I'm trying to store a set of strings using the
Set<String> s = sharedPrefs.getStringSet("key", new HashSet<String>());
SharedPreferences.Editor editor = sharedPrefs.edit();
This "problem" is documented on
SharedPreferences.getStringSet returns a reference of the stored HashSet object
SharedPreferences. When you add elements to this object, they are added in fact inside the
That is ok, but the problem comes when you try to store it: Android compares the modified HashSet that you are trying to save using
SharedPreferences.Editor.putStringSet with the current one stored on the
SharedPreference, and both are the same object!!!
A possible solution is to make a copy of the
Set<String> returned by the
Set<String> s = new HashSet<String>(sharedPrefs.getStringSet("key", new HashSet<String>()));
s a different object, and the strings added to
s will not be added to the set stored inside the
Other workaround that will work is to use the same
SharedPreferences.Editor transaction to store another simpler preference (like an integer or boolean), the only thing you need is to force that the stored value are different on each transaction (for example, you could store the string set size).