Control events inside interaction pop up not working - popup

Question

I have an interaction request pop up and inside that pop up, I have few controls like time picker, radcombobox and so on. I want change events of these controls hit in my view model class using prism commands.
my sample code is not working, time picket value change is not hitting on OnReasonTimeChanged Method.
XAML file
<i:Interaction.Triggers>
<i:EventTrigger SourceName=" " EventName="ValueChanged">
<i:InvokeCommandAction Command="{Binding ReasonTimeChanged}" />
</i:EventTrigger>
<prism:InteractionRequestTrigger SourceObject="{Binding SummaryConfirmationInteractionRequest}">
<prism:PopupChildWindowAction>
<prism:PopupChildWindowAction.ContentTemplate>
<DataTemplate>
<StackPanel Width="Auto" ScrollViewer.VerticalScrollBarVisibility="Hidden" Height="Auto"
MaxHeight="400" >
<ScrollViewer BorderThickness="1" VerticalScrollBarVisibility="Auto" Width="820" Height="Auto" MaxHeight="200">
<StackPanel Height="Auto" >
<controls:XRadGridView x:Name="UnitsGrid" ItemsSource="{Binding Units, Mode=OneWay}"
ScrollViewer.VerticalScrollBarVisibility="Auto"
MaxHeight="300"
IsReadOnly="True"
RowIndicatorVisibility="Collapsed"
CanUserInsertRows="False"
CanUserDeleteRows="False"
ShowColumnHeaders="False"
ShowGroupPanel="False"
CanUserResizeColumns="False"
CanUserReorderColumns="False"
AutoGenerateColumns="False">
<controls:XRadGridView.Columns>
<telerik:GridViewDataColumn Header="DUID"
DataMemberBinding="{Binding DisplayDuid}"
IsReadOnly="True"
Width="Auto" />
<telerik:GridViewDataColumn Header="ReasonTime">
<telerik:GridViewDataColumn.CellTemplate>
<DataTemplate>
<toolkit:TimePicker x:Name="ReasonTime"
VerticalAlignment="Center" HorizontalAlignment="Center" Width="20"
MaxWidth="20"
Loaded="ReasonTime_Loaded"
Format="HHmm"
Value="{Binding OfferHeader.ReasonTime, Mode=TwoWay}"
controls:TimePickerExtensions.UpdateBindingOnValueChanged="{Binding ApplyReasonToAll}"
TabIndex="0"/>
</DataTemplate>
</telerik:GridViewDataColumn.CellTemplate>
</telerik:GridViewDataColumn>
</controls:XRadGridView.Columns>
</controls:XRadGridView>
ViewModel code
Inside constructor I have below code
_reasonTimeChangedCommand = new DelegateCommand(OnReasonTimeChanged);
command details
private readonly DelegateCommand _reasonTimeChangedCommand;
public ICommand ReasonTimeChanged => _reasonTimeChangedCommand;
public void OnReasonTimeChanged()
{
}

Answer 1

The InvokeCommandAction should be inside the popup, to be used within the popup... but you bind to the value to a property (ReasonTime), and that property should be responsible for notifying the change. That's the view model's job, not just being a container for commands or forwarding properties from some DTO.