Question

我正在尝试从片段开始时间选择器片段并在那里接收结果。

public class DataFragment extends Fragment implements TimePickerDialog.OnTimeSetListener{

 @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    //code
    setTodayBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                DialogFragment newFragment = new TimePickerFragment();
                newFragment.show(getFragmentManager(), "timePicker");
            }
        });
    //code

    }

    @Override
    public void onTimeSet(TimePicker timePicker, int i, int i1) {
        //get info here
    }
}

TimePickerFragment：

public class TimePickerFragment extends DialogFragment {

    private TimePickerDialog.OnTimeSetListener mListener;
    private Context context;

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        this.context = context;

        try {
            mListener = (TimePickerDialog.OnTimeSetListener) context;
        } catch (ClassCastException e) {
            throw new ClassCastException(context.toString() + " must implement OnTimeSetListener");
        }
    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        final Calendar c = Calendar.getInstance();
        int hour = c.get(Calendar.HOUR_OF_DAY);
        int minute = c.get(Calendar.MINUTE);
        return new TimePickerDialog(context, mListener, hour, minute, DateFormat.is24HourFormat(context));
    }

}

我明白了：

java.lang.ClassCastException: michlind.com.workcalendar.views.MainActivity@b61773f must implement OnTimeSetListener
                                                                           at ---.com.workcalendar.views.TimePickerFragment.onAttach(TimePickerFragment.java:30)

Answer 1

将TimePickerFragment更改为如下所示：

public class TimePickerFragment extends DialogFragment {

    private TimePickerDialog.OnTimeSetListener mListener;
    private Context context;

    public void setListener(TimePickerDialog.OnTimeSetListener mListener) {
        this.mListener = mListener;
    }

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        this.context = context;
    }



    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        final Calendar c = Calendar.getInstance();
        int hour = c.get(Calendar.HOUR_OF_DAY);
        int minute = c.get(Calendar.MINUTE);
        return new TimePickerDialog(context, mListener, hour, minute, DateFormat.is24HourFormat(context));
    }

}

现在修改你的DataFragment类 -

 @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    //code
    setTodayBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                TimePickerFragment newFragment = new TimePickerFragment();
                newFragment.setListener(this);
                newFragment.show(getFragmentManager(), "timePicker");
            }
        });
    //code

    }

从片段开始时间选择器片段

1 个答案: