Actionlistener/JComboBox clash

Question

I'm trying to write a program which will take the input from one drop-down box, and use that to calculate the drop down box for another field, but I keep running into a problem. To make it work, I have to remove all items from on JComboBox, before refilling it, but this causes the program to throw an exception.

jbox1.addActionListener(new ActionListener()
    {
    public void actionPerformed(ActionEvent e)
    {
    autoCalc();

    String s = jbox1.getSelectedItem().toString();
     workS.set1(s);  
    jbox2.removeAllItems();
     for(int i = 0; i <= workS.jbox1.getSelectedItem; i++)
         {
         String temp = ("" + i);
         jbox2.addItem(temp);
         } 
        autoCalc();
     }
});


jbox2.addActionListener(new ActionListener()
    {
    public void actionPerformed(ActionEvent e)
    {
    autoCalc();      
    String s = jbox2.getSelectedItem().toString();
     workS.set2(s);  
        autoCalc();
     }
});

As far as I can tell, removing all items from jbox2 calls the jbox2 actionlistener, which realises that the field is empty and throws an exception. Does anyone have a way around this?

In `jbox2`'s `actionPerformed` method, check to see if `s` is `null` or not. This occurs because when you remove all the elements from the combo box, the selected item is set to null, triggering the action event... — MadProgrammer, Sep 03 '12 at 00:12
As an alternative, consider the approach shown [here](http://stackoverflow.com/a/3191882/230513). — trashgod, Sep 03 '12 at 00:33
please show your actual code instead of snippets written on the fly (int i = 0; < getSelectedItem wouldn't compile), best as an SSCCE — kleopatra, Sep 03 '12 at 06:57

score 1 · Answer 1 · answered Sep 03 '12 at 05:58

1

Keep a reference of the ActionListener added to jbox2. Before removing the items and filling with new list remove the ActionListener and readd after model is filled with new items.

answered Sep 03 '12 at 05:58

StanislavL

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Actionlistener/JComboBox clash

1 Answers1