How to iterate through all keys of shared preferences?

What you can do is use getAll() method of SharedPreferences and get all the values in Map<String,?> and then you can easily iterate through.

Map<String,?> keys = prefs.getAll();

for(Map.Entry<String,?> entry : keys.entrySet()){
            Log.d("map values",entry.getKey() + ": " + 
                                   entry.getValue().toString());            
 }

For more you can check PrefUtil.java's dump() implementation.