switch light/dark mode inside the app. IOS

[Brad1111]

I wanted to have a button to switch between light and dark mode. defining 2 types, like :
Light mode : writing in black, white background
Dark mode : writing in white, black background.

Its pretty straightforward to accomplish but the keyboard doesnt change obviously.
The keyboard is either stuck with the config in the plist , or the config of the iphone itself.
But I want to change it dynamically, running the app, click on my button.

Anyone knows please ?