Home/ Questions/Q 8602191
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-06-12T02:01:15+00:00

I’m trying to write a small bit of binary data as a string to

  • 0

I’m trying to write a small bit of binary data as a string to SharedPreferences. I may be grossly misunderstanding encoding here, but this is what I’m trying to do:

String str = new String("hi there!".getBytes(), "ISO-8859-1");

SharedPreferences p = context.getSharedPreferences("foo", MODE_PRIVATE);
Editor e = p.edit();
e.putString("string", str);
e.putBoolean("worked", true);
e.commit();

... later on after an app restart...

// the shared prefs file will be empty upon the next app start:
SharedPreferences p = context.getSharedPreferences("foo", MODE_PRIVATE);
Log.d(TAG, "String value present?: " + p.getString("string", null)); 
Log.d(TAG, "Boolean flag present?: " + p.getBoolean("worked", false));

The commit() call returns true, everything seems ok. The next time I start this demo app, I read the contents of this shared prefs instance, and it’s completely empty. If I don’t use the “ISO-8859-1” encoding, then everything works as expected, the shared prefs file has the key values in it.

Can shared prefs not work with a string using that encoding?

Thanks

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    SharedPreferences is probably treating the strings as UTF-8 encoded, and you are giving it strings that are ISO-8859-1 encoded. These two encodings are not compatible so that’s probably why you’re seeing this issue.

    Do you have to use ISO-8859-1 encoding? Can you set the encoding to UTF-8 or leave it blank entirely(I believe Java will store it as UTF-16 encoded bytes by default)? This is generally a safer choice to use when you can.

    • 0