SharedPreferences putStringSet doesn't work [duplicate]

Answer 1

Remove the key for HashSet in SharedPreferences, commit then add new value.

SharedPreferences ss;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_third);
    ss = getSharedPreferences("db", 0);
    fun();
}

void fun() {
    Log.i("chauster", "1.set = "+ss.getStringSet("set", new HashSet()));

    Button btn = (Button)findViewById(R.id.btn);
    btn.setOnClickListener(new Button.OnClickListener() {

        @Override
        public void onClick(View v) {
            Set hs = ss.getStringSet("set", new HashSet());
            hs.add(String.valueOf(hs.size()+1));
            Log.i(TAG, "list: " + hs.toString());
            Editor edit = ss.edit();
            edit.remove("set");
            edit.commit();
            edit.putStringSet("set", hs);
            Log.i(TAG, "saved: " + edit.commit());

            Log.i("chauster", "2.set = "+ss.getStringSet("set", new HashSet()));
        }
    });
}