key, const QgsExpressionContext &context, bool defaultValue=false, bool *ok=nullptr) const
	Calculates the current value of the property with the specified key and interprets it as an boolean. More...

QColor	valueAsColor (int key, const QgsExpressionContext &context, const QColor &defaultColor=QColor(), bool *ok=nullptr) const
	Calculates the current value of the property with the specified key and interprets it as a color. More...

QDateTime	valueAsDateTime (int key, const QgsExpressionContext &context, const QDateTime &defaultDateTime=QDateTime(), bool *ok=nullptr) const
	Calculates the current value of the property with the specified key and interprets it as a datetime. More...

double	valueAsDouble (int key, const QgsExpressionContext &context, double defaultValue=0.0, bool *ok=nullptr) const
	Calculates the current value of the property with the specified key and interprets it as a double. More...

int	valueAsInt (int key, const QgsExpressionContext &context, int defaultValue=0, bool *ok=nullptr) const
	Calculates the current value of the property with the specified key and interprets it as an integer. More...

QString	valueAsString (int key, const QgsExpressionContext &context, const QString &defaultString=QString(), bool *ok=nullptr) const
	Calculates the current value of the property with the specified key and interprets it as a string. More...

virtual bool	writeXml (QDomElement &collectionElem, const QgsPropertiesDefinition &definitions) const
	Writes the current state of the property collection into an XML element. More...

Detailed Description

An ordered stack of QgsPropertyCollection containers, where collections added later to the stack will take priority over earlier collections.

Since: QGIS 3.0

Definition at line 405 of file qgspropertycollection.h.

Constructor & Destructor Documentation

◆ QgsPropertyCollectionStack() [1/2]

QgsPropertyCollectionStack::QgsPropertyCollectionStack ( )

default

Constructor for QgsPropertyCollectionStack.

◆ ~QgsPropertyCollectionStack()

QgsPropertyCollectionStack::~QgsPropertyCollectionStack ( )

override

Definition at line 377 of file qgspropertycollection.cpp.

◆ QgsPropertyCollectionStack() [2/2]

QgsPropertyCollectionStack::QgsPropertyCollectionStack ( const QgsPropertyCollectionStack & other )

Copy constructor.

Definition at line 382 of file qgspropertycollection.cpp.

Member Function Documentation

◆ appendCollection()

void QgsPropertyCollectionStack::appendCollection ( QgsPropertyCollection * collection )

Appends a collection to the end of the stack, and transfers ownership of the collection to the stack.

Properties from the newly added collection will take priority over any existing properties with the same name.

Parameters

collection collection to append. Ownership is transferred to the stack.

Definition at line 417 of file qgspropertycollection.cpp.

◆ at() [1/2]

QgsPropertyCollection * QgsPropertyCollectionStack::at ( int index )

Returns the collection at the corresponding index from the stack.

Parameters

index position of collection, 0 based

Returns: collection if one exists at the specified index

Definition at line 422 of file qgspropertycollection.cpp.

◆ at() [2/2]

const QgsPropertyCollection * QgsPropertyCollectionStack::at ( int index ) const

Returns the collection at the corresponding index from the stack.

Parameters

index position of collection, 0 based

Returns: collection if one exists at the specified index

Note: not available in Python bindings

Definition at line 427 of file qgspropertycollection.cpp.

◆ clear()

void QgsPropertyCollectionStack::clear ( )

overridevirtual

Removes all collections from the stack.

Implements QgsAbstractPropertyCollection.

Definition at line 411 of file qgspropertycollection.cpp.

◆ collection()

QgsPropertyCollection * QgsPropertyCollectionStack::collection ( const QString & name )

Returns the first collection with a matching name from the stack.

Parameters

name	name of collection to find

Returns: collection if one exists with the specified name

Definition at line 432 of file qgspropertycollection.cpp.

◆ count()

int QgsPropertyCollectionStack::count ( ) const

Returns the number of collections contained within the stack.

Definition at line 406 of file qgspropertycollection.cpp.

◆ hasActiveProperties()

bool QgsPropertyCollectionStack::hasActiveProperties ( ) const

overridevirtual

Returns true if the collection has any active properties, or false if all properties within the collection are deactivated.

See also: isActive(); hasDynamicProperties()

Implements QgsAbstractPropertyCollection.

Definition at line 443 of file qgspropertycollection.cpp.

◆ hasDynamicProperties()

bool QgsPropertyCollectionStack::hasDynamicProperties ( ) const

overridevirtual

Returns true if the collection has any active, non-static properties, or false if either all non-static properties within the collection are deactivated or if the collection only contains static properties.

See also: hasActiveProperties()

Implements QgsAbstractPropertyCollection.

Definition at line 454 of file qgspropertycollection.cpp.

◆ hasProperty()

bool QgsPropertyCollectionStack::hasProperty ( int key ) const

overridevirtual

Returns true if the collection contains a property with the specified key.

Parameters

key	integer key for property. The intended use case is that a context specific enum is cast to int and used for the key value.

See also: property()

Implements QgsAbstractPropertyCollection.

Definition at line 530 of file qgspropertycollection.cpp.

◆ isActive()

bool QgsPropertyCollectionStack::isActive ( int key ) const

overridevirtual

Returns true if the stack contains an active property with the specified key.

Parameters

key	integer key for property to test. The intended use case is that a context specific enum is cast to int and used for the key value.

See also: hasActiveProperties()

Implements QgsAbstractPropertyCollection.

Definition at line 465 of file qgspropertycollection.cpp.

◆ loadVariant()

bool QgsPropertyCollectionStack::loadVariant	(	const QVariant &	configuration,
		const QgsPropertiesDefinition &	definitions
	)

overridevirtual

Loads this property collection from a QVariantMap, wrapped in a QVariant.

You can use QgsXmlUtils::readVariant to save it to an XML document.

See also: toVariant()

Implements QgsAbstractPropertyCollection.

Definition at line 560 of file qgspropertycollection.cpp.

◆ operator=()

QgsPropertyCollectionStack & QgsPropertyCollectionStack::operator= ( const QgsPropertyCollectionStack & other )

Definition at line 393 of file qgspropertycollection.cpp.

◆ prepare()

bool QgsPropertyCollectionStack::prepare ( const QgsExpressionContext & context = QgsExpressionContext() ) const

overridevirtual

Prepares the collection against a specified expression context.

Calling prepare before evaluating the collection's properties multiple times allows precalculation of expensive setup tasks such as parsing expressions. Returns true if preparation was successful.

Implements QgsAbstractPropertyCollection.

Definition at line 508 of file qgspropertycollection.cpp.

◆ property()

QgsProperty QgsPropertyCollectionStack::property ( int key ) const

overridevirtual

Returns the highest priority property with a matching key from within the stack.

Parameters

key	integer key for property to return. The intended use case is that a context specific enum is cast to int and used for the key value.

Returns: matching property, or null if no matching, active property found.

See also: hasActiveProperty()

Implements QgsAbstractPropertyCollection.

Definition at line 470 of file qgspropertycollection.cpp.

◆ propertyKeys()

QSet< int > QgsPropertyCollectionStack::propertyKeys ( ) const

overridevirtual

Returns a list of property keys contained within the collection.

Implements QgsAbstractPropertyCollection.

Definition at line 519 of file qgspropertycollection.cpp.

◆ referencedFields()

QSet< QString > QgsPropertyCollectionStack::referencedFields	(	const QgsExpressionContext &	context = `QgsExpressionContext()`,
		bool	ignoreContext = `false`
	)		const

overridevirtual

Returns the set of any fields referenced by the active properties from the stack.

Parameters

context	expression context the properties will be evaluated against.
ignoreContext	This parameter has been added in QGIS 3.14. When set to true, even fields not set in context's fields() will be reported - this is useful e.g. with vector tiles where the actual available field names may not be known beforehand.

Implements QgsAbstractPropertyCollection.

Definition at line 497 of file qgspropertycollection.cpp.

◆ toVariant()

QVariant QgsPropertyCollectionStack::toVariant ( const QgsPropertiesDefinition & definitions ) const

overridevirtual

Saves this property collection to a QVariantMap, wrapped in a QVariant.

You can use QgsXmlUtils::writeVariant to save it to an XML document.

See also: loadVariant()

Implements QgsAbstractPropertyCollection.

Definition at line 541 of file qgspropertycollection.cpp.

◆ value()

QVariant QgsPropertyCollectionStack::value	(	int	key,
		const QgsExpressionContext &	context,
		const QVariant &	defaultValue = `QVariant()`
	)		const

overridevirtual

Returns the calculated value of the highest priority property with the specified key from within the stack.

Parameters

key	integer key for property to calculate. The intended use case is that a context specific enum is cast to int and used for the key value.
context	expression context to evaluate property against
defaultValue	default value to return if no matching, active property found or if the property value cannot be calculated

Returns: calculated property value, or default value if property could not be evaluated

Implements QgsAbstractPropertyCollection.

Definition at line 487 of file qgspropertycollection.cpp.

The documentation for this class was generated from the following files:

/build/qgis-3.14.0+99unstable/src/core/qgspropertycollection.h
/build/qgis-3.14.0+99unstable/src/core/qgspropertycollection.cpp

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ QgsPropertyCollectionStack() [1/2]

◆ ~QgsPropertyCollectionStack()

◆ QgsPropertyCollectionStack() [2/2]

Member Function Documentation

◆ appendCollection()

◆ at() [1/2]

◆ at() [2/2]

◆ clear()

◆ collection()

◆ count()

◆ hasActiveProperties()

◆ hasDynamicProperties()

◆ hasProperty()

◆ isActive()

◆ loadVariant()

◆ operator=()

◆ prepare()

◆ property()

◆ propertyKeys()

◆ referencedFields()

◆ toVariant()

◆ value()