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How to manipulate data from a JList component

Posted on 2004-08-10
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Last Modified: 2012-05-05
Hi all,

I have a UI with two multi selection JList components, side by side.  When the user presses a button, I want the currently selected list items to be removed from one list, and placed in the other list.

It seems I am missing something however, since I can only see functions to populate the whole list, not add or remove items.  Here's my code so far:

  public void actionPerformed(ActionEvent event) {
    Object source = event.getSource();
    if(source == addButton) {
      Object[] selectedItems = (Object[])list1.getSelectedValues();
      list2.setListData(selectedItems);  // need to replace this
    }
  }

I want to replace the last line with functionality to remove the selectedItems from list1 and place them in list2.  Can anyone help?
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Question by:Dawkins
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6 Comments
 
LVL 35

Accepted Solution

by:
TimYates earned 50 total points
ID: 11763771
You need to use a DefaultListModel;

  DefaultListModel leftModel = new DefaultListModel() ;
  DefaultListModel rightModel = new DefaultListModel() ;

Then set the models into the lists:

   leftList.setModel( leftModel ) ;
   rightList.setModel( rightModel ) ;

then move the elements between the models, and the lists will update :-)

Tim
0
 
LVL 5

Expert Comment

by:TrekkyLeaper
ID: 11763777
The best way to do this is to use a ListModel (http://java.sun.com/j2se/1.4.2/docs/api/javax/swing/ListModel.html). If you implement a ListModel, you can use it as the underlying implementation of the list. Or you can use a DefaultListModel (http://java.sun.com/j2se/1.4.2/docs/api/javax/swing/DefaultListModel.html). That one will probably give you as much functionality as you need. You can pass the model in through the JList constructor.
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LVL 5

Expert Comment

by:TrekkyLeaper
ID: 11763784
Tim, you type to fast. =)
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LVL 35

Expert Comment

by:TimYates
ID: 11763811
>  Tim, you type to fast. =)

Hehehe :-D
0
 

Author Comment

by:Dawkins
ID: 11764389
Ah I thought I needed to use ListModels but couldn't quite get how!  Thanks :)

>  Tim, you type to fast. =)

he has to to have a chance of beating Objects and CEHJ  ;)
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