在RectF Android的交集中透明填充

Question

I have customized button and Im filling Button Color using onDraw and Canvas.. Suppose my Button Parameters(Left,Top,Right,Bottom) are (0,0,200,200) then for the part(20,20,180,180) I want this part transparent and other part with gradient color..

  @Override
            protected void onDraw(Canvas canvas) {
                // TODO Auto-generated method stub
                super.onDraw(canvas);
                int[] iColor = {
                        CommonFunctions
                                .getLightColor(bAppointments.getSrtStatus(), 255),
                        CommonFunctions.getColor(bAppointments.getSrtStatus(), 255) };

                int[] gapColor = { Color.argb(255, 255, 255, 255),
                        Color.argb(255, 255, 255, 255) };

                float[] iPos = {
                        0,
                        (canvas.getClipBounds().bottom - canvas.getClipBounds().top) / 2 };

                LinearGradient lGradient = new LinearGradient(
                        canvas.getClipBounds().right - canvas.getClipBounds().left,
                        canvas.getClipBounds().top, canvas.getClipBounds().right
                                - canvas.getClipBounds().left,
                        canvas.getClipBounds().bottom, iColor, iPos,
                        Shader.TileMode.CLAMP);

    mPaint.setAlpha(0xBB);
                mPaint.setShader(lGradient);
                mPaint.setStyle(Style.FILL);
    mRectF.set(canvas.getClipBounds().left + 2,
                        canvas.getClipBounds().top + 2,
                        canvas.getClipBounds().right - 2,
                        canvas.getClipBounds().bottom - 6);
                canvas.drawRoundRect(mRectF, rectCurve, rectCurve, mPaint);
}

Currently my Layout Look Like

Answer 1

for now..I have done it using temporary solution.. I filled transparent to the button first.. then I divided the Button Canvas into 5 part..

Top Part, Left Part, Gap Part, Right Part and Bottom Part.. n I filled that part using the same Paint object..

Still waiting for the good solution..

Thanks.