public class WaterActivity extends Activity {


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_water);

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab_water1);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                EditText editTextDate = (EditText) findViewById(R.id.editText_water_date);
                EditText editTextUtilites = (EditText) findViewById(R.id.editText_water_utilites);
                EditText editTextUtilites2 = (EditText) findViewById(R.id.editText_water_utilites2);
                EditText editTextEmail = (EditText) findViewById(R.id.editText_water_email);

                WaterDataModel item = new WaterDataModel();

                item.setDate(editTextDate.getText().toString());
                item.setUtilites2(editTextUtilites2.getText().toString());
                item.setUtilites( editTextUtilites.getText().toString());
                item.setEmail(editTextEmail.getText().toString());

                cacheToPreferenceWaterDataModelItem(item);

                Intent intent = new Intent(WaterActivity.this, MainActivity.class);
                startActivity(intent);
            }
        });
   }

    void cacheToPreferenceWaterDataModelItem(WaterDataModel item) {
        Array items = getCachedWaterDataModelItems();

        ArrayList<WaterDataModel> arrayList = new ArrayList<WaterDataModel>(Arrays.asList(item));
        arrayList.add(item);

//        Array updatedItems = arrayList.toArray();



        SharedPreferences appSharedPrefs = PreferenceManager
                .getDefaultSharedPreferences(this.getApplicationContext());
        SharedPreferences.Editor prefsEditor = appSharedPrefs.edit();
        Gson gson = new Gson();
        String json = gson.toJson(arrayList);
        prefsEditor.putString("cachedWaterDataModelItems", json);
                prefsEditor.commit();
    }

    Array getCachedWaterDataModelItems() {   //ВОЗВРАЩАЕТ МАССИВ

        SharedPreferences appSharedPrefs = PreferenceManager
                .getDefaultSharedPreferences(this.getApplicationContext());
        Gson gson = new Gson();
        String json = appSharedPrefs.getString("cachedWaterDataModelItems", "");
        Array items = gson.fromJson(json, Array.class);

        return  items;
    }

}