Saving Scores on iOS and Android Devices using MonoGame

Question

Quick question, what is the best way to save a game score in a mobile device (iOS and Android) using MonoGame (example would be a Flappy Bird score).

You can also list ways and approaches of saving scores in mobile devices and discuss the pros and cons of each one.

Just like in Android using Java, there are options like using SQLite, Shared Preferences, external and internal storage.

Answer 1

Quick question. What is the best way to save a game score in a mobile device (iOS and Android) using Monogame (example game Flappy Bird score)?

Well there is only 1 way to do it with MonoGame and that is using the IsolatedStorageFile class. All the other approaches you mentioned do not use MonoGame and if you are looking for any Mono solution you should specify so.

Getting an instance of the class. This works the same in MonoGame as it does for XNA.

#if WINDOWS
    IsolatedStorageFile savegameStorage = IsolatedStorageFile.GetUserStoreForDomain();
#else
    IsolatedStorageFile savegameStorage = IsolatedStorageFile.GetUserStoreForApplication();
#endif    

How to read data from a file.

protected override void OnExiting(object sender, System.EventArgs args)
{
    // Save the game state (in this case, the typed text).
    IsolatedStorageFile savegameStorage = IsolatedStorageFile.GetUserStoreForApplication();

    // open isolated storage, and write the savefile.
    IsolatedStorageFileStream fs = null;
    fs = savegameStorage.OpenFile(SAVEFILENAME, System.IO.FileMode.Create);
    if (fs != null)
    {
        // just overwrite the existing info for this example.
        fs.WriteByte(gameState); // a single byte
        if ((typedText != null) && (typedText.Length > 0))
        {
            fs.Write(System.Text.Encoding.UTF8.GetBytes(typedText), 0, typedText.Length);
        }
        fs.Close();
    }

    base.OnExiting(sender, args);
}

How to write to a file.

protected override void Initialize()
{
    gameState = 0;

    IsolatedStorageFile savegameStorage = IsolatedStorageFile.GetUserStoreForApplication();

    // open isolated storage, and write the savefile.
    if(savegameStorage.FileExists(SAVEFILENAME))
    {
        IsolatedStorageFileStream fs = null;
        try
        {
            fs = savegameStorage.OpenFile(SAVEFILENAME, System.IO.FileMode.Open);
        }
        catch (IsolatedStorageException e)
        {
            // The file couldn't be opened, even though it's there.
            // You can use this knowledge to display an error message
            // for the user (beyond the scope of this example).
        }

        if (fs != null)
        {
            // Reload the last state of the game.  This consists of the UI mode
            // and any text that was typed on the keyboard input screen. 
            byte[] saveBytes = new byte[256];
            int count = fs.Read(saveBytes, 0, 256);
            if (count > 0)
            {
                // the first byte is the mode, the rest is the string.
                gameState = saveBytes[0];
                if (count > 1)
                {
                    typedText = System.Text.Encoding.UTF8.GetString(saveBytes, 1, count - 1);
                }
                fs.Close();
            }
        }
    }

    base.Initialize();
}

Answer 2

I'm using xamarin on windows If you want to keep it simple this worked for me for reading 1 number:

IsolatedStorageFile savegameStorage = IsolatedStorageFile.GetUserStoreForDomain();
    int high_score;
if (savegameStorage.FileExists("high_score.txt")) 
        {
            IsolatedStorageFileStream isoStream = new IsolatedStorageFileStream ("high_score.txt", FileMode.OpenOrCreate,FileAccess.Read);
            using (StreamReader sr = new StreamReader (isoStream)) 
            {
                high_score = int.Parse (sr.ReadLine ());
            }   
        } 
        else
            high_score = 0;
    }

And this for saving , when you die:

if (player1.score > high_score) 
                {
                    IsolatedStorageFileStream isoStream = new IsolatedStorageFileStream ("high_score.txt", FileMode.OpenOrCreate,FileAccess.Write);
                    using (StreamWriter sw = new StreamWriter(isoStream)) 
                    {
                        sw.Flush ();
                        sw.WriteLine (player1.score.ToString ());
                    }