How to make custom windowBackground theme style work on all Android devices?

Question

I am trying to get all of my activities to have a custom theme style that should look like this:

Answer 1

The key to solving the problem was changing android:windowBackground in the theme to the following:

@drawable/default_background

Notice that I am no longer using @color, but simply a @drawable, the xml for which is below:

It seems that some devices do not support accepting a color for this element.