I want a Layout like this:

But my code doesn\'t work. I can\'t achieve this Layout, and I don\'t
You don't need to use gravity or the inner LinearLayout at all for this. Instead use layout_alignParentTop, layout_alignParentLeft, layout_alignParentRight, layout_alignParentBottom, layout_centerInParent and layout_centerVertical on the children.
It might be useful for you to go through the RelativeLayout tutorial.