java - Images do not appear in applet -

i working on game.i want add images applet not appear there until resize or minimize applet.i not know whether image observer wrong or not. images in right path.their in build , class folder correct spelling. wrong code? appreciated.

public class game extends japplet implements keylistener, runnable {  screendir sd; image ball; image flower;  public void init() {      sd = new screendir(this);     ball = getimage(getcodebase(), "ball.jpg");     ballb = new ball(50, 50, 30, 40, color.red, ball, sd);     sd.add(ball);     flower = getimage(getcodebase(), "flower.gif");      //class flower defined class ball     flowerf = new flower(60, 100, 30, 30, color.green, flower, sd);     sd.add(flower);  }  public void paint(graphics g) {     sd.draw(g);  }  //these moving ball  @override public void keytyped(keyevent e) { }  @override public void keypressed(keyevent e) { }  @override public void keyreleased(keyevent e) { }  @override public void run() {     while (true) {         repaint();         try {             thread.sleep(15);         } catch (interruptedexception ex) {}}}      public class screendir {  arraylist<object> olist; japplet parent;  public screendir(japplet parent) {     this.parent = parent;     olist = new arraylist<>(); }  public void add(object o) {     olist.add(o); }  image img; graphics og;  img  = parent.createimage(parent.getwidth(), parent.getheight()); og  = offimg.getgraphics();  for(int = 0;i<olist.size ();i++){          olist.get(i).draw(offg); }  g.drawimage (img,0, 0, parent);  }       public class ball extends object {  screendir sd;  public ball(int x, int y, int w, int h, color c, image pi, screendir sd) {     {         this.sd = sd;     } public void draw(graphics g) {     g.drawimage(pi, x, y, w, h, null); }   public abstract class object {      int x, y, w, h;     color c;     image pi;      public object(int x, int y, int w, int h, color c, image pi) {         this.x = x;         this.y = y;         this.w = w;         this.h = h;         this.c = c;         this.pi = pi;     }      public abstract void draw(graphics g) {     } 

applets load images asynchronously, images not loaded before applet goes paint. every java component worth mentioning implements imageobserver means updates on image loading. fix problem, change this:

g.drawimage(pi, x, y, w, h, null); 

to this:

g.drawimage(pi, x, y, w, h, this); 

update

i mistakenly thought drawimage method part of japplet (which imageobserver). might change method declaration & painting line to:

public void draw(graphics g, imageobserver io) {     g.drawimage(pi, x, y, w, h, io); } 

then call it, change:

sd.draw(g); 

to:

sd.draw(g, this);