How to get selected date when dynamic DateTimepicker change on xamarin form?-CodePudding

I working on a app that needs dynamic fields for filling form. this form may contains multiple timesheets and each timesheet include startDate and finishDate. so how can set property_change on datepicker that creates on runtime?

if (field.Type == "Timesheets"){
DatePicker sDate = new DatePicker();
 sDate.StyleId = field.Name;
  sDate.PropertyChanged  = sDate_changed;

DatePicker fDate = new DatePicker();
 fDate.StyleId = field.Name;
  sDate.PropertyChanged  = fDate_changed;
}



  private async void sDate_changed(object sender, PropertyChangedEventArgs e)
        {

           // here I don't have access to sdate and fdate

        }

CodePudding user response：

that is what the sender parameter does

private async void sDate_changed(object sender, PropertyChangedEventArgs e)
    {
        var picker = (DatePicker)sender;

        // now you can access all the properties of the picker
    }

CodePudding user response：

After checking your code, I recommend you to add event DateSelected for your DatePicker.

replace code:

   sDate.PropertyChanged  = sDate_changed;
   fDate.PropertyChanged  = fDate_changed;

with:

   sDate.DateSelected  = SDate_DateSelected; 
   fDate.DateSelected  = FDate_DateSelected;

// here I don't have access to sdate and fdate

There are two ways to access sdate and fdate.

Method 1(just as Jason posted):

 async void  SDate_DateSelected(object sender, DateChangedEventArgs e)
            {
                var picker = (DatePicker)sender;
                await DisplayAlert("Alert", "selected date is: "   picker.Date, "OK");

            }

Method 2:

Since you have defined new variables for two DatePicker(sdate and fdate) , you can use the two variables(sdate and fdate) to access the selected date.

Please refer to the following code:

        sDate.DateSelected  = SDate_DateSelected; 
        fDate.DateSelected  = FDate_DateSelected;

        //method 2
        void Recalculate()
        {
            TimeSpan timeSpan = fDate.Date - sDate.Date;

            mLabel.Text = String.Format("{0} day{1} between dates",
                                                timeSpan.Days, timeSpan.Days == 1 ? "" : "s");
        }

         async void  SDate_DateSelected(object sender, DateChangedEventArgs e)
        {
            var picker = (DatePicker)sender;
            await DisplayAlert("Alert", "SDate_DateSelected : "   picker.Date, "OK");

            //Recalculate();
        }

        async void FDate_DateSelected(object sender, DateChangedEventArgs e)
        {
            var picker = (DatePicker)sender;
            await DisplayAlert("Alert", " FDate_DateSelected : "   picker.Date, "OK");

            //Recalculate();
        }

Note:

I find that your code variable is being used incorrectly,please replace the following code:

DatePicker fDate = new DatePicker();
fDate.StyleId = field.Name;
sDate.PropertyChanged  = fDate_changed;

with

DatePicker fDate = new DatePicker();
fDate.StyleId = field.Name;

// here it should be fDate not sDate
fDate.PropertyChanged  = fDate_changed;