a moving object in a layeredPane

Posted on 2004-09-28
Medium Priority
Last Modified: 2011-10-03
Hi experts,

   I tried to put a moving object in a layeredPane which is in a Frame. It works fine if i add it to the code directly, but it doesn't work if i put it in a layeredPane first. Does anyone know what I did wrong ???

   please help ! many thanks.
//  MovingFigs.java

import java.lang.* ;
import javax.swing.*;
import javax.swing.event.* ;
import java.awt.* ;
import java.awt.event.* ;
import java.awt.image.BufferedImage;

public class MovingFigs extends JFrame implements ActionListener{
    private JLayeredPane layeredPane;
    private JPanel myPanel ;

    /** Creates a new instance of Main */
    public MovingFigs() {
        layeredPane = new JLayeredPane();
        layeredPane.setPreferredSize(new Dimension(300, 310));
         MovingCircle myCircle = new MovingCircle() ;
          layeredPane.add( myCircle, new Integer(0)) ;
            getContentPane().setLayout(null) ;
            getContentPane().add(layeredPane) ;
          setSize(800, 600);

    public void actionPerformed(ActionEvent e){}
     * @param args the command line arguments
    public static void main(String[] args) {
        // TODO code application logic here
         MovingFigs meow = new MovingFigs() ;
      //   meow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

// MovingCircle.java

import java.lang.* ;
import javax.swing.*;
import javax.swing.event.* ;
import java.awt.* ;
import java.awt.event.* ;
import java.awt.image.BufferedImage;

public class MovingCircle extends JPanel implements ActionListener{
    private int x = 30, y = 30 ;
    private final int DELTA_X = 10 ;
    /** Creates a new instance of Class */
    public MovingCircle() {
        javax.swing.Timer circleTimer = new Timer(250, this);
    public void actionPerformed(ActionEvent e){ repaint() ;}
    public void paintComponent(Graphics g) {
          Graphics2D g2d = (Graphics2D) g.create();
          g2d.clearRect(0, 0, getWidth(), getHeight());
          x += DELTA_X;
          g2d.fillOval(x, y, y, y);
          g2d.drawOval(x, y, y, y);
     } // paintComponent
} // MovingCircle

Question by:meow00
  • 2
LVL 92

Expert Comment

ID: 12175085
you aren't using any layout managers so you need to set the size and position of all components expicitly.

Author Comment

ID: 12176369
  Hi objects & experts,

     Now I set the size and position for all components, but it still doesn't work ..... did i miss anything ???  please help ! many many thanks !!!

          layeredPane.add( myCircle, new Integer(0)) ;
          layeredPane.setSize(20,20) ;
          layeredPane.setLocation(30,30) ;
            getContentPane().setSize(100,100) ;
            getContentPane().setLocation(50,50) ;
            getContentPane().add(layeredPane) ;
LVL 92

Accepted Solution

objects earned 1800 total points
ID: 12176407
have you set the size and position of myCircle?

Featured Post

The new generation of project management tools

With monday.com’s project management tool, you can see what everyone on your team is working in a single glance. Its intuitive dashboards are customizable, so you can create systems that work for you.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Java Flight Recorder and Java Mission Control together create a complete tool chain to continuously collect low level and detailed runtime information enabling after-the-fact incident analysis. Java Flight Recorder is a profiling and event collectio…
In this post we will learn how to connect and configure Android Device (Smartphone etc.) with Android Studio. After that we will run a simple Hello World Program.
Video by: Michael
Viewers learn about how to reduce the potential repetitiveness of coding in main by developing methods to perform specific tasks for their program. Additionally, objects are introduced for the purpose of learning how to call methods in Java. Define …
Viewers will learn how to properly install Eclipse with the necessary JDK, and will take a look at an introductory Java program. Download Eclipse installation zip file: Extract files from zip file: Download and install JDK 8: Open Eclipse and …
Suggested Courses

607 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question