Improve docs for Qt Concurrent run with promise mode

For the readers that are new to QtConcurrent, it may be confusing that unlike the normal usage of QPromise, they don't have to call start() or finish() when using Qt Concurrent run with promise mode. Be more explicit about that. Pick-to: 6.1 Change-Id: I08df6c4ca41bec4120e208a6643ee20c7adf265c Reviewed-by: Jarek Kobus <[email protected]> Reviewed-by: Leena Miettinen <[email protected]>
fwcd · Mar 4, 2021 · fcc453d · fcc453d
1 parent b627256
commit fcc453d
Showing 1 changed file with 9 additions and 0 deletions.
diff --git a/src/concurrent/qtconcurrentrun.cpp b/src/concurrent/qtconcurrentrun.cpp
@@ -194,6 +194,11 @@
 
     \snippet code/src_concurrent_qtconcurrentrun.cpp 11
 
+    \note There's no need to call QPromise::start() and QPromise::finish() to
+    indicate the beginning and the end of computation (like you would normally do when
+    using QPromise). QtConcurrent::run() will always call them before starting and
+    after finishing the execution.
+
     \section2 Suspending and canceling the execution
 
     The QPromise API also enables suspending and canceling the computation, if requested:
@@ -215,6 +220,10 @@
     call to \c promise.isCanceled() will return \c true and
     \c aFunction will return immediately without any further result reporting.
 
+    \note There's no need to call QPromise::finish() to stop the computation
+    after the cancellation (like you would normally do when using QPromise).
+    QtConcurrent::run() will always call it after finishing the execution.
+
     \section2 Progress reporting
 
     It's also possible to report the progress of a task