Plasma5Support::DataContainer Class Reference

Inheritance diagram for Plasma5Support::DataContainer:

Signals
void	becameUnused (const QString &source)
void	dataUpdated (const QString &source, const Plasma5Support::DataEngine::Data &data)
void	modelChanged (const QString &source, QAbstractItemModel *model)
void	updateRequested (DataContainer *source)

Public Slots
void	disconnectVisualization (QObject *visualization)
void	forceImmediateUpdate ()

Public Member Functions
	DataContainer (QObject *parent=nullptr)
void	connectVisualization (QObject *visualization, uint pollingInterval, Plasma5Support::Types::IntervalAlignment alignment)
const DataEngine::Data	data () const
DataEngine *	getDataEngine ()
bool	isStorageEnabled () const
bool	isUsed () const
QAbstractItemModel *	model ()
bool	needsToBeStored () const
void	removeAllData ()
void	setData (const QString &key, const QVariant &value)
void	setModel (QAbstractItemModel *model)
void	setNeedsToBeStored (bool store)
void	setStorageEnabled (bool store)
bool	visualizationIsConnected (QObject *visualization) const
Public Member Functions inherited from QObject
	QObject (QObject *parent)
QBindable< QString >	bindableObjectName ()
bool	blockSignals (bool block)
const QObjectList &	children () const const
QMetaObject::Connection	connect (const QObject *sender, const char *signal, const char *method, Qt::ConnectionType type) const const
void	deleteLater ()
void	destroyed (QObject *obj)
bool	disconnect (const char *signal, const QObject *receiver, const char *method) const const
bool	disconnect (const QObject *receiver, const char *method) const const
void	dumpObjectInfo () const const
void	dumpObjectTree () const const
QList< QByteArray >	dynamicPropertyNames () const const
virtual bool	event (QEvent *e)
virtual bool	eventFilter (QObject *watched, QEvent *event)
T	findChild (const QString &name, Qt::FindChildOptions options) const const
QList< T >	findChildren (const QRegularExpression &re, Qt::FindChildOptions options) const const
QList< T >	findChildren (const QString &name, Qt::FindChildOptions options) const const
QList< T >	findChildren (Qt::FindChildOptions options) const const
bool	inherits (const char *className) const const
void	installEventFilter (QObject *filterObj)
bool	isQuickItemType () const const
bool	isWidgetType () const const
bool	isWindowType () const const
void	killTimer (int id)
virtual const QMetaObject *	metaObject () const const
void	moveToThread (QThread *targetThread)
QString	objectName () const const
void	objectNameChanged (const QString &objectName)
QObject *	parent () const const
QVariant	property (const char *name) const const
	Q_CLASSINFO (Name, Value)
	Q_EMIT Q_EMIT
	Q_ENUM (...)
	Q_ENUM_NS (...)
	Q_ENUMS (...)
	Q_FLAG (...)
	Q_FLAG_NS (...)
	Q_FLAGS (...)
	Q_GADGET Q_GADGET
	Q_GADGET_EXPORT (EXPORT_MACRO)
	Q_INTERFACES (...)
	Q_INVOKABLE Q_INVOKABLE
	Q_MOC_INCLUDE Q_MOC_INCLUDE
	Q_NAMESPACE Q_NAMESPACE
	Q_NAMESPACE_EXPORT (EXPORT_MACRO)
	Q_OBJECT Q_OBJECT
	Q_PROPERTY (...)
	Q_REVISION Q_REVISION
	Q_SET_OBJECT_NAME (Object)
	Q_SIGNAL Q_SIGNAL
	Q_SIGNALS Q_SIGNALS
	Q_SLOT Q_SLOT
	Q_SLOTS Q_SLOTS
T	qobject_cast (const QObject *object)
T	qobject_cast (QObject *object)
	QT_NO_NARROWING_CONVERSIONS_IN_CONNECT QT_NO_NARROWING_CONVERSIONS_IN_CONNECT
void	removeEventFilter (QObject *obj)
void	setObjectName (const QString &name)
void	setObjectName (QAnyStringView name)
void	setParent (QObject *parent)
bool	setProperty (const char *name, const QVariant &value)
bool	setProperty (const char *name, QVariant &&value)
bool	signalsBlocked () const const
int	startTimer (int interval, Qt::TimerType timerType)
int	startTimer (std::chrono::milliseconds interval, Qt::TimerType timerType)
QThread *	thread () const const

Protected Slots
void	timerEvent (QTimerEvent *event) override

Protected Member Functions
void	checkForUpdate ()
void	setNeedsUpdate (bool update=true)
uint	timeSinceLastUpdate () const
Protected Member Functions inherited from QObject
virtual void	childEvent (QChildEvent *event)
virtual void	connectNotify (const QMetaMethod &signal)
virtual void	customEvent (QEvent *event)
virtual void	disconnectNotify (const QMetaMethod &signal)
bool	isSignalConnected (const QMetaMethod &signal) const const
int	receivers (const char *signal) const const
QObject *	sender () const const
int	senderSignalIndex () const const
virtual void	timerEvent (QTimerEvent *event)

Additional Inherited Members
Public Types inherited from QObject
typedef	QObjectList
Properties inherited from QObject
	objectName
Static Public Member Functions inherited from QObject
QMetaObject::Connection	connect (const QObject *sender, const char *signal, const QObject *receiver, const char *method, Qt::ConnectionType type)
QMetaObject::Connection	connect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &method, Qt::ConnectionType type)
QMetaObject::Connection	connect (const QObject *sender, PointerToMemberFunction signal, const QObject *context, Functor functor, Qt::ConnectionType type)
QMetaObject::Connection	connect (const QObject *sender, PointerToMemberFunction signal, const QObject *receiver, PointerToMemberFunction method, Qt::ConnectionType type)
QMetaObject::Connection	connect (const QObject *sender, PointerToMemberFunction signal, Functor functor)
bool	disconnect (const QMetaObject::Connection &connection)
bool	disconnect (const QObject *sender, const char *signal, const QObject *receiver, const char *method)
bool	disconnect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &method)
bool	disconnect (const QObject *sender, PointerToMemberFunction signal, const QObject *receiver, PointerToMemberFunction method)
QString	tr (const char *sourceText, const char *disambiguation, int n)

Detailed Description

A set of data exported via a DataEngine.

Plasma5Support::DataContainer wraps the data exported by a DataEngine implementation, providing a generic wrapper for the data.

A DataContainer may have zero or more associated pieces of data which are keyed by strings. The data itself is stored as QVariants. This allows easy and flexible retrieval of the information associated with this object without writing DataContainer or DataEngine specific code in visualizations.

If you are creating your own DataContainer objects (and are passing them to DataEngine::addSource()), you normally just need to listen to the updateRequested() signal (as well as any other methods you might have of being notified of new data) and call setData() to actually update the data. Then you need to either trigger the scheduleSourcesUpdated signal of the parent DataEngine or call checkForUpdate() on the DataContainer.

You also need to set a suitable name for the source with setObjectName(). See DataEngine::addSource() for more information.

Note that there is normally no need to subclass DataContainer, except as a way of encapsulating the data retrieval for a source, since all notifications are done via signals rather than virtual methods.

Definition at line 51 of file datacontainer.h.

Constructor & Destructor Documentation

DataContainer()

Plasma5Support::DataContainer::DataContainer ( QObject * parent = nullptr )

explicit

Constructs a default DataContainer that has no name or data associated with it.

Definition at line 19 of file datacontainer.cpp.

~DataContainer()

Plasma5Support::DataContainer::~DataContainer ( )

override

Definition at line 25 of file datacontainer.cpp.

Member Function Documentation

becameUnused

void Plasma5Support::DataContainer::becameUnused ( const QString & source )

signal

Emitted when the last visualization is disconnected.

Note that if this source was created by DataEngine::sourceRequestEvent(), it will be deleted by DataEngine once control returns to the event loop after this signal is emitted.

Parameters

source

the name of the source that became unused

checkForUpdate()

void Plasma5Support::DataContainer::checkForUpdate ( )

protected

Checks whether any data has changed and, if so, emits dataUpdated().

Definition at line 339 of file datacontainer.cpp.

connectVisualization()

void Plasma5Support::DataContainer::connectVisualization	(	QObject *	visualization,
		uint	pollingInterval,
		Plasma5Support::Types::IntervalAlignment	alignment )

Connects an object to this DataContainer.

May be called repeatedly for the same visualization without side effects

Parameters

visualization	the object to connect to this DataContainer
pollingInterval	the time in milliseconds between updates
alignment	the clock position to align updates to

Definition at line 94 of file datacontainer.cpp.

data()

const DataEngine::Data Plasma5Support::DataContainer::data

(

)

const

Returns the data for this DataContainer.

Definition at line 30 of file datacontainer.cpp.

dataUpdated

void Plasma5Support::DataContainer::dataUpdated ( const QString & source, const Plasma5Support::DataEngine::Data & data )

signal

Emitted when the data has been updated, allowing visualizations to reflect the new data.

Note that you should not normally emit this directly. Instead, use checkForUpdate() or the DataEngine::scheduleSourcesUpdated() slot.

Parameters

source	the objectName() of the DataContainer (and hence the name of the source) that updated its data
data	the updated data

disconnectVisualization

void Plasma5Support::DataContainer::disconnectVisualization ( QObject * visualization )

slot

Disconnects an object from this DataContainer.

Note that if this source was created by DataEngine::sourceRequestEvent(), it will be deleted by DataEngine once control returns to the event loop.

Definition at line 296 of file datacontainer.cpp.

forceImmediateUpdate

void Plasma5Support::DataContainer::forceImmediateUpdate ( )

slot

Forces immediate update signals to all visualizations.

Since

4.4

Definition at line 355 of file datacontainer.cpp.

getDataEngine()

DataEngine * Plasma5Support::DataContainer::getDataEngine

(

)

Returns

the DataEngine that the DataContainer is a child of.

Definition at line 206 of file datacontainer.cpp.

isStorageEnabled()

bool Plasma5Support::DataContainer::isStorageEnabled

(

)

const

Returns

true if the data container has been marked for storage

Since

4.6

Definition at line 191 of file datacontainer.cpp.

isUsed()

bool Plasma5Support::DataContainer::isUsed

(

)

const

Returns

true if one or more visualizations is connected to this DataContainer

Definition at line 377 of file datacontainer.cpp.

model()

QAbstractItemModel * Plasma5Support::DataContainer::model

(

)

Returns

the model owned by this DataSource

Definition at line 72 of file datacontainer.cpp.

modelChanged

void Plasma5Support::DataContainer::modelChanged ( const QString & source, QAbstractItemModel * model )

signal

A new model has been associated to this source, visualizations can safely use it as long they are connected to this source.

Parameters

source	the objectName() of the DataContainer (and hence the name of the source) that owns the model
model	the QAbstractItemModel instance

needsToBeStored()

bool Plasma5Support::DataContainer::needsToBeStored

(

)

const

Returns

true if the data container has been updated, but not stored

Definition at line 196 of file datacontainer.cpp.

removeAllData()

void Plasma5Support::DataContainer::removeAllData

(

)

Removes all data currently associated with this source.

If you call removeAllData() on a DataContainer, you need to either trigger the scheduleSourcesUpdated() slot for the data engine it belongs to or call checkForUpdate() on the DataContainer.

Definition at line 77 of file datacontainer.cpp.

setData()

void Plasma5Support::DataContainer::setData	(	const QString &	key,
		const QVariant &	value )

Set a value for a key.

This also marks this source as needing to signal an update.

If you call setData() directly on a DataContainer, you need to either trigger the scheduleSourcesUpdated() slot for the data engine it belongs to or call checkForUpdate() on the DataContainer.

Parameters

key	a string used as the key for the data
value	a QVariant holding the actual data. If a invalid QVariant is passed in and the key currently exists in the data, then the data entry is removed

Definition at line 35 of file datacontainer.cpp.

setModel()

void Plasma5Support::DataContainer::setModel

(

QAbstractItemModel *

model

)

Associates a model with this DataContainer.

Use this for data that is intended to be a long list of items.

The ownership of the model is transferred to the DataContainer, so the model will be deleted when a new one is set or when the DataContainer itself is deleted, so it will be deleted when there won't be any visualization associated to this source.

Normally you should set the model from DataEngine::setModel instead from here.

Parameters

model

the model that will be associated with this DataContainer

Definition at line 57 of file datacontainer.cpp.

setNeedsToBeStored()

void Plasma5Support::DataContainer::setNeedsToBeStored

(

bool

store

)

sets that the data container needs to be stored or not.

Parameters

whether

the data container needs to be stored

Definition at line 201 of file datacontainer.cpp.

setNeedsUpdate()

void Plasma5Support::DataContainer::setNeedsUpdate ( bool update = true )

protected

Indicates that the data should be treated as dirty the next time hasUpdates() is called.

This is needed for the case where updateRequested() is triggered but we don't want to update the data immediately because it has just been updated. The second request won't be fulfilled in this case, because we never updated the data and so never called checkForUpdate(). So we claim it needs an update anyway.

Definition at line 372 of file datacontainer.cpp.

setStorageEnabled()

void Plasma5Support::DataContainer::setStorageEnabled

(

bool

store

)

sets this data container to be automatically stored.

Parameters

whether

this data container should be stored

Since

4.6

Definition at line 183 of file datacontainer.cpp.

timerEvent

void Plasma5Support::DataContainer::timerEvent ( QTimerEvent * event )

overrideprotectedslot

Reimplemented from superclass. from QObject

Definition at line 389 of file datacontainer.cpp.

timeSinceLastUpdate()

uint Plasma5Support::DataContainer::timeSinceLastUpdate ( ) const

protected

Returns how long ago, in msecs, that the data in this container was last updated.

This is used by DataEngine to compress updates that happen more quickly than the minimum polling interval by calling setNeedsUpdate() instead of calling updateSourceEvent() immediately.

Definition at line 367 of file datacontainer.cpp.

updateRequested

void Plasma5Support::DataContainer::updateRequested ( DataContainer * source )

signal

Emitted when an update is requested.

If a polling interval was passed connectVisualization(), this signal will be emitted every time the interval expires.

Note that if you create your own DataContainer (and pass it to DataEngine::addSource()), you will need to listen to this signal and refresh the data when it is triggered.

Parameters

source

the datacontainer the update was requested for. Useful for classes that update the data for several containers.

visualizationIsConnected()

bool Plasma5Support::DataContainer::visualizationIsConnected

(

QObject *

visualization

)

const

Returns

true if the visualization is currently connected

Definition at line 89 of file datacontainer.cpp.

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

• datacontainer.h
• datacontainer.cpp