How to edit a JTree node with a single-click

Question

I have a JTree, and would like for its getTreeCellEditorComponent() method to be invoked when I single click on a node. According to the documentation for the DefaultTreeCellEditor class (which I extended), "Editing is started on a triple mouse click, or after a click, pause, click and a delay of 1200 miliseconds." Is there some way to override this behavior, so that a single-click could start the editing process?

hmm ... you might re-consider the usability of a single click: that's the trigger to un/selection — kleopatra, Mar 26 '13 at 13:08

score 6 · Answer 1 · edited May 23 '17 at 12:23

6

The JTree API recommends a MouseListener, but a key binding is also handy. This example invokes startEditingAtPath() and binds to the Enter key:

final JTree tree = new JTree();
tree.setEditable(true);
MouseListener ml = new MouseAdapter() {
    @Override
    public void mousePressed(MouseEvent e) {
        int row = tree.getRowForLocation(e.getX(), e.getY());
        TreePath path = tree.getPathForLocation(e.getX(), e.getY());
        if (row != -1) {
            if (e.getClickCount() == 1) {
                tree.startEditingAtPath(path);
            }
        }
    }
};
tree.addMouseListener(ml);
tree.getInputMap().put(
    KeyStroke.getKeyStroke(KeyEvent.VK_ENTER, 0), "startEditing");

Addendum: See also this answer regarding usability.

edited May 23 '17 at 12:23

Community

1
1

answered Mar 26 '13 at 11:49

trashgod

203,806
29
246
1,045

Only possible by learning from [top contributors like you!](http://stackoverflow.com/tags/swing/topusers). – trashgod Mar 26 '13 at 12:27
2

>100k (congrats, of course :-) or not: this is not an answer to the question and jtree already _has_ a binding (to F2 if I remember correctly) – kleopatra Mar 26 '13 at 12:40
@kleopatra: Right about `F2` on most platforms, but not `AquaLookAndFeel`. – trashgod Mar 26 '13 at 17:30
... so it has no binding to start edit at all? Interesting, item to insert into local knowledgebase :-) – kleopatra Mar 27 '13 at 08:26
@kleopatra: Yes. As far as I can tell, `JTree` for `AquaLookAndFeel` has only the two mouse click gestures mentioned in the question. Would invoking `startEditingAtPath()` in a `MouseListener` be an alternative? – trashgod Mar 27 '13 at 11:08
curious: why looking for an alternative - doesn's my answer work on mac? – kleopatra Mar 27 '13 at 11:16
@kleopatra: Perfectly; just looking to improve this answer. – trashgod Mar 27 '13 at 11:22
2

adding a kludge couldn't really improve it :-) see @mKorbel's comment on my answer: the referenced link does the startEditingPath (though in a selectionListener), it is possible but by-passes api designed to get it working - which is not the best of ideas, IMO – kleopatra Mar 27 '13 at 11:25

score 4 · Answer 2 · answered Mar 26 '13 at 13:11

4

Technically, you can subclass DefaultTreeCellEditor and tweaks its logic to start editing on the first single click:

JTree tree = new JTree();
tree.setEditable(true);
TreeCellEditor editor = 
        new DefaultTreeCellEditor(tree, (DefaultTreeCellRenderer) tree.getCellRenderer()) {
    @Override
    protected boolean canEditImmediately(EventObject event) {
        if((event instanceof MouseEvent) &&
           SwingUtilities.isLeftMouseButton((MouseEvent)event)) {
            MouseEvent       me = (MouseEvent)event;

            return ((me.getClickCount() >= 1) &&
                    inHitRegion(me.getX(), me.getY()));
        }
        return (event == null);
    }
};
tree.setCellEditor(editor);

There's a usability quirk, though, as now you can't select without starting an edit - which may or may not be your intention.

answered Mar 26 '13 at 13:11

kleopatra

51,061
28
99
211

maybe not [see post by @Michael Dunn](http://www.coderanch.com/t/584508/GUI/java/change-DefaultCellEditor-setClickCountToStart-int-DefaultTreeCellEditor) – mKorbel Mar 26 '13 at 13:18
1

@mKorbel I'm a bit weary of by-passing the editor api and manually starting the edit. Anyway, the row _is selected_ only it feels a bit unusual to not being able to select without editing .. – kleopatra Mar 26 '13 at 13:27
question is like it is, I'm doubt that your good sugestion, with clear concept will be accepted ... – mKorbel Mar 26 '13 at 13:47

How to edit a JTree node with a single-click

2 Answers2

Linked