Developing Keyboard

I created a keyboard for android, the keys are working right, but do not know how to add it as default for my device, ie, when I click on the EditText WhatsApp for example, instead of up the keyboard android, show my keyboard to type.

Go to settings -> language and input -> set the default keyboard to yours.

No, this I know.
I created the keyboard but’re working with a EditText inside the Activity keyboard. I would like to know how to add the keyboard on this list of “Language and Input”.

You need to extend the IME, InputMethodService. Creating an Input Method | Android Developers Blog

Well, head over to the settings>input and Keyboard>Select the Keyboard app which you have just installed it will change the default keyboard to what you are using.