The easiest way, of which I can think, is to make a switcher - boolean variable, that will be checked every time in your listener before it starts to really do something. Then you can start all of you modifications with switching this variable off. In case of multithreading, you may need some synchronization here.
Nevermind.. Finally realized I should've been using addMouseListener() on JList instead of ListSelectionListener. The MouseListener just needs to check to make sure that the user has clicked a valid selection/index in the JList before performing action. It's working now.
– Jyncus Mar 19 at 5:47 i'm having the same problem but the MouseListener seems not to react, can I see your implementation of this method? – JBoy Jun 21 at 13:23.
I'm fairly new to Java, and have exhausted my Google'ing for this problem with selection on a JList component. I have a list of strings that dynamically change when the user clicks various JButtons. My JList selection mode is set to SINGLE_SELECTION, and the ListSelectionModel is registered to a custom ListSelectionChangeHandler that implements ListSelectionListener.
My problem is that every time the JList model's contents get modified (by clicking a JButton), the ListSelectionChangeHandler gets called and a NullPointerException occurs - e.g. The user has an item selected in the list, clicks a button, the list contents change, and the listener gets called. I want the ListSelectionListener to only perform some action when a MouseClick fires the event. How can I prevent my listener from firing when the model data gets modified?
Thanks for the help!
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.