Sharedpreferences android studio error saving data

Question

I saved my data from an numberDecimal edit text using sharedpreference. When I want to get that data in another activity, it always appears as null, so it wasn't saved correctly. Any suggestion?

This is my code from where I save the data :

public void Start(View view) {
    EditText LevelEdit = (EditText) findViewById(R.id.editText_LevelCurrent);
    String User_Level = LevelEdit.getText().toString();
    if (User_Level == "") {
        Toast.makeText(this, "Select a level",
                Toast.LENGTH_LONG).show();

    } else {


        SharedPreferences sharedPref = getPreferences(Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPref.edit();
        editor.putString(GameConstants.StringvalueOfLevel,User_Level);
        editor.commit();


        Intent myIntent = new Intent(Mygame_Menu.this, Mygame.class);
        startActivity(myIntent);
    }
}

Please see this link how to save and get data from `SharedPreferences` https://stackoverflow.com/a/43805317/4097793 — Sukhbir, Jul 26 '18 at 06:54
Check my answer here https://stackoverflow.com/questions/49765921/spinner-with-sharedpreferences/49766781#49766781 — hasan_shaikh, Jul 26 '18 at 07:02

score 1 · Answer 1 · answered Jul 26 '18 at 06:57

i think your condition is wrong and because of that your saving null object in shared preference don't check the string like this if (User_Level == "")the == operator dose not work on the strings in java ! you should use equals method for comparing to String like this "Amir".equals("Amir")

use this instead if (User_Level==null||User_Level.isEmpty())

Mr. Roshan · Answer 2 · 2018-07-26T07:17:51.777

0

You are missing to put sharedPreference name as parameter causes error.

Instead of this

 SharedPreferences sharedPref = getPreferences(Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPref.edit();

Change

SharedPreferences sharedPref = getApplicationContext().getSharedPreferences("sharedPreferenceName",Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPref.edit();

edited Jul 26 '18 at 07:17

answered Jul 26 '18 at 06:53

Mr. Roshan

1,777
13
33

I get compile error: method getPreferences in class Activity cannot be applied to given types; required: int found: String,int reason: actual and formal argument lists differ in length – user9409795 Jul 26 '18 at 07:12
use getApplicationContext() when calling getPreferences("",); – Mr. Roshan Jul 26 '18 at 07:18
check out my answer again – Mr. Roshan Jul 26 '18 at 07:19
what should I write instead of "sharedPreference" ? GameConstants.StringvalueOfLevel or User_Level? – user9409795 Jul 26 '18 at 07:49
sharedPreference is the name of your sharedPreference it's like as table name in database – Mr. Roshan Jul 26 '18 at 08:12

Mohamed Mohaideen AH · Answer 3 · 2018-07-26T08:10:24.657

0

You can't compare string value with int format in if loop. Change

if(User_Level == "")

To

if(User_Level.equals(""))

So it will check the condition as correct. Otherwise above will execute else part even if its null.

EDITED

 private static final String PREFS_NAME = "PREF_LEVEL_DATA";
 private static final String PREFS_KEY = "LEVEL";

 public void SaveLevel(Context context, String level) {

    SharedPreferences settings = context.getSharedPreferences(PREFS_NAME,
            Context.MODE_PRIVATE);
    SharedPreferences.Editor editor = settings.edit();
    editor.putString(PREFS_KEY, level);

    editor.commit();
}

public String RetrieveLevel(Context context) {

    String level;
    SharedPreferences settings = context.getSharedPreferences(PREFS_NAME,
            Context.MODE_PRIVATE);

    if (settings.contains(PREFS_KEY)) {
        level = settings.getString(PREFS_KEY, "");
    } else {
        return "";
    }
    return level;
}

For store a value

SaveLevel(getApplicationContext(), User_Level);

For retreive a value

String level = RetreiveLevel(getApplicationContext());

UPDATED

 EditText LevelEdit = (EditText) findViewById(R.id.editText_LevelCurrent);
 String User_Level = LevelEdit.getText().toString();
 if (User_Level.equals("")) {
    Toast.makeText(this, "Select a level",
            Toast.LENGTH_LONG).show();

 } else {


    SharedPreferences sharedPref = getSharedPreferences("ANY_PREFERENCE_NAME",
        Context.MODE_PRIVATE); //Replace "ANY_PREFERENCE_NAME" as your own string
    SharedPreferences.Editor editor = sharedPref.edit();
    editor.putString(GameConstants.StringvalueOfLevel,User_Level);
    editor.commit();


    Intent myIntent = new Intent(Mygame_Menu.this, Mygame.class);
    startActivity(myIntent);
}

edited Jul 26 '18 at 08:10

answered Jul 26 '18 at 06:57

Mohamed Mohaideen AH

2,527
1
16
24

Thank you, but still the data is not saved – user9409795 Jul 26 '18 at 07:14
Update how you retrieve the data. And also use preference name. See my edits. – Mohamed Mohaideen AH Jul 26 '18 at 07:18
What I write instead of PREFS_NAME, the name of where i save the data or the name of the string i want to save ? ( it returns error by the SharedPreferences settings = context.getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE); – user9409795 Jul 26 '18 at 07:46
PREFS_NAME & PREFS_KEY both are string value. You can replace with your own. You can use same PREFS_NAME for storing mutiple values. And PREFS_KEY is unique for refrence to your storing value. – Mohamed Mohaideen AH Jul 26 '18 at 07:49
PREFS_NAME is the shared preference name where your values are stored in local preferences. You can create n no of preferences names to seperate your groups of data. In single PREFS_NAME you can stored n no of Values with the refrence help of PREFS_KEY. – Mohamed Mohaideen AH Jul 26 '18 at 07:58
So instead of PREFS_NAME I must write GameConstants.StringvalueOfLevel or User_Level ? – user9409795 Jul 26 '18 at 08:07
See my edited & updated part in answer will help you to clear. – Mohamed Mohaideen AH Jul 26 '18 at 08:11
It worked. Thank you a lot :) – user9409795 Jul 26 '18 at 08:26
Welcome glad to help..! Happy Coding :) – Mohamed Mohaideen AH Jul 26 '18 at 08:28

Sharedpreferences android studio error saving data

3 Answers3