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android - Shared Preferences reset data when app is force closed or device is restarted

I'm developing an application in which I'm storing username and password in SharedPreferences. All things are working fine for me, storing as well as retrieving the values. But I discovered that when I restart the device or the app is force closed the value stored in SharedPreferences is reset. And when I again launch my app I get null values in SharedPreferences key. Here, is what I'm doing for storing the values:

SharedPreferences emailLoginSP;

emailLoginSP = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
emailLoginSP.edit().putString("prefEmailId", email_text).commit();
emailLoginSP.edit().putString("prefUserId", userIDToken).commit();
emailLoginSP.edit().putString("prefAccess_token", accessToken).commit();

Intent i = new Intent(LoginWithEmail.this,UserInfoActivity.class);
i.putExtra("acess_token", accessToken);
i.putExtra("user_id", userIDToken);
i.putExtra("emailID", email_text);
startActivity(i);

And, this is how I'm retriving it:

SharedPreferences emailLoginSP = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());

loginEmail = emailLoginSP.getString("prefEmailId", null);
loginUserId = emailLoginSP.getString("prefUserId", null);
loginAccessToken = emailLoginSP.getString("prefAccess_token", null);

All things are working fine till now. Again I'm stating my problem that I get null values when I force close or restart my device. Can we store it permanently in the app memory? Or, I'm doing something wrong here?

Any help will be appreciated.

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by (71.8m points)

I have a login screen and wanted the app to appear as if it's remained "logged in" at the internal screen after the app is closed/destroyed/phone call/etc.

I have a Preferences Object to save values following Login or Register. I read preference values in all the key screen onResume() methods.

After login (for example):

SharedPreferences app_preferences = PreferenceManager.getDefaultSharedPreferences(activity);
SharedPreferences.Editor editor = app_preferences.edit();
editor.putString("sessionId", application.currentSessionId);
editor.putString("userId", application.currentUserId);
editor.putString("userEmail", application.currentUserEmail);
editor.putString("siteUserId", application.currentSiteUserId);
editor.commit();

Within onResume() of Activities: (ie, within internal screens)

SharedPreferences app_preferences = PreferenceManager.getDefaultSharedPreferences(activity);
application.currentSessionId = app_preferences.getString("sessionId", "");
application.currentUserId = app_preferences.getString("userId", "");
application.currentUserEmail = app_preferences.getString("userEmail", "");
application.currentSiteUserId = app_preferences.getString("siteUserId", "");

Note. I have application "global" variables, ie, application.currentSessionId, you can just substitute your variables

Try something similar maybe your not saving or retrieving the values correctly because SharePreferences should work


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