Program to create a simple mini paint application

In this program, we will create a simple mini paint application using Frame class. We have to implement two types of events here: Mouse event and Key event. To use this program you have to use numpad keys on keyboard. The following keys are used for specific purpose:





  1. Press '2' to move DOWN
  2. Press '8' to move UP  
  3. Press '4' to move LEFT
  4. Press '6' to move RIGHT
  5. Press '7' to move TOP LEFT
  6. Press '9' to move TOP RIGHT
  7. Press '1' to move BOTTOM LEFT
  8. Press '3' to move BOTTOM RIGHT

PROGRAM
import java.awt.*;
import java.awt.event.*;
import java.applet.*;

class MiniPaintApp extends Frame implements KeyListener
{
     String msg="";
     int x,y;
         
     MiniPaintApp()
     {
          setBounds(0,0,550,550);
          setTitle("Mini Paint Application");
          addKeyListener(this);
          addWindowListener(new WindowAdapter(){
           public void windowClosing(WindowEvent we)
           {
            System.exit(0);
           }
          });
          addMouseListener(new MouseAdapter(){
           public void mouseClicked(MouseEvent me)
           {
            x = me.getX();
            y = me.getY();
           }
          });
     }
     public void keyPressed(KeyEvent ke)
     {
      int keyCode = ke.getKeyCode();
        System.out.println("KeyTyped = "+ke.getKeyChar()+" keyCode = "+keyCode);
        System.out.println(KeyEvent.VK_NUMPAD8);
        switch( keyCode ) 
        { 
            case KeyEvent.VK_NUMPAD8: // move up
                 if(y > 51)
                  y-=1;
                 break;
            case KeyEvent.VK_NUMPAD2: // move down
              if(y < 419)
                  y+=1;
                 break;
            case KeyEvent.VK_NUMPAD4: // move left
                 if(x > 41)
                  x-=1;
                 break;
            case KeyEvent.VK_NUMPAD6 : // move right
                 if(x < 389)
                  x+=1;
                 break;
            case KeyEvent.VK_NUMPAD9 : // move upper right
                 if(x < 389 && y > 41)
                 {
                  x+=1;
                  y-=1;
                 }
                 break;
            case KeyEvent.VK_NUMPAD7 : // move upper left
                 if(x > 41 && y > 41)
                 {
                  x-=1;
                  y-=1;
                 }
                 break;
            case KeyEvent.VK_NUMPAD1 : // move lower left
                 if(x > 41 && y < 419)
                 {
                  x-=1;
                  y+=1;
                 }
                 break;
            case KeyEvent.VK_NUMPAD3 : // move lower right
                 if(x < 389 && y < 419)
                 {
                  x+=1;
                  y+=1;
                 }
                 break;
          }
          paint(getGraphics());
     }    
     public void keyTyped(KeyEvent ke) { }
     public void keyReleased(KeyEvent ke) { }
     
     public void paint(Graphics g)
     {
          g.fillRect(x,y,2,2);
          g.setFont(new Font("Cambria",Font.BOLD,17));
          g.drawString("First click to set starting point !!!",40,466);
          g.drawString("Press 8 to move UP",40,480);
          g.drawString("Press 2 to move DOWN",40,495);
          g.drawString("Press 4 to move LEFT",40,510);
          g.drawString("Press 6 to move RIGHT",40,525);
          g.drawString("Press 9 to move TOP RIGHT",240,480);
          g.drawString("Press 7 to move TOP LEFT",240,495);
          g.drawString("Press 1 to move BOTTOM LEFT",240,510);
          g.drawString("Press 3 to move BOTTOM RIGHT",240,525);
          g.setColor(Color.red);
          g.drawRect(40,50,400,400);
     }
     public static void main(String args[])
     {
          new MiniPaintApp().show();
     }
}
OUTPUT 
C:\>javac MiniPaintApp.java
C:\>java MiniPaintApp

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