SharedPreferences In Android

Data storage always makes an issue for developers, especially for beginners, and also when the data is very small. Android provides a very simple solution for small data and for all the primitive types like “String, byte, int” etc. Let us have a look at the code first. In every project of mine I always make a class, mostly with the name of HelperFunctions, and I put the functions to read and to write the data from the shared preferences.

public class HelperFunctions
{
    static SharedPreferences preferences;

    //Writes data in shared preference
    public static void saveInSharedPreferences(Context context, String key, String value) {
        preferences = PreferenceManager
            .getDefaultSharedPreferences(context);
        SharedPreferences.Editor editor = preferences.edit();
        editor.putString(key, value);
        editor.apply();
    }

    //read from SharedPreference
    public static String readFromSharedPref(Context context, String key) {
        preferences = PreferenceManager
            .getDefaultSharedPreferences(context);
        return preferences.getString(key, null);
    }

}

We are done, as whenever you need to store the data that you used most, you can just write.

HelperFunctions.saveInSharedPreferences(context, Constants.PROFILE_ID, mData);

The data is saved now and similarly you can get it, as shown below.

String userid = HelperFunctions.readFromSharedPref(context, Constants. PROFILE_ID);

Note

In place of the constants, you can write your String “PreferenceName”.

Let’s have a look at the advantages.

 

• In small enterprise apps, you can save the user login credentials to use them in future or to send the data on the server with the user Id etc.
  
• If you have to update the application at the specific time, in the first install of your Application, you can check for Boolean stored SharedPreferences.
  
• Even if you want to pass JSON between the activities, you can easily do this even if you are a beginner.
  The code given above is tested and works fine, when you can copy the code. If you find any improvements, share and help others to write better code.