change focus between two views in split view

Let's say that I have two apps running beside each other is splitview , How to change the focus from one to the other , e.g. if I am using two editors, If I am writing to editor 1, after the shortcut I will be writing in editor 2. I know how to do it by the mouse but how to do it using only keyboard shortcuts?

Thanks in advance

I'm going to post a different question to see if there's a way to write an applescript/keyboard maestro macro to hack this together using system properties (since I'm sure OS X is storing somewhere variables that encode which apps are splitting which space, what the current space is, and what the current focus is). But this answer to the question Switch focus in split view makes it seem like there is no way to do this by default either across 2 different apps or within two instances of the same app.

In it they suggest using ⌘` for moving between two instances of the same app, and the closest by default would be ⌘⇥ for different apps.