DatePicker set InitialViewDate for EndDate based on StartDate

Radzen.Blazor Components
1

I have a simple form with a label and two date pickers where the user is supposed to pick a StartDate and a EndDate. If the user selects e.g. 6/1/2040 the EndDate DatePicker should start at this given time. I have made the following:

HTML:
  <RadzenLabel Text=@local[ResourcesKeys.Keys.StartDate] class="col-sm-3 col-form-label" />
  <div class="col inputSpacer">
      <RadzenDatePicker Disabled="@IsCurrent"
                        @bind-Value="ResourcePlanFormObject.StartDate"
                        Min="DateTime.Now"
                        style="width: 100%;"
                        ShowTime="true"
                        HoursStep="1"
                        MinutesStep="5"
                        TValue="DateTimeOffset?"
                        Kind="DateTimeKind.Local"
                        DateFormat="yyyy-MM-dd:hh-mm"
                        AllowInput="false" />
      <ValidationMessage For="@(() => ResourcePlanFormObject.StartDate)" />
  </div>

  <RadzenLabel Text=@local[ResourcesKeys.Keys.EndDate] class="col-sm-3 col-form-label" />
  <div class="col inputSpacer">
      <RadzenDatePicker @bind-Value="ResourcePlanFormObject.EndDate"
                        style="width: 100%;"
                        ShowTime="true"
                        HoursStep="1"
                        MinutesStep="5"
                        TValue="DateTimeOffset?"
                        Kind="DateTimeKind.Local"
                        InitialViewDate="SetEndDateMinAndInitialView()"
                        Min="SetEndDateMinAndInitialView()"
                        DateFormat="yyyy-MM-dd-hh-mm"
                        AllowInput="false"
                        Change="@(() => EditContext.Validate())" />
      <ValidationMessage For="@(() => ResourcePlanFormObject.EndDate)" />
  </div>

C# code behind:
  private DateTime? SetEndDateMinAndInitialView()
  {
      if (ResourcePlanFormObject.StartDate == null)
      {
          return DateTime.Now;
      }
      else
      {
          return ResourcePlanFormObject.StartDate.Value.DateTime;
      }
  }

I would assume this code should do exactly what I want but the initial date doesn't change. But if I hardcode e.g. DateTime.Now.AddMonths(5) and set it within my InitialViewDate the DatePicker displays the right start month

2

By looking into the implementation of DatePicker in the GitHub repo I found a way to make what I want possible. First I set a ref to the EndDate DatePicker in the code behind and added a Change action on the StartDate DatePicker and added an internal method class which updates the Value property on the EndDateDatePicker.

HTML:
<RadzenLabel Text=@local[ResourcesKeys.Keys.StartDate] class="col-sm-3 col-form-label" />
<div class="col inputSpacer">
    <RadzenDatePicker Disabled="@IsCurrent"
                      @bind-Value="ResourcePlanFormObject.StartDate"
                      Min="@MIN_DATEPICKER_VALUE"
                      style="width: 100%;"
                      ShowTime="true"
                      HoursStep="1"
                      MinutesStep="5"
                      TValue="DateTimeOffset?"
                      Kind="DateTimeKind.Local"
                      DateFormat="@DATE_FORMAT"
                      AllowInput="false" 
                      Change="@(() => UpdateInitialViewDateForEndDateDatePicker())"/>
    <ValidationMessage For="@(() => ResourcePlanFormObject.StartDate)" />
</div>

<RadzenLabel Text=@local[ResourcesKeys.Keys.EndDate] class="col-sm-3 col-form-label" />
<div class="col inputSpacer">
    <RadzenDatePicker @bind-Value="ResourcePlanFormObject.EndDate"
                      style="width: 100%;"
                      ShowTime="true"
                      HoursStep="1"
                      MinutesStep="5"
                      TValue="DateTimeOffset?"
                      Kind="DateTimeKind.Local"
                      InitialViewDate="@SetEndDateMinAndInitialView()"
                      Min="@SetEndDateMinAndInitialView()"
                      DateFormat="@DATE_FORMAT"
                      AllowInput="false"
                      Change="@(() => EditContext.Validate())"
                      @ref="EndDateDatePicker"/>
    <ValidationMessage For="@(() => ResourcePlanFormObject.EndDate)" />
</div>

C# code behind:
private RadzenDatePicker<DateTimeOffset?> EndDateDatePicker;

private void UpdateInitialViewDateForEndDateDatePicker()
{
    if (ResourcePlanFormObject.StartDate >= ResourcePlanFormObject.EndDate) // This if-condition is needed if the user selects a StartDate thats greater than the EndDate to keep updating the InitialViewDate correctly
    {
        ResourcePlanFormObject.EndDate = null;
    }
    EndDateDatePicker.Value = DateTimeOffset.Now;
}

This is without a doubt a doubt a hack about the intended use of the component but it gets the job done