How to bind SelectedDateRange for mvvm

Question

Hello, I'd like to know if it is possible to bind SelectedDateRange for MCalendar

Indumathi Ravichandran · Accepted Answer

Hi Josh,Thank
you for providing the information. Upon reviewing the issue with the SelectedDateRange
not triggering without initialization in the ViewModel, we conducted through
testing across all platforms (Android, Windows, iOS, Mac) with latest version
24.2.4. After
commenting out the SelectedDateRange value initialization code, we observed
that the event triggered correctly as expected. We have also verified this
behavior with accompanying screenshots for your reference.In
order to further analyze and address the issue promptly, we kindly request the
following details:Reproduction of the issue in the attached sample.An issue replication video demonstrating the
observed behavior.Screenshot:Regards,Indumathi RAttachment: RangeCalendar_92869f69.zip

Indumathi Ravichandran · Answer

Hi Josh,Regarding Query: Hello, I'd like to know if it is possible to bind SelectedDateRange for MCalendarYes, you can bind the selected date range value from the ViewModel class. We have prepared the simple sample for achieving your requirement. Please find the sample from the attached link. Also please find the code and screenshot for the same.Code snippet:MainPage.Xaml ViewModel.CS public class CalendarViewModel { public CalendarDateRange SelectedDateRange { get; set; } public CalendarViewModel() { SelectedDateRange = new CalendarDateRange(new DateTime(2024, 2, 3, 9, 0, 0), new DateTime(2024, 2, 9, 9, 0, 0)); } } Screenshot: We hope that this helps you. Please let us know if you need further assistance.Regards,Indumathi R

Josh Pham · Answer

Thanks Indumathi for your reply. One thing I noticed is that when I selected start and end dates, it didn't trigger the binding to the SelectedDateRange in the viewmodel. Do you have any idea?

private CalendarDateRange selectedDateRange;

public CalendarDateRange SelectedDateRange

{

get

{

return selectedDateRange;

}

set

{

if (selectedDateRange != value)

{

selectedDateRange = value;

}

OnPropertyChanged(nameof(SelectedDateRange));

}

Indumathi Ravichandran · Answer

Hi Josh,Upon thorough investigation into the reported issue
concerning the event not firing for the End Date value, we have identified the
underlying cause within the calendar's implementation. It appears that a new
instance was only created for the start date of the selected range, while
neglecting to instantiate a new instance upon selection of the end date.
Consequently, this oversight resulted in the PropertyChanged event not being
triggered as expected.To rectify this issue and ensure proper notification for
changes to the end date property, we recommend wiring the PropertyChanged event
for the selectedDateRange object.
Below, I have provided a code snippet and sample demonstrating this approach:Code snippet:

public CalendarDateRange SelectedDateRange
  {
      get
      {
          return selectedDateRange;
      }
      set
      {
          selectedDateRange = value;
          selectedDateRange.PropertyChanged +=
  SelectedDateRange_PropertyChanged;
          NotifyPropertyChanged("SelectedDateRange");
      }
  }
   
  private void SelectedDateRange_PropertyChanged(object? sender,
  PropertyChangedEventArgs e)
  {
  ////  Todo your
  requirement here.
  }

Screenshot:

Implementing this adjustment should resolve the issue and
ensure that the PropertyChanged event is appropriately triggered for changes to
the end date property. Should you encounter any further challenges or require
additional assistance, please feel free to reach out.Regards,Indumathi RAttachment: RangeCalendar_b14df075.zip

Josh Pham · Answer

Indumathi, this implementation only works if the SelectedDateRange is initialized. If that value is not set, then the event is not triggered. Could you please help? Thank you.

Josh Pham · Answer

Thank you Indumathi. It works n

Indumathi Ravichandran · Answer

Hi Josh,Thank you for
the update. We hope issue has been resolved at your end. Please get back to us if you require further
other assistance from us.Regards,Indumathi R