Storing a high score in Android app

Question

I have an app which displays the score on the main screen but this sets to zero every time a new game is started. What I want it to do is store that score and only change if the next score is higher, hence it being the highest score.

At the moment a hitCount method is deployed which a finish() method utilises to show the score from the game activity to the main activity.

The finish() method is below:

public void finish(){

    Intent returnIntent = new Intent();
    returnIntent.putExtra("GAME_SCORE", gameView.getHitCount());
    setResult(RESULT_OK, returnIntent);
    super.finish();

}

In the MainMenu class, the following onActivityResult() method is used to get the score to display on the main screen:

protected void onActivityResult(int requestCode, int resultCode, Intent retIntent) {
    // Check which request we're responding to
    if (requestCode == SCORE_REQUEST_CODE) {
        // Make sure the request was successful
        if (resultCode == RESULT_OK) {
            if (retIntent.hasExtra("GAME_SCORE")) {
                int scoreFromGame = retIntent.getExtras().getInt("GAME_SCORE");
                tvScore.setText(Integer.toString(scoreFromGame));
                //highScore.setText(Integer.toString(scoreFromGame));
            }
        }   
    }

}

Now, I know I must use something like shared preference to have any chance of storing the score and replacing it with a higher number when achieved but I can't figure out how and where.

As always, any help greatly appreciated.

Thanks

Possible duplicate of [How to use SharedPreferences in Android to store, fetch and edit values](http://stackoverflow.com/questions/3624280/how-to-use-sharedpreferences-in-android-to-store-fetch-and-edit-values) — OneCricketeer, Apr 18 '17 at 20:48
You can access SharedPreferences anywhere you have a Context (like an Activity) — OneCricketeer, Apr 18 '17 at 20:49

Sky · Answer 1 · 2017-04-18T21:37:40.310

1

Put the following into your onCreate method to read the high score.

SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
// Read the high score from Shared Preference
int mHighScore = sharedPref.getInt(getString(R.string.high_score), 0);

Update your high score using Shared Preference:

protected void onActivityResult(int requestCode, int resultCode, Intent retIntent) {
// Check which request we're responding to
    if (requestCode == SCORE_REQUEST_CODE) {
        // Make sure the request was successful
        if (resultCode == RESULT_OK) {
            if (retIntent.hasExtra("GAME_SCORE")) {
                int scoreFromGame = retIntent.getExtras().getInt("GAME_SCORE");
                tvScore.setText(Integer.toString(scoreFromGame));
                //highScore.setText(Integer.toString(scoreFromGame));

                // Write the new high score to Shared Preference
                SharedPreferences.Editor editor = sharedPref.edit();
                if (scoreFromGame > mHighScore) {
                    editor.putInt(getString(R.string.high_score), scoreFromGame);
                    editor.commit();
                }
            }
        }   
    }
}

edited Apr 18 '17 at 21:37

answered Apr 18 '17 at 20:52

Sky

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I can understand this structure but not where exactly it should go – Phil Adams Apr 18 '17 at 21:00
Thanks for that. Although I'm now getting the error - Operator '>' cannot be applied to 'int', 'android.widget.TextView' – Phil Adams Apr 18 '17 at 21:24
I know what's wrong. One of your TextView has the same name "highScore" as the "highScore" int variable. Rename the variable and that should be fixed. – Sky Apr 18 '17 at 21:40
It's stopped that problem but the app is just crashing on start-up. It's just getting a bit messy now and I'm about to give up on this and try and think of a new angle – Phil Adams Apr 18 '17 at 22:02
What is your new angle? – Sky Apr 19 '17 at 07:03
I don't know. Maybe not bother with it at all as I can't seem to work it out – Phil Adams Apr 19 '17 at 07:43
Let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/142050/discussion-between-skyluke-and-phil-adams). – Sky Apr 19 '17 at 07:52
Maybe available in about half an hour? – Phil Adams Apr 19 '17 at 07:59

score 0 · Answer 2 · answered Apr 18 '17 at 21:01

You should definitively read about SharedPreferences and look at the link given in the comments. If you want a quick solution for now:

MainActivity.java

SharedPreferences prefs;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // Set highscore text on start
    prefs = PreferenceManager.getDefaultSharedPreferences(this);
    int highscore = prefs.getInt(PreferenceHelper.KEY_HIGHSCORE, 0);
    tvHighScore.setText(Integer.toString(highscore));
}

protected void onActivityResult(int requestCode, int resultCode, Intent retIntent) {
    // Check which request we're responding to
    if (requestCode == SCORE_REQUEST_CODE) {
        // Make sure the request was successful
        if (resultCode == RESULT_OK) {
            if (retIntent.hasExtra("GAME_SCORE")) {
                int scoreFromGame = retIntent.getExtras().getInt("GAME_SCORE");
                tvScore.setText(Integer.toString(scoreFromGame));

                int highscore = prefs.getInt(PreferenceHelper.KEY_HIGHSCORE, 0);  // Get highscore stored in prefs
                if (scoreFromGame > highscore) {
                    // Update text and save new highscore
                    tvHighScore.setText(Integer.toString(scoreFromGame));
                    prefs.edit().putInt(PreferenceHelper.KEY_HIGHSCORE, scoreFromGame).apply();
                }
            }
        }
    }

}

PreferenceHelper.java

public final class PreferenceHelper {

    public static final String KEY_HIGHSCORE = "highscore";

}

You don't have to use the PreferenceHelper class, but it's a good practice.

Storing a high score in Android app

2 Answers2