Solved

JTree Refresh

Posted on 2008-10-07
5
1,007 Views
Last Modified: 2012-05-07
I am using a JTree in my application that needs to be abel to have nodes added to it and removed from it dynamically. Using the following function, everything works, but after one node has been added, any subsequent nodes I add don't show up in the JTree. There are no Exceptions thrown and I can reference the node programmatically. Is there something special I need to do to update the display? Any help would be appreciated. Thank you.
public void addTransition( Transition transition ) 

    {

        DefaultMutableTreeNode node = new DefaultMutableTreeNode( transition ); 

        

        try 

        {

            transitionNode.add( node ); 

            treLayoutTree.scrollPathToVisible( new TreePath( node.getPath() ) );

        }

        catch ( Exception e ) 

        {

            Main.getLogger().writeToLogWarn( "MainWindow.addTransition() Exception: " + e.getMessage() ); 

        }

    }

Open in new window

0
Comment
Question by:Cmerf486
  • 2
  • 2
5 Comments
 
LVL 37

Expert Comment

by:zzynx
ID: 22666916
DefaultTreeModel has a method nodeStructureChanged() that might be useful in your case:

    /**
      * Invoke this method if you've totally changed the children of
      * node and its childrens children...  This will post a
      * treeStructureChanged event.
      */
    public void nodeStructureChanged(TreeNode node)

So, add the nodes you want.
Then perform the above method on the parent node
0
 
LVL 13

Accepted Solution

by:
MicheleMarcon earned 500 total points
ID: 22666952

Your add() does not send the event for tree model changed, so Jtree doesn't know that the model has changed.

(I personally have wasted a lot of time because of this!)

You must use

DefaultTreeModel.insertNodeInto()

;)
0
 
LVL 13

Expert Comment

by:MicheleMarcon
ID: 22666964
(I edited before zzynx comment was showed... so I wasn't referring to him/her)
0
 

Author Closing Comment

by:Cmerf486
ID: 31623597
Thanks a lot!
0
 

Author Comment

by:Cmerf486
ID: 22668686
zznyx,
Thanks for your entry and help!

MicheleMarcon,
Yours proved to be an easy solution, thanks. Here is my new code for anyone who might run into the same problem.
    public void addTransition( Transition transition ) 

    {

        DefaultMutableTreeNode node = new DefaultMutableTreeNode( transition ); 

        

        try 

        {

            ((DefaultTreeModel)(treLayoutTree.getModel())).insertNodeInto( node, transitionNode, transitionNode.getChildCount() );

        }

        catch ( Exception e ) 

        {

            Main.getLogger().writeToLogWarn( "MainWindow.addTransition() Exception: " + e.getMessage() ); 

        } 

    }

Open in new window

0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
base64 decode encode 12 122
bitbucket vs gitbucket 3 58
Java array passed to SQL where clause 23 64
why cannot we forward request once the response is committed 2 33
For beginner Java programmers or at least those new to the Eclipse IDE, the following tutorial will show some (four) ways in which you can import your Java projects to your Eclipse workbench. Introduction While learning Java can be done with…
By the end of 1980s, object oriented programming using languages like C++, Simula69 and ObjectPascal gained momentum. It looked like programmers finally found the perfect language. C++ successfully combined the object oriented principles of Simula w…
Viewers learn about the “while” loop and how to utilize it correctly in Java. Additionally, viewers begin exploring how to include conditional statements within a while loop and avoid an endless loop. Define While Loop: Basic Example: Explanatio…
This tutorial covers a practical example of lazy loading technique and early loading technique in a Singleton Design Pattern.

864 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

22 Experts available now in Live!

Get 1:1 Help Now