Android画布绘制半透明图形，因此它们相互叠加

Question

在画布上，我绘制了彼此覆盖的数字以获得我想要的结果。它们的透明度为128，覆盖区域的颜色为多个。我需要一种颜色的整体图形。如何解决？

protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        Paint paint = new Paint();
        paint.setColor(Color.GREEN);

        Path path =  new Path();
        path.moveTo(margin,0);
        path.lineTo(middleWidth+pieceWidth,0);
        path.lineTo(middleWidth-pieceWidth,height);
        path.lineTo(margin, height);
        path.lineTo(margin, 0);

        Path path1 = new Path();
        path1.moveTo(middleWidth+pieceWidth+interval,0);
        path1.lineTo(middleWidth-pieceWidth+interval,height);
        path1.lineTo(width-margin,height);
        path1.lineTo(width-margin,0);
        path1.lineTo(middleWidth+pieceWidth+interval,0);


        RectF rect = new RectF();
        rect.set(0,0,middleWidth-pieceWidth,height);

        RectF rect1 = new RectF();
        rect1.set(middleWidth+pieceWidth,0,width,height);


        paint.setStyle(Paint.Style.FILL);

        paint.setColor(leftColor);
        paint.setAlpha(128);
        canvas.drawPath(path, paint);

        paint.setColor(rightColor);
        paint.setAlpha(128);
        canvas.drawPath(path1, paint);
        paint.setAlpha(128);
        paint.setStyle(Paint.Style.FILL);
        canvas.drawRoundRect(rect, corners, corners, paint);
        canvas.drawRoundRect(rect1, corners, corners, paint);
    }

结果是：

Result picture