Why in Linux, JButton, JLabel mouse clicked is missing or ignored? its not doing how the program supposed to do

I have this SSCCE where Jbutton is getting pressed by it does not do anything, also if i click in JLabel it also fails, its not reliable, many click is getting missed. But some other distro i checked the same code, and it works. Only in Dell Inspiron Touch screen PC, its not working.

  • I have clicked JButton 100 times but it shows 2 times
  • I have clicked JLabel 100 times but it shows 0 times
  • I have also clicked in the JFrame 100 times but it shows 0 times was pressed

Run:

$ uname -a
Linux sun-Inspiron-One-2320 3.2.0-29-generic #46-Ubuntu SMP Fri Jul 27 17:03:23 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

$ lsb_release -a
No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 12.04.1 LTS
Release:	12.04
Codename:	precise

$ java -version
java version "1.6.0_24"
OpenJDK Runtime Environment (IcedTea6 1.11.5) (6b24-1.11.5-0ubuntu1~12.04.1)
OpenJDK 64-Bit Server VM (build 20.0-b12, mixed mode)

$ export DISPLAY=:0.0 && java -cp YumYumYum.jar UnitTest.MouseMethods
The JButton was clicked...
The JButton was clicked...


Copy & Paste:

package UnitTest;

import java.awt.FlowLayout;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;

public class MouseMethods implements MouseListener {

  private JLabel label = new JLabel("This is a JLabel");
  private JButton button = new JButton("This is a JButton");

  public MouseMethods() {
    JFrame frame = new JFrame("MouseMethods");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setLayout(new FlowLayout());

    label.addMouseListener(this);
    button.addMouseListener(this);

    frame.add(label);
    frame.add(button);
    frame.setVisible(true);
    frame.pack();
  }

  public void mouseClicked(MouseEvent e) {
    if (e.getSource().equals(button)) {
      System.out.println("The JButton was clicked...");
    } else if (e.getSource().equals(label)) {
      System.out.println("The JLabel was clicked...");
    } else {
      System.out.println("Something else was clicked...");
    }
  }

  public void mouseEntered(MouseEvent e) {
  }

  public void mouseExited(MouseEvent e) {
  }

  public void mousePressed(MouseEvent e) {
  }

  public void mouseReleased(MouseEvent e) {
  }

  public static void main(String args[]) {
    new MouseMethods();
  }
}


Follow up:

$ uname -a
Linux sun-Inspiron-One-2320 3.2.0-29-generic #46-Ubuntu SMP Fri Jul 27 17:03:23 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

$ apt-cache search linux-image
alsa-base - ALSA driver configuration files
linux-image - Generic Linux kernel image.
linux-image-3.2.0-23-generic - Linux kernel image for version 3.2.0 on 64 bit x86 SMP
linux-image-3.2.0-23-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-extra-3.2.0-23-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-extra-virtual - Linux kernel extra modules for virtual machines
linux-image-generic - Generic Linux kernel image
linux-image-server - Linux kernel image on Server Equipment.
linux-image-virtual - Linux kernel image for virtual machines
linux-virtual - Complete Linux kernel for virtual machines
linux-image-3.2.0-23-generic-pae - Linux kernel image for version 3.2.0 on 64 bit x86 SMP
linux-image-generic-pae - Generic Linux kernel image
linux-image-3.2.0-23-lowlatency - Linux kernel image for version 3.2.0 on x86/x86_64
linux-image-lowlatency - lowlatency Linux kernel image
linux-image-3.2.0-23-lowlatency-pae - Linux kernel image for version 3.2.0 on x86
linux-image-lowlatency-pae - lowlatency Linux kernel image
linux-image-3.2.0-24-generic - Linux kernel image for version 3.2.0 on 64 bit x86 SMP
linux-image-3.2.0-24-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-3.2.0-25-generic - Linux kernel image for version 3.2.0 on 64 bit x86 SMP
linux-image-3.2.0-25-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-3.2.0-26-generic - Linux kernel image for version 3.2.0 on 64 bit x86 SMP
linux-image-3.2.0-26-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-3.2.0-27-generic - Linux kernel image for version 3.2.0 on 64 bit x86 SMP
linux-image-3.2.0-27-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-3.2.0-29-generic - Linux kernel image for version 3.2.0 on 64 bit x86 SMP
linux-image-3.2.0-29-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-3.2.0-30-generic - Linux kernel image for version 3.2.0 on 64 bit x86 SMP
linux-image-3.2.0-30-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-3.2.0-31-generic - Linux kernel image for version 3.2.0 on 64 bit x86 SMP
linux-image-3.2.0-31-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-3.2.0-32-generic - Linux kernel image for version 3.2.0 on 64 bit x86 SMP
linux-image-3.2.0-32-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-3.2.0-33-generic - Linux kernel image for version 3.2.0 on 64 bit x86 SMP
linux-image-3.2.0-33-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-3.5.0-18-generic - Linux kernel image for version 3.5.0 on 64 bit x86 SMP
linux-image-current-generic - Depends on the most recently released generic kernel image and headers.
linux-image-extra-3.2.0-24-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-extra-3.2.0-25-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-extra-3.2.0-26-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-extra-3.2.0-27-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-extra-3.2.0-29-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-extra-3.2.0-30-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-extra-3.2.0-31-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-extra-3.2.0-32-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-extra-3.2.0-33-virtual - Linux kernel image for version 3.2.0 on 64 bit x86 Virtual Guests
linux-image-generic-lts-quantal - Generic Linux kernel image
linux-image-hwe-generic - Depends on the generic hardware enablement kernel image and headers.
linux-image-3.2.0-24-generic-pae - Linux kernel image for version 3.2.0 on 64 bit x86 SMP
linux-image-3.2.0-25-generic-pae - Linux kernel image for version 3.2.0 on 32 bit x86 SMP
linux-image-3.2.0-26-generic-pae - Linux kernel image for version 3.2.0 on 32 bit x86 SMP
linux-image-3.2.0-27-generic-pae - Linux kernel image for version 3.2.0 on 32 bit x86 SMP
linux-image-3.2.0-29-generic-pae - Linux kernel image for version 3.2.0 on 32 bit x86 SMP
linux-image-3.2.0-30-generic-pae - Linux kernel image for version 3.2.0 on 32 bit x86 SMP
linux-image-3.2.0-31-generic-pae - Linux kernel image for version 3.2.0 on 32 bit x86 SMP
linux-image-3.2.0-32-generic-pae - Linux kernel image for version 3.2.0 on 32 bit x86 SMP
linux-image-3.2.0-33-generic-pae - Linux kernel image for version 3.2.0 on 32 bit x86 SMP
linux-image-3.2.0-33-lowlatency - Linux kernel image for version 3.2.0 on x86/x86_64
linux-image-3.2.0-33-lowlatency-pae - Linux kernel image for version 3.2.0 on x86


$ apt-get install linux-image-3.2.0-33-generic
$ init 6
$ uname -a
Linux sun-Inspiron-One-2320 3.2.0-33-generic #52-Ubuntu SMP Thu Oct 18 16:29:15 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

Answers

Works as expected on Ubuntu 12.04/OpenJDK.

Notes:

  • Swing GUI objects should be constructed and manipulated only on the event dispatch thread.

  • Consider extends MouseAdapter over implements MouseListener.

  • Use ActionListener, such as Action, over MouseListener for buttons.

  • Listener on frame's content pane triggers final else clause.

Addendum: Note that overriding mouseClicked() may entail certain platform-dependent driver and control panel settings, such as double-click timing and mouse button de-bouncing. Override mousePressed() or mouseReleased() instead.

$ uname -a
Linux vm 3.2.0-33-generic-pae #52-Ubuntu SMP
    Thu Oct 18 16:39:21 UTC 2012 i686 i686 i386 GNU/Linux
$ lsb_release -a
No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 12.04.1 LTS
Release:	12.04
Codename:	precise
$ java -version
java version "1.6.0_24"
OpenJDK Runtime Environment (IcedTea6 1.11.5) (6b24-1.11.5-0ubuntu1~12.04.1)
OpenJDK Client VM (build 20.0-b12, mixed mode, sharing)

Code:

import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;

public class MouseMethods extends MouseAdapter {

    private JLabel label = new JLabel("This is a JLabel");
    private JButton button = new JButton("This is a JButton");

    public MouseMethods() {
        JFrame frame = new JFrame("MouseMethods");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLayout(new FlowLayout());

        label.addMouseListener(this);
        button.addMouseListener(this);
        frame.getContentPane().addMouseListener(this);

        frame.add(label);
        frame.add(button);
        frame.pack();
        frame.setVisible(true);
    }

    @Override
    public void mousePressed(MouseEvent e) {
        if (e.getSource().equals(button)) {
            System.out.println("The JButton was clicked...");
        } else if (e.getSource().equals(label)) {
            System.out.println("The JLabel was clicked...");
        } else {
            System.out.println("Something else was clicked...");
        }
    }

    public static void main(String args[]) {
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                new MouseMethods();
            }
        });
    }
}
Posted on by trashgod

I would suggest you not to implement listener in the class itself. I think that each component should have its own listener (branching by source is not probably the best idea)...

Also it's better to extend MouseAdapter if you don't need to implement all methods

Posted on by user219882