Java JTree pickFirstIfNone(JTree tree)

Description

If an explicit pick has not been done then null will be returned.

License

LGPL

Parameter

Parameter	Description
tree	a parameter

Declaration

public static DefaultMutableTreeNode pickFirstIfNone(JTree tree) 

Method Source Code

//package com.java2s;
/*/* w w  w.j  a va2  s.c  om*/
Strandz LGPL - an API that matches the user to the data.
Copyright (C) 2007 Chris Murphy
    
Strandz LGPL is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
    
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.
    
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
    
    
The authors can be contacted via www.strandz.org
*/

import javax.swing.JTree;
import javax.swing.tree.DefaultMutableTreeNode;

import javax.swing.tree.TreePath;

public class Main {
    /**
     * If an explicit pick has not been done then null will be returned.
     *
     * @param tree
     * @return
     */
    public static DefaultMutableTreeNode pickFirstIfNone(JTree tree) {
        DefaultMutableTreeNode result = null;
        // Err.pr( "In pickFirstIfNone for " + tree);
        if (tree.isSelectionEmpty()) {
            // Err.pr( "pickFirstIfNone isSelectionEmpty true, SO NOW SELECTED FIRST");
            tree.setSelectionRow(0);
        }
        if (tree.getSelectionCount() != 1) {// Not an error - user may have selected another application and
                                            // then gone back to this one.
                                            // Err.error( "Expected one row to be selected");
        } else {
            TreePath treePath = tree.getSelectionPath();
            DefaultMutableTreeNode treeNode = (DefaultMutableTreeNode) treePath.getLastPathComponent();
            // Err.pr( "pickFirstIfNone to return " + treeNode);
            result = treeNode;
        }
        return result;
    }
}

Related

1. getTreeObject(JTree tree, Class type)
2. getTreeSelectionBorderColor()
3. isPointOnTree(JTree tree, Point location)
4. maxDepth(JTree tree, int depth)
5. paint(JTree tree)
6. printComponentTree(final JComponent fc)
7. RemoveAll(JTree tree)
8. repaintSelection(JTree tree)
9. restoreExpanstionState(JTree tree, int row, String expansionState)