Question

I create a JTree and model for it out in a class separate to the GUI class. The data for the JTree is extracted from a file.

Now in the GUI class the user can add files from the file system to an AWT list. After the user clicks on a file in the list I want the JTree to update. The variable name for the JTree is schemaTree.

I have the following code for the when an item in the list is selected:

private void schemaListItemStateChanged(java.awt.event.ItemEvent evt) {         int selection = schemaList.getSelectedIndex();         File selectedFile = schemas.get(selection);         long fileSize = selectedFile.length();         fileInfoLabel.setText('Size: ' + fileSize + ' bytes');          schemaParser = new XSDParser(selectedFile.getAbsolutePath());          TreeModel model = schemaParser.generateTreeModel();         schemaTree.setModel(model); } 

I’ve updated the code to correspond to the accepted answer. The JTree now updates correctly based on which file I select in the list.

Answer 1

I not sure that I’m understanding your question, but I’ll try…

The right thing to do should be, IMHO:

• get the file
• create a new TreeModel from your file
• give the model to the JTree

In pseudocode, it would look like that:

File newContent = getSelectedByUser(...); TreeModel newModel = new MyFileBasedTreeModel(newContent); //this next part must be done in the EventDispatcherThread myTree.setModel(newModel);  

then the JTree would be updated, without any call to repaint, etc.

Hope it helps