Android 碎屏效果 (Crack Screen,击碎屏幕)

本文介绍一个好玩的App   如图：

实现思路：在一个透明的Activity上用一个自定义View，然后在View上画.9的碎玻璃图片，加上音效。然后过一段时间消失。

主要用一个postInvalidate();方法，用一个集合去装手指触摸过的地方，在touch事件中调用postInvalidate();方法进行视图重新绘制。

需要注意的是，这里的播放音效和上篇博客 Android 闪电效果 (Electric Screen,电动屏幕) 中的播放音效一样，暂停音效的时候要传开始播放时得到的int返回值，和停止音效不一样。

可以通过限制集合长度来限制绘制的屏幕个数。

单独开启一个线程，过一段时间开始清除效果， 即直接操作集合，操作完了调用postInvalidate(); 重新绘图就可以了。

示例代码：

 

 

public class CustomView extends View {
private Paint mPaint;
private SoundPool mSoundPool;
private Map<Integer, Integer> mSoundMap = new HashMap<Integer, Integer>();
private int mIndex;
private Bitmap mBitmap;
private ArrayList<Float> mXPointList;
private ArrayList<Float> mYPointList;
private int mCount = 0;// 点击次数
private int mLength = 30;// 绘制总数
public CustomView(Context context, AttributeSet attrs) {
super(context);
mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setColor(Color.BLUE);
// mPaint.setAlpha(127);
mPaint.setStrokeWidth(2.0f);
this.setKeepScreenOn(true);
this.setFocusable(true);
this.setLongClickable(true);
this.mSoundPool = new SoundPool(5, AudioManager.STREAM_SYSTEM, 5);
this.mSoundMap.put(1, mSoundPool.load(context, R.raw.cfokwowbfv, 1));
this.mBitmap = BitmapFactory.decodeResource(getResources(),
R.drawable.screen);
mXPointList = new ArrayList<Float>();
mYPointList = new ArrayList<Float>();
new Thread(new Runnable() {
@Override
public void run() {
// TODO Auto-generated method stub
while (true) {
try {
Thread.sleep(4000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// mG++;
handler.sendEmptyMessage(0);
}
}
}).start();
}
@Override
public boolean onTouchEvent(MotionEvent arg1) {
// TODO Auto-generated method stub
switch (arg1.getAction()) {
case MotionEvent.ACTION_DOWN:
// drawBitmap(arg1.getX(), arg1.getY());
playSound();
mXPointList.add(arg1.getX());
mYPointList.add(arg1.getY());
postInvalidate();
mCount++;
if (mCount > mLength) {
mXPointList.remove(0);
mYPointList.remove(0);
mLength++;
}
break;
case MotionEvent.ACTION_UP:
break;
case MotionEvent.ACTION_MOVE:
break;
default:
break;
}
return super.onTouchEvent(arg1);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
for (int i = 0; i < mXPointList.size(); ++i) {
canvas.drawBitmap(mBitmap, mXPointList.get(i) - mBitmap.getWidth()
/ 2, mYPointList.get(i) - mBitmap.getHeight() / 2, null);
}
}
// 播放
public void playSound() {
mIndex = mSoundPool.play(mSoundMap.get(1), 1, 1, 0, 0, 1);
}
// 停止播放
public void stopSound() {
// Toast.makeText(getContext(), "zzzzz", 0).show();
mSoundPool.stop(mIndex);
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
// TODO Auto-generated method stub
Toast.makeText(getContext(), "keydown", Toast.LENGTH_SHORT).show();
return super.onKeyDown(keyCode, event);
}
// 更新界面
Handler handler = new Handler() {
public void handleMessage(Message msg) {
if (msg.what == 0) {
if (mCount != 0 && mXPointList.size() != 0) {
for (int i = 0; i < new Random()
.nextInt(mXPointList.size() + 1); i++) {
mXPointList.remove(0);
mYPointList.remove(0);
mLength++;
}
}
postInvalidate();
}
}
};
}

 

Github: https://github.com/OneHead/crack_screen2D

Weibo: http://weibo.com/2382477985