Using Context with AppCompatActivity

I'm currently working on an Android app, and working with serializing files. I have a method that serializes a Java object into a file that takes a Context parameter. I can retrieve a valid Context object when working in another class, but when I'm on this class that extends AppCompatActivity, I'm not too sure what to do. I tried using getApplicationContext() but that still gives me a null value for the Context.

Here's the base of what I have so far:

public class BookView extends AppCompatActivity { private static Context context; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_book); Book book = Browse.books.get(getIntent().getIntExtra("index", 0)); Browse.book = book; setUpScreen(book); context = getApplicationContext(); } private void setUpChapters(Book book){ ListView chapters = (ListView) findViewById(R.id.chapters); ChapterAdapter adapter = new ChapterAdapter(this, R.layout.row, book.getChapters()); chapters.setAdapter(adapter); if (context != null) { book.serialize(context); } else { System.out.println("Null bookview context"); } chapters.setOnItemClickListener(new AdapterView.OnItemClickListener() { public void onItemClick(AdapterView<?> parent, View view, int position, long id) { Intent myIntent = new Intent(getApplicationContext(), Reader.class); myIntent.putExtra("index", position); startActivity(myIntent); } }); } } 

How do I get a non-null value for context that I can pass into serialize?

1 Answer

You are calling the method first and then you are initializing the context. Change it like this:

context = BookView.this; setUpScreen(book);