畫布上用多種顏色繪製線條

Question

Android開發新手，我的應用程序是用多種顏色從顏色選擇器中選擇畫布（具有位圖）的繪製路徑。之前繪製的路徑顏色正在使用畫布上的新路徑顏色進行更新。任何在幫助我，這是我的代碼.........

@Override 
public void run() { 
    // TODO Auto-generated method stub 
    while (locker) { 
     canvas = null; 
     try { 
      if (!holder.getSurface().isValid()) { 
       continue; 
      } 
      canvas = holder.lockCanvas(); 

      draw(canvas); 

     } finally { 
      if (canvas != null) { 
       holder.unlockCanvasAndPost(canvas); 
      } 
     } 
    } 
} 

@Override 
public boolean onTouchEvent(MotionEvent event) { 
    // synchronized (thread.getSurfaceHolder()) { 
    if (event.getAction() == MotionEvent.ACTION_DOWN) { 
     path = new Path(); 
     path.moveTo(event.getX(), event.getY()); 
     path.lineTo(event.getX(), event.getY()); 
    } else if (event.getAction() == MotionEvent.ACTION_MOVE) { 
     path.lineTo(event.getX(), event.getY()); 
    } else if (event.getAction() == MotionEvent.ACTION_UP) { 
     path.lineTo(event.getX(), event.getY()); 
     paths.add(path); 
    } 
    return true; 
    // } 
} 

/** 
* This method deals with paint-works. Also will paint something in 
* background 
*/ 
private void draw(Canvas canvas) { 
    Bitmap bitmap = BitmapFactory.decodeResource(getResources(), 
      R.drawable.bell); 
    // canvas.drawColor(Color.CYAN); 
    canvas.drawBitmap(bitmap, 20, 20, mPaint); 
    // canvas.drawPath(mPath, mPaint); 
    for (Path path : paths) { 
     // canvas.drawPoint(graphic.x, graphic.y, mPaint); 
     canvas.drawPath(path, mPaint); 
    } 
} 

}

Answer 1

你需要記住每一個路徑它與繪製的顏色。例如，你可以有一個顏色列表（整數），與路徑列表同時填充。然後在你的抽籤方法做到這一點：

private void draw(Canvas canvas) { 
    Bitmap bitmap = BitmapFactory.decodeResource(getResources(), 
      R.drawable.bell); 
    canvas.drawBitmap(bitmap, 20, 20, mPaint); 

    int count = path.size(); 
    for (int i = 0; i < count; i++) { 
     mPaint.setColor(colors.get(i)); 
     canvas.drawPath(paths.get(i), mPaint); 
    } 
}