How to highlight Icon with mouse click ?

Question

This program will open up a JFileChooser, Select one or more than one images from your computer. It will display them as Icons.
I am trying to highlight any icon with mouseclick from the program below but I am not able to do it. Please help. Thanks in advance.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.image.BufferedImage;
import java.io.File;
import javax.swing.*;
import javax.swing.border.Border;
public class IconIllustrate extends JFrame implements ActionListener, MouseListener
JLabel[] lblimage = new JLabel[10];
JPanel panAttachment = new JPanel();
JPanel panButton = new JPanel();
JButton bAdd = new JButton("Add");
Component comp = null;
Component c = null;
boolean bolVal = false;
public IconIllustrate()
// TODO Auto-generated constructor stub
panButton.add(bAdd);
bAdd.addActionListener(this);
this.getContentPane().setLayout(new BorderLayout());
this.getContentPane().add(panAttachment, BorderLayout.CENTER);
this.getContentPane().add(panButton, BorderLayout.SOUTH);
* @param args
public static void main(String[] s)
// TODO Auto-generated method stub
IconIllustrate ii = new IconIllustrate();
ii.setLocation(300, 200);
ii.setTitle("Testing Highlight Icon");
ii.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ii.setSize(400, 300);
ii.setVisible(true);
public void actionPerformed(ActionEvent ae)
// TODO Auto-generated method stub
if(ae.getSource().equals(bAdd))
JFileChooser chooser = new JFileChooser();
chooser.setMultiSelectionEnabled(true);
int answer = chooser.showOpenDialog(this);
File[] file = null;
String[] fileName = new String[10];
if(answer == JFileChooser.OPEN_DIALOG)
file = chooser.getSelectedFiles();
ImageIcon icon;
try
for(int i = 0; i < file.length; i++)
icon = new ImageIcon(file.toString());
ImageIcon thumbnailIcon = new ImageIcon(getScaledImage(icon.getImage(), 50, 40));
lblimage = new JLabel[10];
lblimage[i] = new JLabel();
lblimage[i].addMouseListener(this);
lblimage[i].setName("" + i);
lblimage[i].setBorder(BorderFactory.createEmptyBorder());
lblimage[i].setVerticalTextPosition(JLabel.BOTTOM);
lblimage[i].setHorizontalTextPosition(JLabel.CENTER);
lblimage[i].setHorizontalAlignment(JLabel.CENTER);
lblimage[i].setIcon(thumbnailIcon);
panAttachment.add(lblimage[i]);
panAttachment.revalidate();
catch(Exception ex )
ex.printStackTrace();
private Image getScaledImage(Image srcImg, int w, int h)
BufferedImage resizedImg = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Graphics2D g2 = resizedImg.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
RenderingHints.VALUE_INTERPOLATION_BILINEAR);
g2.drawImage(srcImg, 0, 0, w, h, null);
g2.dispose();
return resizedImg;
public void mouseClicked(MouseEvent me)
// TODO Auto-generated method stub
int clickCount = me.getClickCount();
if(clickCount == 1 || clickCount == 2)
Component comp = me.getComponent();
Component c = comp.getComponentAt(me.getX(), me.getY());
// c.setPreferredSize(new Dimension(100, 100));
c.setBackground(Color.CYAN);
System.out.println("clickCount");
repaint();
this.panAttachment.revalidate();
public void mouseEntered(MouseEvent arg0)
// TODO Auto-generated method stub
public void mouseExited(MouseEvent arg0)
// TODO Auto-generated method stub
public void mousePressed(MouseEvent arg0)
// TODO Auto-generated method stub
public void mouseReleased(MouseEvent arg0)
// TODO Auto-generated method stub

Answer 1

Hi,
phungho2000 wrote:
Thank you for the Code. Now I am able to set the label border. I need to figure out how keep track of the last selected component so that I can reset the border.**g**
No, you have still fundamental misunderstood how listeners are working. You add a listener to a component. From this time on, this listener is watching this component. It listens if something occurs with this component therefor it is competent. If so, then it will pay attention to this. So the listener always knows the components it is in charge of. There is no need for you to "keep track of the last selected component" because the listener is doing this for you already.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.GridLayout;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import javax.swing.*;
public class FocusTesting extends JFrame implements FocusListener, MouseListener
  // There is no need for JLabel fields here.
  //JLabel labelA = new JLabel("Label A");
  //JLabel labelB = new JLabel("Label B");
  public FocusTesting()
    super("FocusTesting");
    JPanel paneFirst = new JPanel();
    JPanel paneSecond = new JPanel();
    paneSecond.setBackground(Color.gray);
    //use simply FlowLayout for testing this
    //paneFirst.setLayout(new BorderLayout());
    paneFirst.setBorder(BorderFactory.createBevelBorder(2));
    // pane.setBackground(Color.blue);
    JLabel labelA = new JLabel("Label A");
    // give the labelA a name only to show you, that the listener knows about the compontent it ist added to
    labelA.setName(labelA.getText());
    labelA.addMouseListener(this);
    labelA.addFocusListener(this);
    labelA.setFocusable(true);
    JLabel labelB = new JLabel("Label B");
    // give the labelB a name only to show you, that the listener knows about the compontent it ist added to
    labelB.setName(labelB.getText());
    labelB.addMouseListener(this);
    labelB.addFocusListener(this);
    labelB.setFocusable(true);
    paneFirst.add(labelA);
    paneFirst.add(labelB);
    this.getContentPane().setLayout(new GridLayout(2, 1));
    this.getContentPane().add(paneFirst);
    this.getContentPane().add(paneSecond);
  public static void main(String[] s)
    //separate the initial thread form the event dispatch thread
    SwingUtilities.invokeLater(new Runnable() {
      public void run() {
        FocusTesting ft = new FocusTesting();
        ft.setLocation(300, 200);
        ft.setSize(300, 200);
        ft.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        ft.setVisible(true);
  public void focusGained(FocusEvent fe)
    // TODO Auto-generated method stub
    JComponent jcomp = (JComponent)fe.getComponent();
    jcomp.setBorder(BorderFactory.createLineBorder(Color.GREEN, 5));
    System.out.println("focusGained " + jcomp.getName());
  public void focusLost(FocusEvent fe) 
    // TODO Auto-generated method stub
    JComponent jcomp = (JComponent)fe.getComponent();
    jcomp.setBorder(BorderFactory.createEmptyBorder());
    System.out.println("focusLost " + jcomp.getName());
  public void mouseClicked(MouseEvent me)
    Component comp = me.getComponent();
    comp.requestFocusInWindow();
    System.out.println("mouseClicked " + comp.getName());
  public void mouseEntered(MouseEvent arg0)
    // TODO Auto-generated method stub
  public void mouseExited(MouseEvent arg0)
    // TODO Auto-generated method stub
  public void mousePressed(MouseEvent arg0)
    // TODO Auto-generated method stub
  public void mouseReleased(MouseEvent arg0)
    // TODO Auto-generated method stub
} You also should read again the Java Tutorial about Concurrency in Swing. Especially why and how to separate the initial thread form the event dispatch thread. [http://java.sun.com/docs/books/tutorial/uiswing/concurrency/initial.html]
Also have a look on [http://java.sun.com/docs/books/tutorial/uiswing/misc/focus.html], especially [http://java.sun.com/docs/books/tutorial/uiswing/misc/focus.html#focusable] for why use the MouseListener too.
And if you have understood that all, then you may think about in what way it would be much easier to use JButton's instead of JLabel's for your clickable and focusable thumbnails.
best regards
Axel