Using Application context everywhere?

yanchenko picture yanchenko · Jun 12, 2009 · Viewed 300.8k times · Source

In an Android app, is there anything wrong with the following approach:

public class MyApp extends android.app.Application {

    private static MyApp instance;

    public MyApp() {
        instance = this;
    }

    public static Context getContext() {
        return instance;
    }

}

and pass it everywhere (e.g. SQLiteOpenHelper) where context is required (and not leaking of course)?

Answer

Reto Meier picture Reto Meier · Jun 12, 2009

There are a couple of potential problems with this approach, though in a lot of circumstances (such as your example) it will work well.

In particular you should be careful when dealing with anything that deals with the GUI that requires a Context. For example, if you pass the application Context into the LayoutInflater you will get an Exception. Generally speaking, your approach is excellent: it's good practice to use an Activity's Context within that Activity, and the Application Context when passing a context beyond the scope of an Activity to avoid memory leaks.

Also, as an alternative to your pattern you can use the shortcut of calling getApplicationContext() on a Context object (such as an Activity) to get the Application Context.