android - 合并两个位图并在android中另存为jpg格式？

Question

我的项目中有两个位图，我需要将这两个位图组合起来，并将这些位图组合成一个图像，我将展示我的代码

public class FotosurpriseActivity extends Activity {
/** Called when the activity is first created. */
Bitmap overlay;      
Paint pTouch;
int X = -100;
int Y = -100;
Canvas c2;
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    Bitmap mBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.android);
    Bitmap mBitmapover = BitmapFactory.decodeResource(getResources(), R.drawable.ss);
    overlay = BitmapFactory.decodeResource(getResources(),R.drawable.ss).copy(Config.ARGB_8888, true);  
    c2 = new Canvas(overlay);

    pTouch = new Paint(Paint.ANTI_ALIAS_FLAG);         
  //  pTouch.setXfermode(new PorterDuffXfermode(Mode.TARGET); 
    pTouch.setColor(Color.TRANSPARENT);
    pTouch.setMaskFilter(new BlurMaskFilter(15, Blur.NORMAL));
    setContentView(new BitMapView(this, mBitmap,mBitmapover));
}

class BitMapView extends View {
    Bitmap mBitmap = null;
    Bitmap mBitmapover = null;

    public BitMapView(Context context, Bitmap bm, Bitmap bmover) {
    super(context);
    mBitmap = bm;
    mBitmapover = bmover;
    }
     @Override
     public boolean onTouchEvent(MotionEvent ev) {

         switch (ev.getAction()) {

             case MotionEvent.ACTION_DOWN: {

                 X = (int) ev.getX();
                 Y = (int) ev.getY();
                 invalidate();

                 break;
             }

             case MotionEvent.ACTION_MOVE: {

                     X = (int) ev.getX();
                     Y = (int) ev.getY();
                     invalidate();
                     break;

             }           

             case MotionEvent.ACTION_UP:

                 break;

         }
         return true;
     }


    @Override
    protected void onDraw(Canvas canvas) {
    // called when view is drawn
    Paint paint = new Paint();
    paint.setFilterBitmap(true);
    // The image will be scaled so it will fill the width, and the
    // height will preserve the image’s aspect ration
/*  double aspectRatio = ((double) mBitmap.getWidth()) / mBitmap.getHeight();
    Rect dest = new Rect(0, 0, this.getWidth(),(int) (this.getHeight() / aspectRatio));
    double aspectRatio2 = ((double) mBitmapover.getWidth()) / mBitmapover.getHeight();
    Rect dest2 = new Rect(0, 0, this.getWidth(),(int) (this.getHeight() / aspectRatio2));
    canvas.drawBitmap(mBitmap, null, dest, paint);
    canvas.drawBitmap(mBitmapover, null, dest2, paint);                    */

    //draw background
    canvas.drawBitmap(mBitmap, 0, 0, null);
    //copy the default overlay into temporary overlay and punch a hole in it                          
    c2.drawBitmap(mBitmapover, 0, 0, null); //exclude this line to show all as you draw
    c2.drawCircle(X, Y, 80, pTouch);
    //draw the overlay over the background  
    canvas.drawBitmap(overlay, 0, 0, null);
    }
}

 }

我怎样才能做到这一点？

Answer 1

onDraw 函数绘制到 View 。你实际上根本不需要这样做。您可以在位图所在的内存中完成这一切。您也在 C2 上绘制另一个位图。您不必在 onDraw() 中将任何内容绘制到 Canvas 上，所做的只是将其绘制到屏幕上。