Обратная передача данных в ListView

public class RepeatListItem {
 
    private boolean mIsChecked;
    public void setIsChecked(final boolean isChecked){
        mIsChecked = isChecked;
    }
    public boolean getIsChecked() {
        return mIsChecked;
    }
 
    private String mName;
    public void setName(final String name){
        mName = name;
    }
    public String getName() {
        return mName;
    }
 
    public RepeatListItem() {}
 
    public RepeatListItem(final String name, final boolean isChecked){
        mName = name;
        mIsChecked = isChecked;
    }
}

public class RepeatListAdapter extends ArrayAdapter<RepeatListItem> {
 
    private LayoutInflater mInflater;
    private int mLayout;
    private List<RepeatListItem> mRepeats;
 
    public RepeatListAdapter(@NonNull final Context context, final int resource, final List<RepeatListItem> repeat) {
        super(context, resource, repeat);
        mRepeats = repeat;
        mLayout = resource;
        mInflater = LayoutInflater.from(context);
    }
 
    public View getView(int position, View convertView, ViewGroup parent) {
 
        View view = mInflater.inflate(this.mLayout, parent, false);
 
        AppCompatCheckBox checkBox = (AppCompatCheckBox) view.findViewById(R.id.checkBox);
 
        RepeatListItem repeatListItem = mRepeats.get(position);
 
        checkBox.setChecked(repeatListItem.getIsChecked());
        checkBox.setText(repeatListItem.getName());
 
        return view;
    }
}

public class SelectRepeatActivity extends AppCompatActivity {
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_select_repeat);
 
        Intent intent = this.getIntent();
        int repeat = intent.getIntExtra("repeat", 0);
        ListView lv = (ListView)findViewById(R.id.repeatListView);
        List<RepeatListItem> repeats = new ArrayList<RepeatListItem>();
        final String[] weekDays = getResources().getStringArray(R.array.weekDays);
        for(int i = 0; i < weekDays.length; i++){
            repeats.add(i, new RepeatListItem(weekDays[i], WeekDays.isDayInSet(repeat, i)));
        }
        RepeatListAdapter adapter = new RepeatListAdapter(this,
            R.layout.repeat_list_item, repeats);
        lv.setAdapter(adapter);
    }
...
 
    private int packDays() {
        int result = 0;
        ListView lv = (ListView)findViewById(R.id.repeatListView);
        Adapter adpater = lv.getAdapter();
        for (int i = 0; i < lv.getCount(); i++){
            RepeatListItem item = (RepeatListItem) lv.getItemAtPosition(i);
            if (item.getIsChecked() == true)
                result |= WeekDays.getDayCode(i);
            else
                result &= ~WeekDays.getDayCode(i);
        }
        return result;
    }
}