JList ListSelectionListener executes twice! I only need it to run one time.

Question

Hi everyone!
I am having trouble with my list selection listener. Every time I select an item in the JList the code for my listener runs twice.
For example, the code snipet like this:
ListSelectionListener listSelectionListener1 = new ListSelectionListener(){
          public void valueChanged(ListSelectionEvent listSelectionEvent){
               System.out.println("Hello");
     };This will print "Hello" twice and I can't figure out why. It is murdering my program. I have another way of getting around it but it is not very efficient and it makes the program much slower due to a special engine I have initiated during runtime. If there is a way to only get the code to execute once I would appreciate any help.
Thanks!
~Chris

Answer 1

See ListSelectionEvent#getValueIsAdjusting
One event is fired every time the list selection changes, for instance, if the user is selecting 5 files by dragging, 5 events will be fired with getValueIsAdjusting == true. Finally, another ListSelectionEvent is fired with getValueIsAdjusting == false, indicating that the selection process is finished. Seems you only want this last event, so just check the event object so see whether or not to react to it.