Android NDK Beginner's Guide

Time for action – handling keyboard, D-Pad, and trackball, natively

First, let's handle keyboard and trackball events.

1. Open jni/InputHandler.hpp and add keyboard and trackball event handlers:

   #ifndef _PACKT_INPUTHANDLER_HPP_
   #define _PACKT_INPUTHANDLER_HPP_
   
   #include <android/input.h>
   
   namespace packt {
       class InputHandler {
       public:
           virtual ~InputHandler() {};
   
           virtual bool onTouchEvent(AInputEvent* pEvent) = 0;
           virtual bool onKeyboardEvent(AInputEvent* pEvent) = 0;
           virtual bool onTrackballEvent(AInputEvent* pEvent) = 0;
       };
   }
   #endif

2. Update method processInputEvent() inside the existing file jni/EventLoop.cpp to redirect keyboard and trackball events to InputHandler.

   Trackballs and touch events are assimilated to motion events and can be discriminated ...