Refactor MyInputMethodService

[nkrusch]

The entire keyboard is essentially contained within this 1 class. With more and more features the class is becoming increasingly challenging to manage and needs to be refactored into more manageable (smaller) classes.

One possibility is to make a class for each keyboard view: qwerty, azerty, numeric and symbolic keyboards and each of these classes manages its own functionality. For example shift key is only relevant in the alphabetic keyboard.

The first task here is to think about what would be the ideal way to organize this functionality. The above maybe not be ideal long term so do not limit to that organization alone. This is a low priority task.

[NA0341]

You could ask the developers of other projects how they implemented their stuff (such as OpenBoard, Unexpected Keyboard or Simple Keyboard by SimpleMobileTools).