Android截屏SurfaceView黑屏问题的解决办法

public class SuperSurfaceView extends SurfaceView implements SurfaceHolder.Callback {
 SurfaceHolder surfaceHolder;
 
 public SuperSurfaceView(Context context) {
  super(context);
  surfaceHolder = this.getHolder();
  surfaceHolder.addCallback(this);
 }
 
 @Override
 public void surfaceChanged(SurfaceHolder holder, int format, int width,
        int height) {
 
 }
 
 @Override
 public void surfaceCreated(SurfaceHolder holder) {
  new Thread(new MyThread()).start();
 }
 
 @Override
 public void surfaceDestroyed(SurfaceHolder holder) {
 
 }
 
 class MyThread implements Runnable {
  @Override
  public void run() {
   Canvas canvas = surfaceHolder.lockCanvas(null);//获取画布
   Paint mPaint = new Paint();
   mPaint.setColor(Color.BLUE);
   canvas.drawRect(new RectF(100, 100, 1000, 550), mPaint);
   surfaceHolder.unlockCanvasAndPost(canvas);//解锁画布，提交画好的图像
 
  }
 }
}

public abstract class SuperSurfaceView extends SurfaceView implements SurfaceHolder.Callback {
 SurfaceHolder surfaceHolder;
 
 public SuperSurfaceView(Context context) {
  super(context);
  surfaceHolder = this.getHolder();
  surfaceHolder.addCallback(this);
 }
 
 @Override
 public void surfaceChanged(SurfaceHolder holder, int format, int width,
        int height) {
 
 }
 
 @Override
 public void surfaceCreated(SurfaceHolder holder) {
  new Thread(new MyThread()).start();
 }
 
 @Override
 public void surfaceDestroyed(SurfaceHolder holder) {
 
 }
 
 class MyThread implements Runnable {
  @Override
  public void run() {
   Canvas canvas = surfaceHolder.lockCanvas(null);//获取画布
   doDraw(canvas);
   surfaceHolder.unlockCanvasAndPost(canvas);//解锁画布，提交画好的图像
 
  }
 }
 
 //将绘制图案的方法抽象出来，让子类实现，调用getBitmap方法时就会调用此方法
 protected abstract void doDraw(Canvas canvas);
 
 //调用该方法将doDraw绘制的图案绘制在自己的canvas上
 public Bitmap getBitmap() {
  Bitmap bitmap = Bitmap.createBitmap(getWidth(), getHeight(), Bitmap.Config.ARGB_8888);
  Canvas canvas = new Canvas(bitmap);
  doDraw(canvas);
  return bitmap;
 }
}

Button bt = (Button) findViewById(R.id.bt);
FrameLayout fl = (FrameLayout) findViewById(R.id.fl);
//用到surfaceview需继承SuperSurfaceView才能截到屏，否则截出来是黑屏
SuperSurfaceView surfaceView = new SuperSurfaceView(this) {
 @Override
 protected void doDraw(Canvas canvas) {
  Paint mPaint = new Paint();
  mPaint.setColor(Color.BLUE);
  canvas.drawRect(new RectF(100, 100, 1000, 550), mPaint);
 }
};
fl.addView(surfaceView);
 
bt.setOnClickListener(new View.OnClickListener() {
 @Override
 public void onClick(View v) {
  //调用该方法即可得到surfaceview上绘制的图案
  Bitmap bitmap = surfaceView.getBitmap();
 }
});