QQueue Class▲
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Header: QQueue
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CMake:
find_package(Qt6 REQUIRED COMPONENTS Core)
target_link_libraries(mytarget PRIVATE Qt6::Core)
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qmake: QT += core
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Inherits: QList
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Group: QQueue is part of tools, Implicitly Shared Classes
Detailed Description▲
QQueue<T> is one of Qt's generic container classes. It implements a queue data structure for items of a same type.
A queue is a first in, first out (FIFO) structure. Items are added to the tail of the queue using enqueue() and retrieved from the head using dequeue(). The head() function provides access to the head item without removing it.
Example:
QQueue<int> queue;
queue.enqueue(1);
queue.enqueue(2);
queue.enqueue(3);
while (!queue.isEmpty())
cout << queue.dequeue() << Qt::endl;The example will output 1, 2, 3 in that order.
QQueue inherits from QList. All of QList's functionality also applies to QQueue. For example, you can use isEmpty() to test whether the queue is empty, and you can traverse a QQueue using QList's iterator classes (for example, QListIterator). But in addition, QQueue provides three convenience functions that make it easy to implement FIFO semantics: enqueue(), dequeue(), and head().
QQueue's value type must be an assignable data type. This covers most data types that are commonly used, but the compiler won't let you, for example, store a QWidget as a value. Use QWidget* instead.
See Also▲
Member Function Documentation▲
T QQueue::dequeue()▲
Removes the head item in the queue and returns it. This function assumes that the queue isn't empty.
This is the same as QList::takeFirst().
See Also▲
void QQueue::enqueue(const T &t)▲
T &QQueue::head()▲
Returns a reference to the queue's head item. This function assumes that the queue isn't empty.
This is the same as QList::first().
See Also▲
const T &QQueue::head() const▲
This is an overloaded function.
void QQueue::swap(QQueue<T> &other)▲
Swaps queue other with this queue. This operation is very fast and never fails.