How to pass results from EDT back to a different thread?

Question

I have the following use-case:

I have code executing in Thread A (not EDT). Then I want to ask the user a question, but this must be done on the EDT as it involves Swing code (opening a dialog etc). Finally, I want to pass the user's answer back to Thread A, so it can continue.

I'm struggling to find a good way to pass the user's answer back to Thread A. How do you do this?

Answer 1

FutureTask<Integer> dialogTask = new FutureTask<Integer>(new Callable<Integer>() {
  @Override public Integer call() {
    return JOptionPane.showConfirmDialog(...);
  }
});
SwingUtilities.invokeLater(dialogTask);
int result = dialogTask.get();