IdentifiantMot de passe
Loading...
Mot de passe oublié ?Je m'inscris ! (gratuit)

QtConcurrent Namespace

The QtConcurrent namespace provides high-level APIs that make it possible to write multi-threaded programs without using low-level threading primitives.

Article lu   fois.

L'auteur

Liens sociaux

Viadeo Twitter Facebook Share on Google+   

QtConcurrent Namespace

  • Header: QtConcurrent

  • CMake:

    find_package(Qt6 REQUIRED COMPONENTS Concurrent)

    target_link_libraries(mytarget PRIVATE Qt6::Concurrent)

  • qmake: QT += concurrent

  • Group: QtConcurrent is part of thread

Detailed Description

See the Qt Concurrent module documentation for an overview of available functions, or see below for detailed information on each function.

Classes

 

class QTaskBuilder

The QTaskBuilder class is used for adjusting task parameters.

Type Documentation

 

enum QtConcurrent::FutureResult

This enum type is used to invoke a special overload of QtConcurrent::QTaskBuilder::spawn(QtConcurrent::FutureResult) that doesn't return a future object.

Constant

Value

Description

QtConcurrent::FutureResult::Ignore

0

An auxiliary tag which introduced to improve code readability.

[alias] InvokeResultType

The simplified definition of this type looks like this:

 
Sélectionnez
template <class Task, class ...Args>
using InvokeResultType = std::invoke_result_t<std::decay_t<Task>, std::decay_t<Args>...>;

The real implementation also contains a compile-time check for whether the task can be invoked with the specified arguments or not.

enum QtConcurrent::ReduceOption

flags QtConcurrent::ReduceOptions

This enum specifies the order of which results from the map or filter function are passed to the reduce function.

Constant

Value

Description

QtConcurrent::UnorderedReduce

0x1

Reduction is done in an arbitrary order.

QtConcurrent::OrderedReduce

0x2

Reduction is done in the order of the original sequence.

QtConcurrent::SequentialReduce

0x4

Reduction is done sequentially: only one thread will enter the reduce function at a time. (Parallel reduction might be supported in a future version of Qt Concurrent.)

The ReduceOptions type is a typedef for QFlags<ReduceOption>. It stores an OR combination of ReduceOption values.

Function Documentation

 

void QtConcurrent::blockingFilter(QThreadPool *pool, Sequence &sequence, KeepFunctor &&filterFunction)

Calls filterFunction once for each item in sequence. All calls to filterFunction are invoked from the threads taken from the QThreadPool pool. If filterFunction returns true, the item is kept in sequence; otherwise, the item is removed from sequence.

Note that this method doesn't have an overload working with iterators, because it invalidates the iterators of the sequence it operates on.

This function will block until all items in the sequence have been processed.

See Also

void QtConcurrent::blockingFilter(Sequence &sequence, KeepFunctor &&filterFunction)

Calls filterFunction once for each item in sequence. If filterFunction returns true, the item is kept in sequence; otherwise, the item is removed from sequence.

Note that this method doesn't have an overload working with iterators, because it invalidates the iterators of the sequence it operates on.

This function will block until all items in the sequence have been processed.

See Also

std::decay_t<Sequence> QtConcurrent::blockingFiltered(QThreadPool *pool, Sequence &&sequence, KeepFunctor &&filterFunction)

Calls filterFunction once for each item in sequence and returns a new Sequence of kept items. All calls to filterFunction are invoked from the threads taken from the QThreadPool pool. If filterFunction returns true, a copy of the item is put in the new Sequence. Otherwise, the item will not appear in the new Sequence.

This function will block until all items in the sequence have been processed.

See Also

std::decay_t<Sequence> QtConcurrent::blockingFiltered(Sequence &&sequence, KeepFunctor &&filterFunction)

Calls filterFunction once for each item in sequence and returns a new Sequence of kept items. If filterFunction returns true, a copy of the item is put in the new Sequence. Otherwise, the item will not appear in the new Sequence.

This function will block until all items in the sequence have been processed.

See Also

OutputSequence QtConcurrent::blockingFiltered(QThreadPool *pool, Iterator begin, Iterator end, KeepFunctor &&filterFunction)

Calls filterFunction once for each item from begin to end and returns a new Sequence of kept items. All calls to filterFunction are invoked from the threads taken from the QThreadPool pool. If filterFunction returns true, a copy of the item is put in the new Sequence. Otherwise, the item will not appear in the new Sequence.

This function will block until the iterator reaches the end of the sequence being processed.

See Also

OutputSequence QtConcurrent::blockingFiltered(Iterator begin, Iterator end, KeepFunctor &&filterFunction)

Calls filterFunction once for each item from begin to end and returns a new Sequence of kept items. If filterFunction returns true, a copy of the item is put in the new Sequence. Otherwise, the item will not appear in the new Sequence.

This function will block until the iterator reaches the end of the sequence being processed.

See Also

ResultType QtConcurrent::blockingFilteredReduced(QThreadPool *pool, Sequence &&sequence, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item in sequence. All calls to filterFunction are invoked from the threads taken from the QThreadPool pool. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, reduceFunction is called in the order of the original sequence.

This function will block until all items in the sequence have been processed.

See Also

ResultType QtConcurrent::blockingFilteredReduced(Sequence &&sequence, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item in sequence. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, reduceFunction is called in the order of the original sequence.

This function will block until all items in the sequence have been processed.

See Also

ResultType QtConcurrent::blockingFilteredReduced(QThreadPool *pool, Sequence &&sequence, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item in sequence. All calls to filterFunction are invoked from the threads taken from the QThreadPool pool. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, reduceFunction is called in the order of the original sequence.

This function will block until all items in the sequence have been processed.

See Also

ResultType QtConcurrent::blockingFilteredReduced(Sequence &&sequence, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item in sequence. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, reduceFunction is called in the order of the original sequence.

This function will block until all items in the sequence have been processed.

See Also

ResultType QtConcurrent::blockingFilteredReduced(QThreadPool *pool, Iterator begin, Iterator end, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item from begin to end. All calls to filterFunction are invoked from the threads taken from the QThreadPool pool. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, the reduceFunction is called in the order of the original sequence.

This function will block until the iterator reaches the end of the sequence being processed.

See Also

ResultType QtConcurrent::blockingFilteredReduced(Iterator begin, Iterator end, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item from begin to end. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, the reduceFunction is called in the order of the original sequence.

This function will block until the iterator reaches the end of the sequence being processed.

See Also

ResultType QtConcurrent::blockingFilteredReduced(QThreadPool *pool, Iterator begin, Iterator end, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item from begin to end. All calls to filterFunction are invoked from the threads taken from the QThreadPool pool. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, the reduceFunction is called in the order of the original sequence.

This function will block until the iterator reaches the end of the sequence being processed.

See Also

ResultType QtConcurrent::blockingFilteredReduced(Iterator begin, Iterator end, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item from begin to end. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, the reduceFunction is called in the order of the original sequence.

This function will block until the iterator reaches the end of the sequence being processed.

See Also

void QtConcurrent::blockingMap(QThreadPool *pool, Sequence &&sequence, MapFunctor function)

Calls function once for each item in sequence. All calls to function are invoked from the threads taken from the QThreadPool pool. The function takes a reference to the item, so that any modifications done to the item will appear in sequence.

This function will block until all items in the sequence have been processed.

See Also

void QtConcurrent::blockingMap(Sequence &&sequence, MapFunctor &&function)

Calls function once for each item in sequence. The function takes a reference to the item, so that any modifications done to the item will appear in sequence.

This function will block until all items in the sequence have been processed.

See Also

void QtConcurrent::blockingMap(QThreadPool *pool, Iterator begin, Iterator end, MapFunctor &&function)

Calls function once for each item from begin to end. All calls to function are invoked from the threads taken from the QThreadPool pool. The function takes a reference to the item, so that any modifications done to the item will appear in the sequence which the iterators belong to.

This function will block until the iterator reaches the end of the sequence being processed.

See Also

void QtConcurrent::blockingMap(Iterator begin, Iterator end, MapFunctor &&function)

Calls function once for each item from begin to end. The function takes a reference to the item, so that any modifications done to the item will appear in the sequence which the iterators belong to.

This function will block until the iterator reaches the end of the sequence being processed.

See Also

OutputSequence QtConcurrent::blockingMapped(QThreadPool *pool, InputSequence &&sequence, MapFunctor &&function)

Calls function once for each item in sequence and returns an OutputSequence containing the results. All calls to function are invoked from the threads taken from the QThreadPool pool. The type of the results will match the type returned by the MapFunctor.

This function will block until all items in the sequence have been processed.

See Also

OutputSequence QtConcurrent::blockingMapped(InputSequence &&sequence, MapFunctor &&function)

Calls function once for each item in sequence and returns an OutputSequence containing the results. The type of the results will match the type returned by the MapFunctor.

This function will block until all items in the sequence have been processed.

See Also

Sequence QtConcurrent::blockingMapped(QThreadPool *pool, Iterator begin, Iterator end, MapFunctor &&function)

Calls function once for each item from begin to end and returns a container with the results. All calls to function are invoked from the threads taken from the QThreadPool pool. You can specify the type of container as the a template argument, like this:

 
Sélectionnez
QList&lt;int&gt; ints = QtConcurrent::blockingMapped&lt;QList&lt;int&gt; &gt;(beginIterator, endIterator, fn);

This function will block until the iterator reaches the end of the sequence being processed.

See Also

Sequence QtConcurrent::blockingMapped(Iterator begin, Iterator end, MapFunctor &&function)

Calls function once for each item from begin to end and returns a container with the results. You can specify the type of container as the a template argument, like this:

 
Sélectionnez
QList&lt;int&gt; ints = QtConcurrent::blockingMapped&lt;QList&lt;int&gt; &gt;(beginIterator, endIterator, fn);

This function will block until the iterator reaches the end of the sequence being processed.

See Also

ResultType QtConcurrent::blockingMappedReduced(QThreadPool *pool, Sequence &&sequence, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item in sequence. All calls to mapFunction are invoked from the threads taken from the QThreadPool pool. The return value of each mapFunction is passed to reduceFunction.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is determined by reduceOptions.

This function will block until all items in the sequence have been processed.

See Also

ResultType QtConcurrent::blockingMappedReduced(Sequence &&sequence, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item in sequence. The return value of each mapFunction is passed to reduceFunction.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is determined by reduceOptions.

This function will block until all items in the sequence have been processed.

See Also

ResultType QtConcurrent::blockingMappedReduced(QThreadPool *pool, Sequence &&sequence, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item in sequence. All calls to mapFunction are invoked from the threads taken from the QThreadPool pool. The return value of each mapFunction is passed to reduceFunction. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is determined by reduceOptions.

This function will block until all items in the sequence have been processed.

See Also

ResultType QtConcurrent::blockingMappedReduced(Sequence &&sequence, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item in sequence. The return value of each mapFunction is passed to reduceFunction. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is determined by reduceOptions.

This function will block until all items in the sequence have been processed.

See Also

ResultType QtConcurrent::blockingMappedReduced(QThreadPool *pool, Iterator begin, Iterator end, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item from begin to end. All calls to mapFunction are invoked from the threads taken from the QThreadPool pool. The return value of each mapFunction is passed to reduceFunction.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined.

This function will block until the iterator reaches the end of the sequence being processed.

See Also

ResultType QtConcurrent::blockingMappedReduced(Iterator begin, Iterator end, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item from begin to end. The return value of each mapFunction is passed to reduceFunction.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined.

This function will block until the iterator reaches the end of the sequence being processed.

See Also

ResultType QtConcurrent::blockingMappedReduced(QThreadPool *pool, Iterator begin, Iterator end, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item from begin to end. All calls to mapFunction are invoked from the threads taken from the QThreadPool pool. The return value of each mapFunction is passed to reduceFunction. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined.

This function will block until the iterator reaches the end of the sequence being processed.

See Also

ResultType QtConcurrent::blockingMappedReduced(Iterator begin, Iterator end, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item from begin to end. The return value of each mapFunction is passed to reduceFunction. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined.

This function will block until the iterator reaches the end of the sequence being processed.

See Also

QFuture<void> QtConcurrent::filter(QThreadPool *pool, Sequence &sequence, KeepFunctor &&filterFunction)

Calls filterFunction once for each item in sequence. All calls to filterFunction are invoked from the threads taken from the QThreadPool pool. If filterFunction returns true, the item is kept in sequence; otherwise, the item is removed from sequence.

Note that this method doesn't have an overload working with iterators, because it invalidates the iterators of the sequence it operates on.

See Also

QFuture<void> QtConcurrent::filter(Sequence &sequence, KeepFunctor &&filterFunction)

Calls filterFunction once for each item in sequence. If filterFunction returns true, the item is kept in sequence; otherwise, the item is removed from sequence.

Note that this method doesn't have an overload working with iterators, because it invalidates the iterators of the sequence it operates on.

See Also

QFuture<typename std::decay_t<Sequence>::value_type> QtConcurrent::filtered(QThreadPool *pool, Sequence &&sequence, KeepFunctor &&filterFunction)

Calls filterFunction once for each item in sequence and returns a new Sequence of kept items. All calls to filterFunction are invoked from the threads taken from the QThreadPool pool. If filterFunction returns true, a copy of the item is put in the new Sequence. Otherwise, the item will not appear in the new Sequence.

See Also

QFuture<typename std::decay_t<Sequence>::value_type> QtConcurrent::filtered(Sequence &&sequence, KeepFunctor &&filterFunction)

Calls filterFunction once for each item in sequence and returns a new Sequence of kept items. If filterFunction returns true, a copy of the item is put in the new Sequence. Otherwise, the item will not appear in the new Sequence.

See Also

QFuture<typename qValueType<Iterator>::value_type> QtConcurrent::filtered(QThreadPool *pool, Iterator begin, Iterator end, KeepFunctor &&filterFunction)

Calls filterFunction once for each item from begin to end and returns a new Sequence of kept items. All calls to filterFunction are invoked from the threads taken from the QThreadPool pool. If filterFunction returns true, a copy of the item is put in the new Sequence. Otherwise, the item will not appear in the new Sequence.

See Also

QFuture<typename qValueType<Iterator>::value_type> QtConcurrent::filtered(Iterator begin, Iterator end, KeepFunctor &&filterFunction)

Calls filterFunction once for each item from begin to end and returns a new Sequence of kept items. If filterFunction returns true, a copy of the item is put in the new Sequence. Otherwise, the item will not appear in the new Sequence.

See Also

QFuture<ResultType> QtConcurrent::filteredReduced(QThreadPool *pool, Sequence &&sequence, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item in sequence. All calls to filterFunction are invoked from the threads taken from the QThreadPool pool. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, reduceFunction is called in the order of the original sequence.

See Also

QFuture<ResultType> QtConcurrent::filteredReduced(Sequence &&sequence, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item in sequence. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, reduceFunction is called in the order of the original sequence.

See Also

QFuture<ResultType> QtConcurrent::filteredReduced(QThreadPool *pool, Sequence &&sequence, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item in sequence. All calls to filterFunction are invoked from the threads taken from the QThreadPool pool. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, reduceFunction is called in the order of the original sequence.

See Also

QFuture<ResultType> QtConcurrent::filteredReduced(Sequence &&sequence, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item in sequence. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, reduceFunction is called in the order of the original sequence.

See Also

QFuture<ResultType> QtConcurrent::filteredReduced(QThreadPool *pool, Iterator begin, Iterator end, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item from begin to end. All calls to filterFunction are invoked from the threads taken from the QThreadPool pool. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, the reduceFunction is called in the order of the original sequence.

See Also

QFuture<ResultType> QtConcurrent::filteredReduced(Iterator begin, Iterator end, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item from begin to end. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, the reduceFunction is called in the order of the original sequence.

See Also

QFuture<ResultType> QtConcurrent::filteredReduced(QThreadPool *pool, Iterator begin, Iterator end, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item from begin to end. All calls to filterFunction are invoked from the threads taken from the QThreadPool pool. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, the reduceFunction is called in the order of the original sequence.

See Also

QFuture<ResultType> QtConcurrent::filteredReduced(Iterator begin, Iterator end, KeepFunctor &&filterFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls filterFunction once for each item from begin to end. If filterFunction returns true for an item, that item is then passed to reduceFunction. In other words, the return value is the result of reduceFunction for each item where filterFunction returns true. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while filterFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is undefined if reduceOptions is QtConcurrent::UnorderedReduce. If reduceOptions is QtConcurrent::OrderedReduce, the reduceFunction is called in the order of the original sequence.

See Also

QFuture<void> QtConcurrent::map(QThreadPool *pool, Sequence &&sequence, MapFunctor &&function)

Calls function once for each item in sequence. All calls to function are invoked from the threads taken from the QThreadPool pool. The function takes a reference to the item, so that any modifications done to the item will appear in sequence.

See Also

QFuture<void> QtConcurrent::map(Sequence &&sequence, MapFunctor &&function)

Calls function once for each item in sequence. The function takes a reference to the item, so that any modifications done to the item will appear in sequence.

See Also

QFuture<void> QtConcurrent::map(QThreadPool *pool, Iterator begin, Iterator end, MapFunctor &&function)

Calls function once for each item from begin to end. All calls to function are invoked from the threads taken from the QThreadPool pool. The function takes a reference to the item, so that any modifications done to the item will appear in the sequence which the iterators belong to.

See Also

QFuture<void> QtConcurrent::map(Iterator begin, Iterator end, MapFunctor &&function)

Calls function once for each item from begin to end. The function takes a reference to the item, so that any modifications done to the item will appear in the sequence which the iterators belong to.

See Also

QFuture<QtPrivate::MapResultType<Sequence, MapFunctor>> QtConcurrent::mapped(QThreadPool *pool, Sequence &&sequence, MapFunctor &&function)

Calls function once for each item in sequence and returns a future with each mapped item as a result. All calls to function are invoked from the threads taken from the QThreadPool pool. You can use QFuture::const_iterator or QFutureIterator to iterate through the results.

See Also

QFuture<QtPrivate::MapResultType<Sequence, MapFunctor>> QtConcurrent::mapped(Sequence &&sequence, MapFunctor &&function)

Calls function once for each item in sequence and returns a future with each mapped item as a result. You can use QFuture::const_iterator or QFutureIterator to iterate through the results.

See Also

QFuture<QtPrivate::MapResultType<Iterator, MapFunctor>> QtConcurrent::mapped(QThreadPool *pool, Iterator begin, Iterator end, MapFunctor &&function)

Calls function once for each item from begin to end and returns a future with each mapped item as a result. All calls to function are invoked from the threads taken from the QThreadPool pool. You can use QFuture::const_iterator or QFutureIterator to iterate through the results.

See Also

QFuture<QtPrivate::MapResultType<Iterator, MapFunctor>> QtConcurrent::mapped(Iterator begin, Iterator end, MapFunctor &&function)

Calls function once for each item from begin to end and returns a future with each mapped item as a result. You can use QFuture::const_iterator or QFutureIterator to iterate through the results.

See Also

QFuture<ResultType> QtConcurrent::mappedReduced(QThreadPool *pool, Sequence &&sequence, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item in sequence. All calls to mapFunction are invoked from the threads taken from the QThreadPool pool. The return value of each mapFunction is passed to reduceFunction.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is determined by reduceOptions.

See Also

QFuture<ResultType> QtConcurrent::mappedReduced(Sequence &&sequence, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item in sequence. The return value of each mapFunction is passed to reduceFunction.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is determined by reduceOptions.

See Also

QFuture<ResultType> QtConcurrent::mappedReduced(QThreadPool *pool, Sequence &&sequence, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item in sequence. All calls to mapFunction are invoked from the threads taken from the QThreadPool pool. The return value of each mapFunction is passed to reduceFunction. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is determined by reduceOptions.

See Also

QFuture<ResultType> QtConcurrent::mappedReduced(Sequence &&sequence, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item in sequence. The return value of each mapFunction is passed to reduceFunction. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. The order in which reduceFunction is called is determined by reduceOptions.

See Also

QFuture<ResultType> QtConcurrent::mappedReduced(QThreadPool *pool, Iterator begin, Iterator end, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item from begin to end. All calls to mapFunction are invoked from the threads taken from the QThreadPool pool. The return value of each mapFunction is passed to reduceFunction.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. By default, the order in which reduceFunction is called is undefined.

QtConcurrent::OrderedReduce results in the ordered reduction.

See Also

QFuture<ResultType> QtConcurrent::mappedReduced(Iterator begin, Iterator end, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item from begin to end. The return value of each mapFunction is passed to reduceFunction.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. By default, the order in which reduceFunction is called is undefined.

QtConcurrent::OrderedReduce results in the ordered reduction.

See Also

QFuture<ResultType> QtConcurrent::mappedReduced(QThreadPool *pool, Iterator begin, Iterator end, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item from begin to end. All calls to mapFunction are invoked from the threads taken from the QThreadPool pool. The return value of each mapFunction is passed to reduceFunction. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. By default, the order in which reduceFunction is called is undefined.

QtConcurrent::OrderedReduce results in the ordered reduction.

See Also

QFuture<ResultType> QtConcurrent::mappedReduced(Iterator begin, Iterator end, MapFunctor &&mapFunction, ReduceFunctor &&reduceFunction, InitialValueType &&initialValue, QtConcurrent::ReduceOptions reduceOptions = ReduceOptions(UnorderedReduce | SequentialReduce))

Calls mapFunction once for each item from begin to end. The return value of each mapFunction is passed to reduceFunction. The result value is initialized to initialValue when the function is called, and the first call to reduceFunction will operate on this value.

Note that while mapFunction is called concurrently, only one thread at a time will call reduceFunction. By default, the order in which reduceFunction is called is undefined.

QtConcurrent::OrderedReduce results in the ordered reduction.

See Also

QFuture<T> QtConcurrent::run(Function function, ...)

Equivalent to

 
Sélectionnez
QtConcurrent::run(QThreadPool::globalInstance(), function, ...);

Runs function in a separate thread. The thread is taken from the global QThreadPool. Note that function may not run immediately; function will only be run once a thread becomes available.

In basic mode T is the same type as the return value of function. Non-void return values can be accessed via the QFuture::result() function.

In basic mode the QFuture returned can only be used to query for the running/finished status and the return value of the function. In particular, canceling or pausing can be issued only if the computations behind the future has not been started.

In run with promise mode, the function is expected to return void and must take an additional argument of QPromise<T> & type, placed as a first argument in function's argument list. T is the result type and it is the same for the returned QFuture<T>.

In run with promise mode, similar to basic mode, the QFuture returned can be used to query for the running/finished status and the value reported by the function. In addition, it may be used for suspending or canceling the running task, fetching multiple results from the called function or monitoring progress reported by the function.

See Also

[since 5.4] QFuture<T> QtConcurrent::run(QThreadPool *pool, Function function, ...)

Runs function in a separate thread. The thread is taken from the QThreadPool pool. Note that function may not run immediately; function will only be run once a thread becomes available.

In basic mode T is the same type as the return value of function. Non-void return values can be accessed via the QFuture::result() function.

In basic mode the QFuture returned can only be used to query for the running/finished status and the return value of the function. In particular, canceling or pausing can be issued only if the computations behind the future has not been started.

In run with promise mode, the function is expected to return void and must take an additional argument of QPromise<T> & type, placed as a first argument in function's argument list. T is the result type and it is the same for the returned QFuture<T>.

In run with promise mode, similar to basic mode, the QFuture returned can be used to query for the running/finished status and the value reported by the function. In addition, it may be used for suspending or canceling the running task, fetching multiple results from the called function or monitoring progress reported by the function.

This function was introduced in Qt 5.4.

See Also

[since 6.0] QTaskBuilder<Task> QtConcurrent::task(Task &&task)

Creates an instance of QtConcurrent::QTaskBuilder. This object can be used to adjust some parameters and run task in a separate thread.

This function was introduced in Qt 6.0.

See Also

Vous avez aimé ce tutoriel ? Alors partagez-le en cliquant sur les boutons suivants : Viadeo Twitter Facebook Share on Google+