How can I get activity coordination on screen

I want to start activity B in a standalone stack, and its locate at the center of activity A.
I find the follow method to launch activity B in new statck, and set it’s coordination:

Intent intent = new Intent(mContext, ActivityB.class);
ActivityOptions options = ActivityOptions.makeBasic();
options.setLaunchBounds(new Rect(200,200,1000,800));
mContext.startActivity(intent, options.toBundle());  

But i can’t find method to get coordination of activity A. I can’t calculate the correct coordination of activity B. Can anyone give me a hand?

Hi @lij1591188294,
Could you please elaborate your requirements with a graphical presentation? You may draw it on a paper or just use Paint app. It would be helpful to understand and assist accordingly to resolve your problem.