The Problem

Accessing preferences / configuration / settings from Android is actually pretty straightforward as long as you are in an Activity. To read:

// PREFS_FILENAME = "nameOfPrefsFile";

SharedPreferences pref = getSharedPreferences(PREFS_FILENAME,
                              Context.MODE_PRIVATE);

String string = pref.getString("key", "default");
// 1 is the default if key isn't set
int intValue = pref.getInt("intKey", 1); 

// and so on

SharedPreferences is the key class. To write, you also need the SharedPreferences.Editor class, as follows:

// PREFS_FILENAME = "nameOfPrefsFile";
SharedPreferences pref = getSharedPreferences(PREFS_FILENAME,
                              Context.MODE_PRIVATE);
Editor editor = pref.edit();
editor.putString("key", "value");
editor.putInt("intKey", 5);  

// Until you call commit, the changes will not
// be written, so don't forget this step
editor.commit();

In general however, you will need access to settings in more than one activity and it seems a bit wasteful to get these bits littered through the application. Since I am lazy and like to write things just once, I  separated all the prefs stuff into one class called Settings.

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