Logout clear SharedPreferences

Question

I have a login page that saves username and password to SharedPreferences. I have another Activity class that includes a logo

Answer 1

Try this !

logout.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View view) {
            // Launching News Feed Screen

             SharedPreferences preferences =getSharedPreferences("loginPrefs",Context.MODE_PRIVATE);
             SharedPreferences.Editor editor = preferences.edit();
             editor.clear();
             editor.apply();
             finish();
 });

Answer 2

I think you have a trouble in understanding Shared preferences in android .

According to official documentation

To get a SharedPreferences object for your application, use one of two methods:

getSharedPreferences() - Use this if you need multiple preferences files identified by name, which you specify with the first parameter.

getPreferences() - Use this if you need only one preferences file for your Activity. Because this will be the only preferences file for your Activity, you don't supply a name.

You should have a Context for using both the above methods .

Also Shared preferences are stored asa key value pair , so clearing should mean that you set the values to some empty string.

For more details , and better explanation you can read here http://developer.android.com/guide/topics/data/data-storage.html#pref and http://www.vogella.com/tutorials/AndroidFileBasedPersistence/article.html

Hope this will help.

Cheers!

Answer 3

In Kotlin you can use this code to clear the sharedpreference data

private val sharedPref = "sharedpreference"

val sharedPreferences: SharedPreferences = context.getSharedPreferences(sharedPref, Context.MODE_PRIVATE)
            val editor = sharedPreferences.edit()
            editor.clear()
            editor.apply()

Answer 4

It as Simple. Like you save your data in SharedPrefernce

SharedPreferences sp = getSharedPreferences("MYKEY",0);
SharedPreferences.Editor editor = sp.edit();
editor.putString("username" , username);
editor.putString("password" , password);

Now you can retrieve as in any class of your app like,

SharedPreferences sp = getSharedPreferences("MYKEY",0);
String uname = sp.getString("username");
String pwd = sp.getString("password");

And for clear your username and password

editor.clear();
editor.commit();

or

editor.remove("username");
editor.remove("password");
editor.commit();

Answer 5

SharedPreferences mPrefs = PreferenceManager.getDefaultSharedPreferences(this);
SharedPreferences.Editor editor = mPrefs.edit();
editor.clear();
editor.commit();

Answer 6

Why not write a SharedPreference utility class. This can be accessed from both the activities.