Android构造函数参数错误。无法初始化对象。

Question

我正在尝试使用日期选择器将用户输入反馈回某些文本字段。我正在使用Date选择器对象和监听器。我收到一条错误，指出'无法找到符号变量MyListener。在线：

    DatePickerFragment datePicker = new DatePickerFragment(MyListener);

如果我用'this'替换'MyListner'，我会收到此消息

  

“错误：类DatePickerFragment中的构造函数DatePickerFragment   不能适用于给定的类型;必需：NewClutch.MyListener   发现：NewClutch原因：实际参数NewClutch无法转换   通过方法调用转换“

到NewClutch.MyListener

public static class DatePickerFragment extends DialogFragment
    implements DatePickerDialog.OnDateSetListener {
    private MyListener listener;
    public DatePickerFragment(MyListener listener){
        this.listener = listener;
    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        // Use the current date as the default date in the picker
        final Calendar c = Calendar.getInstance();
        int year = c.get(Calendar.YEAR);
        int month = c.get(Calendar.MONTH);
        int day = c.get(Calendar.DAY_OF_MONTH);

        // Create a new instance of DatePickerDialog and return it
        return new DatePickerDialog(getActivity(), this, year, month, day);
    }
    int selectedDate;
    View targetView;
    public void onDateSet(DatePicker view, int year, int month, int day) {
        // Do something with the date chosen by the user
        selectedDate = day+month+year;
        if(listener!=null){
            listener.theDateHasChanged(selectedDate, targetView);
        }
    }
    public int getSelectedDate() {
        return selectedDate;
    }

    public int setTargetBox(View view) {
        targetView = view;
    }
}
/* close datePickerFragment class */
public void showDatePickerDialog(View view ) {
    DatePickerFragment datePicker = new DatePickerFragment(this);
    datePicker.setTargetBox(view);
    datePicker.show(getFragmentManager(), "datePicker");
    //int output = ((DatePickerFragment)datePicker).getSelectedDate();

    }
public class MyListener {
    public void theDateHasChanged(int selectedDate, View targetView) {
        if(targetView.getId() == R.id.clutch_date_laid_box)
        {
            // --- find the text view --
            TextView txtView = (TextView) findViewById(R.id.date_two_box);
            // -- change text size --
            txtView.setText(selectedDate);
            return;
        }
        if(targetView.getId() == R.id.clutch_name_box)
        {
            // --- find the text view --
            TextView txtView = (TextView) findViewById(R.id.date_one_box);
            // -- change text size --
            txtView.setText(selectedDate);
            return;
        }
    }
}