Android游戏开发之爆炸效果

在做Android游戏MagicBubble开发的时候，在连通两个Bubbles的时候，Bubble会以水泡爆破的情形消失。为了实现这一效果，我查找了不少资料，希望能找到一些标准的实现方面，花了不少时间，发觉Android关于游戏开发的资料实在太少了，更不用说标准做法了，没办法，只能按照自己的思路来实现这一效果。

我的思路是这样的（仅供参考，希望有更好做法的朋友跟我们共享一下）：在FrameLayout里面加入一ImageView，再定义一个爆炸的Animation，不需要的时候，ImageView就隐藏起来，需要的时候，就把ImageView移动到需要的地方，再StartAnimation，这样，就可以实现爆炸的效果。

下面是简化后的程序的代码，程序的效果如下：点中屏幕中任意地方，就在点击地方显示爆炸效果。

首先是Animation的定义，定义一个Frame Animation，依次播放5帧动画，每帧动画持续时间为50毫秒:

<animation-listxmlns:android="http://schemas.android.com/apk/res/android"
 android:oneshot="true">
 <itemandroid:drawable="@drawable/explode1"android:duration="50"/>
 <itemandroid:drawable="@drawable/explode2"android:duration="50"/>
 <itemandroid:drawable="@drawable/explode3"android:duration="50"/>
 <itemandroid:drawable="@drawable/explode4"android:duration="50"/>
 <itemandroid:drawable="@drawable/explode5"android:duration="50"/>
 </animation-list>

<animation-list xmlns:android="http://schemas.android.com/apk/res/android"
    android:oneshot="true">
    <item android:drawable="@drawable/explode1" android:duration="50" />
    <item android:drawable="@drawable/explode2" android:duration="50" />
    <item android:drawable="@drawable/explode3" android:duration="50" />
    <item android:drawable="@drawable/explode4" android:duration="50" />
    <item android:drawable="@drawable/explode5" android:duration="50" />  
</animation-list>

接着是主程序代码：

packagecom.ray.bubble;

 importandroid.app.Activity;
 importandroid.content.Context;
 importandroid.graphics.drawable.AnimationDrawable;
 importandroid.os.Bundle;
 importandroid.view.MotionEvent;
 importandroid.view.View;
 importandroid.view.Window;
 importandroid.view.WindowManager;
 importandroid.view.View.OnTouchListener;
 importandroid.widget.FrameLayout;
 importandroid.widget.ImageView;

 publicclassBubbleExplosionextendsActivity{
 privateFrameLayoutfl;
 privateExplosionViewexv1;
 privateAnimationDrawableexa1;
 publicvoidonCreate(BundlesavedInstanceState){
 super.onCreate(savedInstanceState);
 //setfullscreen
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
 fl=newFrameLayout(this);
fl.setBackgroundResource(R.drawable.bg);

 exv1=newExplosionView(this);
exv1.setVisibility(View.INVISIBLE);
exv1.setBackgroundResource(R.anim.explosion);
exa1=(AnimationDrawable)exv1.getBackground();
fl.addView(exv1);
 fl.setOnTouchListener(newLayoutListener());
setContentView(fl);
}

 classExplosionViewextendsImageView{

 publicExplosionView(Contextcontext){
 super(context);
}
 //handlethelocationoftheexplosion
 publicvoidsetLocation(inttop,intleft){
 this.setFrame(left,top,left+40,top+40);
}
}

 classLayoutListenerimplementsOnTouchListener{

 publicbooleanonTouch(Viewv,MotionEventevent){
 //firstly，uhavetostoptheanimation,iftheanimation
 //isstarting,ucannotstartitagain!
exv1.setVisibility(View.INVISIBLE);
exa1.stop();
 floatx=event.getX();
 floaty=event.getY();
 exv1.setLocation((int)y-20,(int)x-20);
exv1.setVisibility(View.VISIBLE);
exa1.start();
 returnfalse;
}

}
}

package com.ray.bubble;

import android.app.Activity;
import android.content.Context;
import android.graphics.drawable.AnimationDrawable;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.view.View.OnTouchListener;
import android.widget.FrameLayout;
import android.widget.ImageView;

public class BubbleExplosion extends Activity {
	private FrameLayout fl;
	private ExplosionView exv1;
	private AnimationDrawable exa1;
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //set full screen
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams. FLAG_FULLSCREEN ,
                      WindowManager.LayoutParams. FLAG_FULLSCREEN);
        fl = new FrameLayout(this);
        fl.setBackgroundResource(R.drawable.bg);
        
        exv1 = new ExplosionView(this);
		exv1.setVisibility(View.INVISIBLE);
	    exv1.setBackgroundResource(R.anim.explosion);
	    exa1 = (AnimationDrawable)exv1.getBackground();
		fl.addView(exv1);
		fl.setOnTouchListener(new LayoutListener());
        setContentView(fl);
    }
    
    class ExplosionView extends ImageView{

		public ExplosionView(Context context) {
			super(context);
		}
		//handle the location of the explosion
		public void setLocation(int top,int left){
			this.setFrame(left, top, left+40, top+40);
		}	
    }
    
    class LayoutListener implements OnTouchListener{

		public boolean onTouch(View v, MotionEvent event) {
			//firstly， u have to stop the animation,if the animation
			//is starting ,u can not start it again!
			exv1.setVisibility(View.INVISIBLE);
			exa1.stop();
			float x = event.getX();
			float y = event.getY();
			exv1.setLocation((int)y-20, (int)x-20);
			exv1.setVisibility(View.VISIBLE);
			exa1.start();
			return false;
		}
    	
    }
}

配合Android的SurfaceView，Animation可以实现很好的过渡效果，SurfaceView的用法很简单，可参考：

http://rayleung.javaeye.com/blog/420410

• BubbleExplosion.rar (163.5 KB)