XferModeTestView.java 文件源码

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

    //创建一个图层，在图层上演示图形混合后的效果
    int sc = canvas.saveLayer(null, mPaint, ALL_SAVE_FLAG);

    canvas.translate(mWidth / 2, mHeight / 2);

    int radius = Math.min(mWidth, mHeight) / 6;
    mPaint.setColor(0xFFFEC336);
    canvas.drawCircle(0, 0, radius, mPaint);

    Xfermode oldMode = mPaint.getXfermode();
    if (mXfermode != null) {
        mPaint.setXfermode(mXfermode);
    }

    int size = Math.min(mWidth, mHeight) / 4;
    mPaint.setColor(0xFF5596FF);
    canvas.drawRect(0, 0, size, size, mPaint);

    mPaint.setXfermode(oldMode);

    canvas.restoreToCount(sc);
}