"prefs" showing up as NOT used?

Question

I'm trying to save a string in preference by adding it to the editor when a user press a button. Then i'm trying to retreieve the strings from the preference and turn it into an arrayList.

in onCreate

 this.context = getApplicationContext();
        SharedPreferences prefs = getSharedPreferences(SHARED_PREFS_FILE, Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = prefs.edit();

         int size = updatableList.size();
         editor.putInt("list_size", size);

         for (int i = 0; i < size; i++) {
             ((SharedPreferences) editor).getString("list_"+i, updatableList.get(i));
         }       
         editor.commit();

Later in the application

               updatableList.add(picturePath);
               i=i++;   
               //saving path to preference********
             SharedPreferences prefs = getSharedPreferences(SHARED_PREFS_FILE, Context.MODE_PRIVATE);
             ((Editor) editor).putString("list_"+i, picturePath);
             editor.commit();

It says the prefs later in the application is unused which i think is odd because i thought it told it to putString. The application crashes when it gets to there. Why does my prefs later in the application get used?

Answer 1

I see a main problem here and it's the following line:

i=i++;

This will not change i at all. You're telling it to increment i but at the same time setting i to the value prior to incrementing it. i++; is what you want.

Also I'd suggest using SharedPreferences.Editor.putStringSet() instead of putString() - that way you don't need to care about size and so on.