Here’s a simple example:

(You may want to throw that whole block in a ScrollView for more obvious results)

So what you have above is pretty straightforward. You have a container with wrap_content for height. It has 2 children, one is at a fixed height of 10000dp, and the other is set to match_parent. As expected, the parent is expanded to 10000dp in height, as you can see by the red background. However, the second sibling, whose height should “match parent”, clearly does not do that – you’ll notice the orange background of that second sibling exists only as tall enough as is required to render the TextView.

There are simple ways around this – for example, you could write a LargestChildLayout pretty simply:

Or if you wish to use provided components, a ConstraintLayout can achieve it as well:

I suspect a RelativeLayout might work as well, with layout_alignParentTop and layout_alignParentBottom both set to true, but haven’t tried.