Problem with repainting, should be Threaded...

Question

Hello,
I want to smoothly animate a square to some coördinates of the screen, smoothly means with some time between new coörds.
I'm using the following code:
                    for(int i = 0; i<5; i++)
                         bx-=2;
                         repaint();
                         try
                              Thread.sleep(tijdTussenFrame);
                              System.out.println("Wacht nummer: "+i);
                         catch(Exception er)
                              System.out.println("error bij wachten voor pijl links!");
                    }However, I don't seem to repaint when the (small sleep times) are in use...
My paint Thread should be a different Thread than the one that is sleeping small times...
My full code:
* To change this template, choose Tools | Templates
* and open the template in the editor.
* @author Man Ik Weet
import java.applet.*;
import java.awt.event.*;
import java.awt.*;
//import java.net.URL; //alleen als er plaatjes worden geladen!
public class RPG extends Applet implements KeyListener, Runnable,MouseListener, MouseMotionListener
     //nodig voor extra Thread
     Thread painter = null;
     boolean threadSuspended;
     //Offscreen tekeken
     Graphics bg;
     Image offscreen;
     //dimensie scherm
     int width,height;
     //x en y muis
     int xm,ym = 0;
     //alles voor audio/plaatjes
     //URL base;
     //AudioClip geluidjeNaam;
     //Image plaatjeNaam;
     //MediaTracker mt; //alleen nodig als er plaatjes worden geladen van het internet
     //voor de FPS
     int fps = 25; //de frames per seconde, game sloom? zet dit hoger/lager;
     int tijdTussenFrame;
     //Voor het blokje dat reageert op de pijlen...
     int bx,by = 0;
     boolean keyInGedrukt = false; //als er een toets is gedruk wacht de thread, maar hij vangt wel andere toetsen dan op
     public void init()
          //zorg voor het laden van plaatjes en/of geluid
          /*try
               base = getDocumentBase();
          catch (Exception e)
          plaatjeNaam = getImage(base,"plaatjeNaam.png");
          mt.addImage(plaatjeNaam,1); 1 = hoeveelste plaatje
          naam = getAudioClip(base, "naam.au");
          try
              mt.waitForAll();
         catch (InterruptedException  e)
              System.out.println("Fout bij wachten voor alle plaatjes...");
          //zwarte achtergrond FTW
          setBackground(Color.black);
          //zet alles op voor muis/toetsenboord
          addKeyListener(this);
          addMouseListener(this);
          addMouseMotionListener(this);
          //pixels voor scherm, we willen niet te groot of te klein ;)
          width = getSize().width;
          height = getSize().height;
          offscreen = createImage(width, height);
          bg = offscreen.getGraphics();
          tijdTussenFrame = (1000/fps);
   public void start()
          if (painter == null )
               painter  = new Thread( this );
               painter.setPriority( Thread.MAX_PRIORITY );
               threadSuspended = false;
               painter.start();
          else
               if ( threadSuspended )
                    threadSuspended = false;
                    synchronized( this )
                         notify();
     public void stop()
          threadSuspended = true;
     public void run() {
          try
               while (true)
                    //hier doet het IETS? LMAO! muwahahahaha!
                    if (threadSuspended)
                         synchronized( this )
                              while (threadSuspended)
                                   wait();
                    repaint();
                    painter.sleep(tijdTussenFrame);  // interval given in milliseconds
          catch (InterruptedException e) { }
     public void paint(Graphics g)
          bg.clearRect(0,0,width,height);
          bg.setColor(Color.red);
          bg.drawString("Key ingedrukt: "+keyInGedrukt,width/2,height/2);
          bg.drawString(xm+";"+ym, xm, ym);
          bg.setColor(Color.cyan);
          bg.fillRect(bx, by, 10, 10);
          g.drawImage(offscreen,0,0,this);
     public void update(Graphics g)
          paint(g);
     public void mouseClicked(MouseEvent me)
          xm = me.getX();
          ym = me.getY();
     public void mousePressed(MouseEvent me)
     public void mouseReleased(MouseEvent me)
     public void mouseEntered(MouseEvent me)
     public void mouseExited(MouseEvent me)
     public void mouseDragged(MouseEvent me)
          xm = me.getX();
          ym = me.getY();
     public void mouseMoved(MouseEvent me)
          xm = me.getX();
          ym = me.getY();
    public void keyTyped(KeyEvent e)
        System.out.println("Key getypt.");
    public void keyPressed(KeyEvent e)
          if(keyInGedrukt==false)
               keyInGedrukt=true;
               System.out.println("Key ingedrukt.");
               if(e.getKeyCode()==KeyEvent.VK_LEFT)
                    System.out.println("Key pijl links.");
                    for(int i = 0; i<5; i++)
                         bx-=2;
                         repaint();
                         try
                              Thread.sleep(tijdTussenFrame);
                              System.out.println("Wacht nummer: "+i);
                         catch(Exception er)
                              System.out.println("error bij wachten voor pijl links!");
               if(e.getKeyCode()==KeyEvent.VK_RIGHT)
                    System.out.println("Key pijl rechts.");
                    bx+=10;
               if(e.getKeyCode()==KeyEvent.VK_UP)
                    System.out.println("Key pijl omhoog.");
                    by-=10;
               if(e.getKeyCode()==KeyEvent.VK_DOWN)
                    System.out.println("Key pijl naar beneden.");
                    by+=10;
          else
               System.out.println("Key is ingedrukt?");
    public void keyReleased(KeyEvent e)
          keyInGedrukt = false;
        System.out.println("Key losgelaten.");
        if(e.getKeyCode()==KeyEvent.VK_LEFT)
               System.out.println("Key pijl links losgelaten.");
               bx-=10;
          if(e.getKeyCode()==KeyEvent.VK_RIGHT)
               System.out.println("Key pijl rechts losgelaten.");
               bx+=10;
        if(e.getKeyCode()==KeyEvent.VK_UP)
               System.out.println("Key pijl omhoog losgelaten.");
               by-=10;
          if(e.getKeyCode()==KeyEvent.VK_DOWN)
               System.out.println("Key pijl naar beneden losgelaten.");
               by+=10;
}

Answer 1

Doesn't work that way. You have to remove the old Button and insert the new one:import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class ButtonExample extends JFrame implements ActionListener {
     JButton b1, b2;
     JLabel l1 = new JLabel("left");
     JLabel l2 = new JLabel("right");
     JPanel jp = new JPanel(new BorderLayout());
     ButtonExample() {
          setSize(800, 600);
          setDefaultCloseOperation(EXIT_ON_CLOSE);
          Container conPane = getContentPane();
          b1 = new JButton("First Click");
          b2 = new JButton("Second Click");
          b1.addActionListener(this);
          jp.add(l1,BorderLayout.EAST);
          jp.add(b1,BorderLayout.CENTER);
          jp.add(l2,BorderLayout.WEST);
          conPane.add(jp);
          pack();
          setVisible(true);
     public void actionPerformed(ActionEvent e) {
          if (e.getActionCommand() == "First Click") {
               System.out.println("fldf");
               jp.remove(b1);
               jp.add(b2,BorderLayout.CENTER);
               pack();
               validate();
     static public void main(String args[]) {
          ButtonExample fr = new ButtonExample();
}