Fix for predictive text

[jooray]

Kivy's default for input boxes changed from "text" to "null" in Kivy 2.1.0. Not specifying it disallowed typing using predictive text keyboards such as Gboard or Swiftkey swiping, which was irritating, when you are typing text messages.

[jooray]

From Kivy documentation:

input_type

The kind of input keyboard to request.

New in version 1.8.0.
Changed in version 2.1.0: Changed default value from text to null. Added null to options.

Warning
As the default value has been changed, you may need to adjust input_type in your code.