背景（圖片）在畫布上繪製，同時在上面

Question

@Override protected void onDraw(Canvas canvas) { 

     if (mBitmap != null) { 

      canvas.drawColor(0xFFAAAAAA); 

      canvas.drawBitmap(background,0,0,mBitmapPaint); 

      if(isRelevant){ 
       canvas.drawBitmap(mBitmapLast, 0,0, mBitmapLastPaint); 
      } 

      canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint); 
       canvas.drawPath(mPath, mPaint); 
     } 
    } 

路我已經試過周圍的線路開關

canvas.drawColor(0xFFAAAAAA); 
       canvas.drawBitmap(background,0,0,mBitmapPaint); 

當canvas.drawColor(0xFFAAAAAA);是第二，我的路徑將顯示出來，當我畫他們在屏幕。有沒有辦法讓背景（位圖）顯示在畫布路徑下面？

Answer 1

嘗試在你的路徑的油漆設置Xfermode：

mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_OVER)); // or DST_OVER 

，看到PorterDuff.Mode解釋。