import java.awt.*;
import java.net.URL;
import java.net.MalformedURLException;
import java.lang.InterruptedException;
import java.applet.Applet;
import java.applet.AudioClip;
//定義BoomButton類
public class BoomButton extends java.applet.Applet implements Runnable {
  private Image img[] = new Image[6];//定義一個存放圖像的數組
  public int state = 0;//定義一個表示程序狀態的標志
  private AudioClip clip1;//定義聲音文件
  Thread anim;//定義anim線程
  Button goButton=null;//定義一個按鈕對象
  String button_text;//定義一個存放按鈕名稱的String對象
  //初始化程序
  public void init(){
    MediaTracker tracker = new MediaTracker(this);//定義MediaTracker類
    button_text = getParameter("button_text");//獲得按鈕名稱參數
    goButton = new Button(button_text);//實例化按鈕
    add(goButton);//將按鈕組件添加到Applet中

    clip1 = getAudioClip(getCodeBase(), "sounds/Explosion-3.au");//加載聲音文件
    img[0] = getImage(getDocumentBase(), "images/home2.gif");//加載圖像
    tracker.addImage(img[0], 0);//將圖像添加到MediaTracker中
    img[1] = getImage(getDocumentBase(), "images/bang1.gif");
    tracker.addImage(img[1], 0);
    img[2] = getImage(getDocumentBase(), "images/puff1.gif");
    tracker.addImage(img[2], 0);
    img[3] = getImage(getDocumentBase(), "images/puff2.gif");
    tracker.addImage(img[3], 0);
    img[4] = getImage(getDocumentBase(), "images/puff3.gif");
    tracker.addImage(img[4], 0);
    img[5] = getImage(getDocumentBase(), "images/puff4.gif");
    tracker.addImage(img[5], 0);
    //設置線程參數
    Thread.currentThread().setPriority(Thread.MIN_PRIORITY);
    try { tracker.waitForAll(); }//等待，以便使所有的圖片都被加載
    catch (InterruptedException e) {//如果被打擾，拋出異常
      System.out.println("當程序在加載圖像時被打擾！");
      System.exit(0);
    }
    Thread.currentThread().setPriority(Thread.NORM_PRIORITY);
  }
  //啟動線程
  public void start(){
    anim=null;
    repaint();
  }
  //停止線程
  public void stop(){
    if (anim!=null) {
      anim.stop();
      anim=null;
    }
  }
  public void destroy(){
  }
 //action方法
  public boolean action(Event evt, Object obj) {
    if (obj.equals(button_text)) {
      anim = new Thread(this);
      anim.start();
      removeAll();
      return(true);
    }
    return false;
  }
  //處理mouseDown事件
  public boolean mouseDown(Event f, int x, int y){
     add(goButton);
    return(true);
  }
  //處理mouseUp事件
  public boolean mouseUp(Event e, int x, int y){
        return(true);
  }
  //處理mouseEnter事件
  public boolean mouseMove(Event e, int x, int y){
        showStatus("");
        return(true);
  }
  //處理mouseEnter事件
  public boolean mouseEnter(Event e, int x, int y){
        showStatus("");
        return(true);
  }
  //處理mouseExit事件
  public boolean mouseExit(Event e, int x, int y){
        return(true);
  }
 //paint方法
  public void paint(Graphics g){
    switch (state)// switch多分支選擇語句
      {
      case 0:
        break;
      case 1:                   // 爆炸1 (閃爍)
        g.drawImage(img[1], 0, 0, this);
        break;
      case 2:                   // 爆炸2 (冒煙)
        g.drawImage(img[2], 0, 0, this);
        break;
      case 3:                   // 爆炸3
        g.drawImage(img[3], 0, 0, this);
        break;
      case 4:                   // 爆炸4
        g.drawImage(img[4], 0, 0, this);
        break;
      case 5:                   // 爆炸5
        g.drawImage(img[5], 0, 0, this);
        break;
      } 
  } 
  //運行線程
  public void run() {
    //播放聲音文件 
    if (clip1 != null) clip1.play();
        for (state=1; state<=5; state++) {
          repaint();
          try {anim.sleep(75);}
          catch (InterruptedException e){}
        }
	state=0;
	repaint();
  }
}