Is there a way to detect when a QT QRunnable object is done?

Question

Is there a way to detect when a QT QRunnable object is done? (Other than manually creating some signalling event at the end of the run() method.)

Answer 1

You can simply use QtConcurrent to run the runnable and use a QFuture to wait for finished.

#include <QtConcurrentRun>

class MyRunnable : public Runnable{
  void run();
}

in order to run and wait for it you can do the following

//create a new MyRunnable to use
MyRunnable instance;

//run the instance asynchronously
QFuture<void> future = QtConcurrent::run(&instance, &MyRunnable::run);

//wait for the instance completion
future.waitForFinished();

Qtconcurrent::run will start a new thread to execute method run() on instance and immediately returns a QFuture that tracks instance progress.

Notice however that using this solution you are responsable to keep instance in memory during the execution.