Extends GCF::Component to ease creation of QML components. More...

#include <GCF3/QmlComponent>

Public Member Functions
	QmlComponent (QObject *parent=0)

bool	isActive () const

Q_SIGNAL void	activeChanged (bool val)

QObject *	addQml (const QString &name, const QUrl &url)

QObject *	addQml (const QUrl &url)

Q_INVOKABLE void	addQmlItem (const QString &name, QObject *object)

Q_INVOKABLE void	removeQmlItem (QObject *object)

Q_INVOKABLE void	removeQmlItem (const QString &name)

Q_INVOKABLE QObject *	qmlItem (const QString &name) const

Public Member Functions inherited from GCF::Component
	Component (QObject *parent=0)

virtual QString	name () const

virtual QString	organization () const

virtual GCF::Version	version () const

virtual QString	buildTimestamp () const

const QSettings *	settings () const

bool	isLoaded () const

bool	isActive () const

void	load ()

void	unload ()

void	activate ()

void	deactivate ()

void	addContentObject (const QString &name, QObject *object, const QVariantMap &info=QVariantMap())

void	addContentObject (QObject *object, const QVariantMap &info=QVariantMap())

void	removeContentObject (QObject *object)

void	removeContentObject (const QString &name)

Protected Member Functions
	~QmlComponent ()

void	initializeEvent (GCF::InitializeEvent *e)

void	activationEvent (GCF::ActivationEvent *e)

void	deactivationEvent (GCF::DeactivationEvent *e)

void	contentObjectLoadEvent (GCF::ContentObjectLoadEvent *e)

void	contentObjectMergeEvent (GCF::ContentObjectMergeEvent *e)

void	contentObjectUnloadEvent (GCF::ContentObjectUnloadEvent *e)

void	contentObjectUnmergeEvent (GCF::ContentObjectUnmergeEvent *e)

void	activateContentObjectEvent (GCF::ActivateContentObjectEvent *e)

void	deactivateContentObjectEvent (GCF::DeactivateContentObjectEvent *e)

virtual QObject *	loadQmlObject (const QString &name, const QUrl &url, const QVariantMap &info)

virtual bool	unloadQmlObject (const QString &name, QObject *qmlObject, const QVariantMap &info)

Protected Member Functions inherited from GCF::Component
	~Component ()

virtual void	finalizeEvent (GCF::FinalizeEvent *e)

virtual void	contentLoadEvent (GCF::ContentLoadEvent *e)

virtual void	settingsLoadEvent (GCF::SettingsLoadEvent *e)

virtual void	contentUnloadEvent (GCF::ContentUnloadEvent *e)

virtual void	settingsUnloadEvent (GCF::SettingsUnloadEvent *e)

virtual QObject *	loadObject (const QString &name, const QVariantMap &info)

virtual bool	unloadObject (const QString &name, QObject *object, const QVariantMap &info)

virtual bool	mergeObject (QObject parent, QObject child, const QVariantMap &parentInfo, const QVariantMap &childInfo)

virtual bool	unmergeObject (QObject parent, QObject child, const QVariantMap &parentInfo, const QVariantMap &childInfo)

virtual bool	activateObject (QObject parent, QObject child, const QVariantMap &parentInfo, const QVariantMap &childInfo)

virtual bool	deactivateObject (QObject parent, QObject child, const QVariantMap &parentInfo, const QVariantMap &childInfo)

Detailed Description

This class offers QML friendly methods to make creation of QML components in GCF applications really simple. Please note that there is a difference in the meaning of the term QML-Component when used in Qt 5 context and when used in GCF context. Unless otherwise stated the term QML-Component in this class document refers to an instance of GCF::QmlComponent class.

This class reimplements

GCF::Component::initializeEvent() - to check whether the component is being loaded in a GCF QML application or not. The component asserts a failure and crashes the application otherwise.

GCF::Component::activationEvent() and GCF::Component::deactivationEvent() - to gather changes to component activation and update the active property.

GCF::Component::contentObjectLoadEvent() - to identify qml object kinds and support loading / instantiation of QML objects from .qml files.

GCF::Component::contentObjectMergeEvent() - to ignore merge events for QML objects

GCF::Component::contentObjectUnloadEvent() - to unload QML objects effectively

GCF::Component::contentObjectUnmergeEvent() - to ignore unmerge events for QML objects

GCF::Component::activateContentObjectEvent() - to ignore activation events for QML objects

GCF::Component::deactivateContentObjectEvent() - to ignore deactivation events for QML objects

Content files for QML components can make use of type=qml and url= attributes in object XML element to load QML objects. Example

<content>
    <object name="root" type="qml" url="qrc:///RootItem.qml" >
    <object name="sample" type="qml" url="http://www.something.com/Sample.qml" >
    <object name="another" type="qml" url="file:///Users/jaggesh/Another.qml" >
</content>

Note: QML files loaded using this class, either through content-files or by calling the addQml() function, can make use of a gComponent object in their code to reference this component.

This class also offers a specialized virtual function called loadQmlObject(), whose default implementation eases out loading of QML objects from .qml files. Subclasses can reimplement this function to customize the loading of QML objects.

The addQml() methods may be used to add QML objects from .qml files - without loading them from the content-file. Custom QML items can be added using addQmlItem() method. QML items added using addQml() or addQmlItem() methods are included in the object list.

Note: This class is available only if GCF is compiled and linked against Qt 5.

Constructor & Destructor Documentation

GCF::QmlComponent::QmlComponent ( QObject * parent = 0 )

Constructor. Creates an instance of this class and inserts it as a child under parent.

Note: It is recommended that subclasses of GCF::GuiComponent declare their constructor as public and destructor as protected. This will ensure that the components are created on the heap always.

GCF::QmlComponent::~QmlComponent ( )

protected

Destructor.

Note: It is recommended that subclasses of GCF::GuiComponent declare their constructor as public and destructor as protected. This will ensure that the components are created on the heap always.

Member Function Documentation

bool GCF::QmlComponent::isActive ( ) const

Returns true if the component has been activated. False otherwise.

This function is called when the active property is READ. The active property is notified as changed whenever this component receives a activationEvent() or deactivationEvent(). Change notifications to this property are signaled using the activeChanged() signal.

void GCF::QmlComponent::activeChanged ( bool val )

This signal is emitted whenever the active property changes.

QObject * GCF::QmlComponent::addQml	(	const QString &	name,
		const QUrl &	url
	)

This function can be used to create a QML object from url and add it as a content-object of this component.

Parameters

name	name to be set on QML object loaded from `url`.
url	location of the .qml file from which the QML object should be loaded. `http`, `file`, `ftp` and `qrc` schemes are supported.

Returns: pointer to the loaded QML object upon success, null upon failure.

Note: QML objects added using this function can access a gComponent object in their code to access methods on this component.

See Also: GCF::Component::addContentObject()

QObject * GCF::QmlComponent::addQml ( const QUrl & url )

This function adds a QML object from url.

Parameters

url	location of the .qml file from which the QML object should be loaded. `http`, `file`, `ftp` and `qrc` schemes are supported.

Returns: pointer to the loaded QML object upon success, null upon failure.

Name of the QML object is inferred from the file-name of the .qml file specified in url.

Note: QML objects added using this function can access a gComponent object in their code to access methods on this component.

void GCF::QmlComponent::addQmlItem	(	const QString &	name,
		QObject *	object
	)

Adds a QML item as content object to this component

Parameters

name	name of the QML object
object	pointer to the QML object

Note: This function can be called from within QML code using gComponent.addQmlItem(string,object)

void GCF::QmlComponent::removeQmlItem ( QObject * object )

Removes a QML item as content object from this component

Parameters

object pointer to the QML object that needs to be removed

Note: This function can be called from within QML code using gComponent.removeQmlItem(object)

void GCF::QmlComponent::removeQmlItem ( const QString & name )

Removes a QML item as content object from this component

Parameters

name	name of the QML object that needs to be removed

Note: This function can be called from within QML code using gComponent.removeQmlItem(string)

QObject * GCF::QmlComponent::qmlItem ( const QString & name ) const

Returns pointer to a QML object (or item) whose name is name. For this function to work a QML object should have been added using addQmlItem() for the same name before.

Parameters

name	name of the QML item/object to return

Returns: pointer to the QML object. NULL if no such object was found.

Note: This function can be called from within QML code using gComponent.qmlItem(string)

void GCF::QmlComponent::initializeEvent ( GCF::InitializeEvent * e )

protectedvirtual

This event handler is implemented to ASSERT crash the application, if the component is attempted for loading within a non QML application. It calls the base class implementation of the event handler otherwise.

Reimplemented from GCF::Component.

void GCF::QmlComponent::activationEvent ( GCF::ActivationEvent * e )

protectedvirtual

Updates the active property and calls the base class implementation of this event handler

Reimplemented from GCF::Component.

void GCF::QmlComponent::deactivationEvent ( GCF::DeactivationEvent * e )

protectedvirtual

Updates the active property and calls the base class implementation of this event handler

Reimplemented from GCF::Component.

void GCF::QmlComponent::contentObjectLoadEvent ( GCF::ContentObjectLoadEvent * e )

protectedvirtual

This event handler is implemented to look for a type key in the information map (GCF::ContentObjectLoadEvent::info()) provided by the event-object. If the type is qml, then it looks for a url key in the information map and loads the .qml file specified in url using the loadQmlObject() method.

If the type key is not qml, then the base class implementation of this event handler is called; which in turn calls the loadObject() method.

Reimplemented from GCF::Component.

void GCF::QmlComponent::contentObjectMergeEvent ( GCF::ContentObjectMergeEvent * e )

protectedvirtual

This event hanlder is implemented to ignore merge events for QML objects

Reimplemented from GCF::Component.

void GCF::QmlComponent::contentObjectUnloadEvent ( GCF::ContentObjectUnloadEvent * e )

protectedvirtual

This event handler is implemented to look for a type key in the information map (GCF::ContentObjectLoadEvent::info()) provided by the event-object. If the type is qml, then it calls the unloadQmlObject() method to unload the QML object.

If the type key is not qml, then the base class implementation of this event handler is called; which in turn calls the unloadObject() method.

Reimplemented from GCF::Component.

void GCF::QmlComponent::contentObjectUnmergeEvent ( GCF::ContentObjectUnmergeEvent * e )

protectedvirtual

This event hanlder is implemented to ignore unmerge events for QML objects

Reimplemented from GCF::Component.

void GCF::QmlComponent::activateContentObjectEvent ( GCF::ActivateContentObjectEvent * e )

protectedvirtual

This event hanlder is implemented to ignore activation events for QML objects

Reimplemented from GCF::Component.

void GCF::QmlComponent::deactivateContentObjectEvent ( GCF::DeactivateContentObjectEvent * e )

protectedvirtual

This event hanlder is implemented to ignore deactivation events for QML objects

Reimplemented from GCF::Component.

QObject * GCF::QmlComponent::loadQmlObject	(	const QString &	name,
		const QUrl &	url,
		const QVariantMap &	info
	)

protectedvirtual

This function can be implemented to customize the loading a QML object from url. The default implementation loads the QML file at URL and returns a pointer to it. The default implementation also ensures that a gComponent object is available in the QML code that offers access to this component class.

Parameters

name	name of the QML object that needs to be loaded
url	URL from which the QML file needs to be loaded. If you reimplement this function you must ensure that `http`, `ftp`, `qrc` and `file` URL schemes are fully supported.
info	key=value information map associated with the QML object that needs to be loaded

Returns: pointer to the QML object that was loaded.

bool GCF::QmlComponent::unloadQmlObject	(	const QString &	name,
		QObject *	qmlObject,
		const QVariantMap &	info
	)

protectedvirtual

This function can be implemented to customize the unloading of a QML object. The default implementation simply deletes the QML object.

Parameters

name	name of the QML object that needs to be unloaded
qmlObject	pointer to the QMl object that needs to be unloaded
info	key=value information map associated with the QML object that needs to be unloaded

Returns: true on successful unloading of the object, false otherwise. The default implemnetation always returns true.

Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation