问题：

Question

我正在制作一个Dialog。在Initial状态中，DatePickerFragment显示当前日期。然后我将该日期设置为我的TextView。它工作正常。

以下是代码：

DatePickerFragment类

public class DatePickerFragment : DialogFragment,
                                  DatePickerDialog.IOnDateSetListener
    {
        public static readonly string TAG = "X:" + typeof(DatePickerFragment).Name.ToUpper();

        // Initialize this value to prevent NullReferenceExceptions.
        Action<DateTime> _dateSelectedHandler = delegate { };

        public static DatePickerFragment NewInstance(Action<DateTime> onDateSelected)
        {
            DatePickerFragment frag = new DatePickerFragment();
            frag._dateSelectedHandler = onDateSelected;

            return frag;
        }

        public override Dialog OnCreateDialog(Bundle savedInstanceState)
        {
            DateTime currently = DateTime.Now;
            DatePickerDialog dialog = new DatePickerDialog(Activity,
                                                           this,
                                                           currently.Year,
                                                           currently.Month - 1,
                                                           currently.Day);
            return dialog;
        }

        public void OnDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth)
        {
            DateTime selectedDate = new DateTime(year, monthOfYear + 1, dayOfMonth);

            _dateSelectedHandler(selectedDate);

        }
    }

on Activity在我的对话框中使用这种方式。

txt_selectDate = dialog.FindViewById<TextView>(Resource.Id.txt_selectDate);
                        DateTime cuurently = DateTime.Now;
                        txt_selectDate.Text = cuurently.ToString("dd/MM/yyyy",CultureInfo.InvariantCulture);
                        dialog.Show();

                        var select_date = dialog.FindViewById<ImageView>(Resource.Id.select_date);
                        select_date.Click += SelectDate_Click;

并创建像这样的点击方法

void SelectDate_Click(object sender, EventArgs e)
            {
                DatePickerFragment frag = DatePickerFragment.NewInstance(delegate (DateTime time)
                    {
                        var pickupDate = time.ToString("yyyy-MM-dd'T'HH:mm:ss'Z'", CultureInfo.InvariantCulture);
                        txt_selectDate.Text = time.ToString("dd/MM/yyyy", CultureInfo.InvariantCulture);

                    });

                frag.Show(context.FragmentManager, DatePickerFragment.TAG);
            }

问题：

现在当我再次点击拾取新日期时，DatePickerFragment显示当前日期而不是上一个选定日期。那么我可以将上一个日期设置为DatePickerFragment吗？

任何帮助都要得到赞赏。

更新：

添加参数后，它会给出此响应。

Answer 1

我没有使用DatePickerFragment，而是按照以下方式使用DatePickerDialog来解决我的问题。

以这种方式显示DatePicker

ddtime = new DatePickerDialog(context, OnDateSet, DateTime.Today.Year, DateTime.Today.Month - 1,
                                                     DateTime.Today.Day
                                                             );

                            ddtime.DatePicker.DateTime = selected_Date;
                            ddtime.SetTitle("");
                            ddtime.Show();

它的方法OnDataSet就像这样

async void OnDateSet(object sender, DatePickerDialog.DateSetEventArgs e)
            {
                default_date = e.Date.Year + "/" + e.Date.Month + "/" + e.Date.Day;
                txt_selectDate.Text = e.Date.Day + "/" + e.Date.Month + "/" + e.Date.Year;
                selected_Date = e.Date;
            }

最后我的selected_Date在datePicker中设置如下

ddtime.DatePicker.DateTime = selected_Date;

有没有办法在Android中的DatePickerFragment中设置日期（Xamarin）

问题：

1 个答案: