Android NDK Beginner`s Guide - Second Edition

Time for action – calling C code from Java

Let's create our first native method and call it from the Java side:

1. Open src/com/packtpub/store/Store.java and declare one native method to query the Store. This method returns int with the number of entries in it. There is no need to define a method body:

   package com.packtpub.store;
   
   public class Store {
       static {
           System.loadLibrary("com_packtpub_store_Store");
       }
   
       public native int getCount();
   }

2. Open src/com/packtpub/store/StoreActivity.java and initialize the store. Use its getCount() method value to initialize the application title:

   public class StoreActivity extends Activity {
       ...
       public static class PlaceholderFragment extends Fragment {
           private Store mStore = new Store(); ... public PlaceholderFragment() ...