JTree komplett aufklappen

Java-Forum AWT, Swing, JavaFX & SWT
1

Eine Sache die mich schon einige Zeit stört/interessiert, wie kann ich am Einfachsten einen kompletten JTree aufklappen?

2 


// If expand is true, expands all nodes in the tree.
// Otherwise, collapses all nodes in the tree.
public void expandAll(JTree tree, boolean expand) {
    TreeNode root = (TreeNode) tree.getModel().getRoot();
    // Traverse tree from root
    expandAll(tree, new TreePath(root), expand);
}

private void expandAll(JTree tree, TreePath parent, boolean expand) {
    // Traverse children
    TreeNode node = (TreeNode) parent.getLastPathComponent();
    if (node.getChildCount() >= 0) {
        for (Enumeration e = node.children(); e.hasMoreElements();) {
            TreeNode n = (TreeNode) e.nextElement();
            TreePath path = parent.pathByAddingChild(n);
            expandAll(tree, path, expand);
        }
    }
    // Expansion or collapse must be done bottom-up
    if (expand) {
        tree.expandPath(parent);
    } else {
        tree.collapsePath(parent);
    }
}```
3

Ich habs beführchtet, so einfach geht das also nicht :smiley:
Danke :slight_smile:

4

Ich mach das in meinem JXTree so ähnlich. cancelEditing ist ne super Idee vorher.

 * Expands all paths in the tree.
 * 
 * @see JTree#expandPath(TreePath)
 */
public void expandAll() {
  cancelEditing();
  final TreeModel tm = getModel();
  final Object root = tm.getRoot();

  /* nothing to expand, if no root */
  if (root != null) {
    expandAllPaths(new TreePath(root), tm);
  }
}

/**
 * Opens all paths in the given node and all nodes below that.
 * 
 * @param path the tree path to the node to expand
 * @see JTree#expandPath(TreePath)
 */
public void expandAllPaths(TreePath path) {
  cancelEditing();
  expandAllPaths(path, getModel());
}

/**
 * Opens all paths in the given node and all nodes below that.
 * 
 * @param path the tree path to the node to expand
 * @param treeModel the tree model
 * @see JTree#expandPath(TreePath)
 */
protected void expandAllPaths(TreePath path, TreeModel treeModel) {
  expandPath(path);
  final Object node = path.getLastPathComponent();
  final int n = treeModel.getChildCount(node);
  for (int index = 0; index < n; index++) {
    final Object child = treeModel.getChild(node, index);
    if (treeModel.getChildCount(child) > 0) {
      expandAllPaths(path.pathByAddingChild(child));
    }
  }
}

Ebenius