Java Swing多个ActionListener

Question

I am trying to keep actions separate as possible but am coming across the problem of an action firing off before the other. Right now I have a button that has two action listeners added.

JButton button = new JButton ();
...
button.addActionListener (new Action1 ());
button.addActionListener (new Action2 ());

2 is happening before 1. How can I guarantee the order? Is there a way to have an action that triggers other actions?

Answer 1

Usually, event sources make no guarantees about the order in which listeners are notified. And that is for a reason: the pattern/concept is about decoupling the listener code, ie listeners should be independent of each other.

If Action1 and Action2 really need to coordinate their work, the code should not be spread in two places.

Answer 2

If the two actions are dependent in their order, then it is functionally one action. I would only register the first actionlistener and call the second one directly from within the first one or - even better - write the code in one single actionlistener.