Is the scheduler changing my data-model ?

[Dan]

My actual example is quite complicated so I will not post the actual code here but I have encountered this behavior and I just want to know if this is intended :

-I have a scheduler data-bound to a collection of meetings (List<Meeting>)

-Each meeting in conceived like a viewmodel and has a public property Model that represents the Ef-Core database model

-Each Model has various properties describing the meeting among which is also a collection MeetingPersons (List<MeetingPerson>)

Here's what I noticed : 

-When the user uses the scheduler to edit an existing meeting, the MeetingPersons collection is emptied by syncfusion code. Actually what is happening is that using reflection the scheduler accesses the instance of my Meeting viewmodel class and switches the Model property instance with some other instance (I presume cached previously) that does not have any items in MeetingPersons.

Is this expected ? 

[Swathi Ravi]

Hi Dan,

Thanks for reaching out to us. It sounds like you're encountering unexpected behavior with the Syncfusion Scheduler, particularly with how data binding and model updates are being handled. To better understand and help you resolve this issue, could you kindly share the following details:

1. Are you using any custom templates, such as editorTemplate or eventTemplate in the Scheduler?
2. Can you provide code snippets related to how the Scheduler is bound to the List<Meeting> collection and any event handlers you've implemented (e.g., ActionBegin, ActionComplete, etc.)?
3. Please share the structure of the Meeting view model and the Model property, including how MeetingPersons is defined.

This information will help review your setup and identify whether any changes or optimizations are needed to maintain the integrity of your data model during edits.

Regards,

Swathi

[Dan]

Hi Swathi,

  Sorry for the late reply , I am trying to find the time to create a clean example, I will get back to you here asap.

Reg

[Ashokkumar Karuppasamy]

Hi Dan

Thanks for the update. We will wait to hear from you.

Regards,

Ashok

[Dan]

Hi, 

  I finally found the time to create a simple example, I attached the project here. If you put a brakepoint in 

SchedulerTestPageViewModel.ChangeAppointment and then try to change the meeting in the UI , you should see that the instance that comes in the method is different from the instance in InstructorMeetings collection which is the collection bound to the scheduler (use Make Object ID in VS to verify).

Also , if you look at the property OtherMeetings in the instance you will see that it has 0 elements while the one in the original has 1.

Best Regards,

Dan

PS: Just deleted the previous post , attached the wrong file 

Attachment: SchedulerTest_8e1345d1.zip

[Swathi Ravi]

Dan,

Thank you for sharing the issue replication sample with us.

After reviewing your sample, we noticed that you have used complex fields in the appointment data, which prevents the data from being processed correctly during editing. You can resolve this issue by handling it in the Scheduler's ActionCompleted event, as shown in the code snippet below:

<SfSchedule @ref="ScheduleRef" TValue=MeetingViewModel AllowInline="false" StartHour="09:00" EndHour="17:00" Height="100%" EnableAutoRowHeight="true">

    <ScheduleEventSettings TValue="MeetingViewModel" DataSource="vm.InstructorMeetings">

        <ScheduleField>

            <Field Name="OtherMeetings" />

        </ScheduleField>

    </ScheduleEventSettings>

    <ScheduleEvents TValue="MeetingViewModel"

    ActionCompleted="ActionCompleteHandler">

    </ScheduleEvents>

</SfSchedule>

@code {

    SfSchedule<MeetingViewModel> ScheduleRef;

    public async Task ActionCompleteHandler(ActionEventArgs<MeetingViewModel> args)

    {

        if (args.ActionType == ActionType.EventCreate)

        {

            //await vm.AddAppointment(args.AddedRecords[0]);

        }

        if (args.ActionType == ActionType.EventChange)

        {

            var data = vm.InstructorMeetings.Find(m => m.Id == args.ChangedRecords[0].Id);

            if (data != null)

            {

                // Add items from the original list

                foreach (var item in data.OtherMeetings)

                {

                    args.ChangedRecords[0].OtherMeetings.Add(item);

                }

            }

            await vm.ChangeAppointment(args.ChangedRecords[0]);

        }

        if (args.ActionType == ActionType.EventRemove)

        {

            //await vm.RemoveAppointment(args.DeletedRecords[0]);

        }

    }

}

Modified sample attached as a zip file.

Attachment: SchedulerTestModified_sample_c6a05f04.zip

[Dan]

Hi ,

  Yes, indeed this is how I have been handling it as well but it is not a good solution ... for one , it means I have to always be careful when I add reference type properties and pass their values back into the model (which basically the binding should do), but also when you look at a delete scenario ... the item in the viewmodel collection has already been deleted so ... there is no way to find it back at this point and I have to handle it in other ways as well ...

  But oh well , I just wanted to make sure this is an issue in the component and not in how I am using it, thanks!

Best Regards,

Dan

[Dan]

Actually thinking about it , for other people who may use the component, I think the best approach is to have a separate viewmodel collection that does not include any "complex properties" which is just used to bind to the scheduler and have your actual viewmodel objects representing the appointments in a separate Dictionary keyed by the appointment id. Then you would just be able to always find the correct viewmodel instance and also not worry about adding new properties or special handling of the delete scenario.