The QFutureSynchronizer class is a convenience class that simplifies QFuture synchronization. More...

Public Methods
	QFutureSynchronizer ()

	QFutureSynchronizer (const QFuture< T > &future)

	~QFutureSynchronizer ()

void	addFuture (const QFuture< T > &future)

bool	cancelOnWait () const

void	clearFutures ()

QList< QFuture< T > >	futures () const

void	setCancelOnWait (bool enabled)

void	setFuture (const QFuture< T > &future)

void	waitForFinished ()

Detailed Description

template<typename T>
class QFutureSynchronizer< T >

The QFutureSynchronizer class is a convenience class that simplifies QFuture synchronization.

QFutureSynchronizer is a template class that simplifies synchronization of one or more QFuture objects. Futures are added using the addFuture() or setFuture() functions. The futures() function returns a list of futures. Use clearFutures() to remove all futures from the QFutureSynchronizer.

The waitForFinished() function waits for all futures to finish. The destructor of QFutureSynchronizer calls waitForFinished(), providing an easy way to ensure that all futures have finished before returning from a function:

void someFunction()
{
    QFutureSynchronizer<void> synchronizer;
 
    ...
 
    synchronizer.addFuture(QtConcurrent::run(anotherFunction));
    synchronizer.addFuture(QtConcurrent::map(list, mapFunction));
 
    return; // QFutureSynchronizer waits for all futures to finish
}

The behavior of waitForFinished() can be changed using the setCancelOnWait() function. Calling setCancelOnWait(true) will cause waitForFinished() to cancel all futures before waiting for them to finish. You can query the status of the cancel-on-wait feature using the cancelOnWait() function.

See also: QFuture, QFutureWatcher, Concurrent Programming

Constructor & Destructor Documentation

template<typename T >

QFutureSynchronizer< T >::QFutureSynchronizer ( )

inline

Constructs a QFutureSynchronizer.

template<typename T >

QFutureSynchronizer< T >::QFutureSynchronizer ( const QFuture< T > & future )

inlineexplicit

Constructs a QFutureSynchronizer and begins watching future by calling addFuture().

See also: addFuture()

template<typename T >

QFutureSynchronizer< T >::~QFutureSynchronizer ( )

inline

Calls waitForFinished() function to ensure that all futures have finished before destroying this QFutureSynchronizer.

See also: waitForFinished()

Method Documentation

template<typename T >

void QFutureSynchronizer< T >::addFuture ( const QFuture< T > & future )

inline

Adds future to the list of managed futures.

See also: futures()

template<typename T >

bool QFutureSynchronizer< T >::cancelOnWait ( ) const

inline

Returns true if the cancel-on-wait feature is enabled, otherwise returns false. If cancel-on-wait is enabled, the waitForFinished() function will cancel all futures before waiting for them to finish.

See also: setCancelOnWait(), waitForFinished()

template<typename T >

void QFutureSynchronizer< T >::clearFutures ( )

inline

Removes all managed futures from this QFutureSynchronizer.

See also: addFuture(), setFuture()

template<typename T >

QList< QFuture< T > > QFutureSynchronizer< T >::futures ( ) const

inline

Returns a list of all managed futures.

See also: addFuture(), setFuture()

template<typename T >

void QFutureSynchronizer< T >::setCancelOnWait ( bool enabled )

inline

Enables or disables the cancel-on-wait feature based on the enabled argument. If enabled is true, the waitForFinished() function will cancel all futures before waiting for them to finish.

See also: cancelOnWait(), waitForFinished()

template<typename T >

void QFutureSynchronizer< T >::setFuture ( const QFuture< T > & future )

inline

Sets future to be the only future managed by this QFutureSynchronizer. This method calls waitForFinished(), clearFutures(), and finally passes the given future to addFuture().

See also: addFuture(), waitForFinished(), clearFutures()

template<typename T >

void QFutureSynchronizer< T >::waitForFinished ( )

inline

Waits for all futures to finish. If cancelOnWait() returns true, each future is canceled before waiting for them to finish.

See also: cancelOnWait(), setCancelOnWait()

Public Methods

Detailed Description

template<typename T> class QFutureSynchronizer< T >

Constructor & Destructor Documentation

Method Documentation

template<typename T>
class QFutureSynchronizer< T >