Qt 6 是努力使框架更高效，且更易于使用的结果。
为兼容每个发行的所有公共 API，我们试着维护二进制和源代码。但是，为使 Qt 成为更优框架，一些改变是不可避免的。
在此话题中，我们汇总了那些 Qt Concurrent 变化，并提供处理它们的指导。
QtConcurrent::run() has been improved to work with a variable number of arguments, so the signatures are changed to:
// run template <typename T> QFuture<T> run(Function &&f, Args &&...args) // run with a QThreadPool argument template <typename T> QFuture<T> run(QThreadPool *pool, Function &&f, Args &&...args)
As a side effect, if
f
is a pointer to a member function, the first argument of
args
should be the object for which that member is defined (or a reference, or a pointer to it). So instead of writing:
QImage image = ...; QFuture<void> future = QtConcurrent::run(&image, &QImage::invertPixels, QImage::InvertRgba);
You have to write:
QFuture<void> future = QtConcurrent::run(&QImage::invertPixels, &image, QImage::InvertRgba);
Another side effect is that
QtConcurrent::run()
will not work with overloaded functions anymore. For example, the code below won't compile:
void foo(int arg); void foo(int arg1, int arg2); ... QFuture<void> future = QtConcurrent::run(foo, 42);
The easiest workaround is to call the overloaded function through lambda:
QFuture<void> future = QtConcurrent::run([] { foo(42); });
Or you can tell the compiler which overload to choose by using a
static_cast
:
QFuture<void> future = QtConcurrent::run(static_cast<void(*)(int)>(foo), 42);
Or qOverload :
QFuture<void> future = QtConcurrent::run(qOverload<int>(foo), 42);
Other methods of QtConcurrent have no behavioral changes and do not introduce source compatibility breaks.
