title: How to replace a Button's TextView with a custom layout
body: <p>Instead of just a textview on a button, I'd like the button to contain a layout with two TextViews. See the mockup below. When a user uses the button to add a category, I'd like to update the percentage on the right. I have this working with an <em>included</em> layout, but I want to use a button so that the user instinctively knows to click it.</p>
  
  <p><img src="https://i.stack.imgur.com/la90q.png" alt="enter image description here"></p>