Re: Setting the Focus on Java windows (JInternalFrames)

From:
"John B. Matthews" <nospam@nospam.invalid>
Newsgroups:
comp.lang.java.programmer
Date:
Sun, 28 Sep 2008 14:52:26 -0400
Message-ID:
<nospam-62E3AF.14522628092008@news.motzarella.org>
In article <gbnsmq$pmb$1@registered.motzarella.org>,
 RedGrittyBrick <RedGrittyBrick@spamweary.invalid> wrote:

RedGrittyBrick wrote:

Neo wrote:

I'm trying to set the focus on a Java JInternalFrame but it doesn't
work. Is this a bug? I have tried every method that contains the words
"focus": requestFoucs, setFocusable, etc. I want the window to have
the focus. Can someone show me how to do this?

[...]

I must remember not to post untested guesswork!

The OP needs setSelected(true).


RGB: I can't tell you how much fun I had with your fine example; sorry
if I mangled it while tinkering, below. [I commented out the @Override
annotations to suit my older compiler (1.5.0_16).]

<code>
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.util.ArrayList;
import java.beans.PropertyVetoException;
import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.JDesktopPane;
import javax.swing.JFrame;
import javax.swing.JInternalFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.SwingUtilities;

/**
  * How to switch "Focus" between JInternalFrames
  * @author RedGrittyBrick, John B. Matthews
  */
public class InternalFrameFocus {

    private static final int MAX = 5;
    private ArrayList<MyFrame> frames = new ArrayList<MyFrame>();

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            //@Override
            public void run() {
                new InternalFrameFocus().createAndShowGUI();
            }
        });
    }

    void createAndShowGUI() {

        JDesktopPane desktop = new JDesktopPane();
        desktop.setPreferredSize(new Dimension(300, 200));
        for (int i = 1; i <= MAX; i++) {
            MyFrame frame = new MyFrame(desktop, "F" + i, i * 20);
            frames.add(frame);
        }
        
        JMenu menu = new JMenu("Focus");
        for (int i = 0; i < MAX; i++) {
            menu.add(new JMenuItem(frames.get(i).getAction()));
        }
        JMenuBar bar = new JMenuBar();
        bar.add(menu);

        JFrame f = new JFrame("InternalFrameFocus");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.add(desktop);
        f.setJMenuBar(bar);
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }
}

class MyFrame extends JInternalFrame {

    private Action action;

    MyFrame(JDesktopPane desktop, String name, int offset) {
        this.setSize(120, 80);
        this.setLocation(offset, offset);
        this.setTitle(name);
        this.setVisible(true);
        desktop.add(this);
        action = new AbstractAction(name) {
            //@Override
            public void actionPerformed(ActionEvent ae) {
                try {
                    MyFrame.this.setSelected(true);
                } catch (PropertyVetoException e) {
                    e.printStackTrace();
                }
            }
        };
    }

    public Action getAction() { return action; }
}

</code>
--
John B. Matthews
trashgod at gmail dot com
home dot woh dot rr dot com slash jbmatthews

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