How do I write xaml to bind (in MAUI) to a field other than the one specified in ItemsSource of the CollectionView? - xaml

Question

I have this (probably naïve question):
I have this xaml:
<CollectionView
ItemsSource="{Binding Receipts}"
SelectionMode="None">
<CollectionView.ItemTemplate>
<DataTemplate x:DataType="model:Receipt">
<Grid Padding="1, 1, 1, 1">
<Frame Style="{StaticResource CardView}">
<Frame.GestureRecognizers>
<TapGestureRecognizer
Command="{Binding Source={RelativeSource AncestorType={x:Type viewmodel:ER_Expense_Receipts_View_VM}}, Path=GoToReceiptDetailsCommand}"
CommandParameter="{Binding .}" />
</Frame.GestureRecognizers>
<Grid RowDefinitions="Auto, *" ColumnDefinitions="310, 20" RowSpacing="10">
<Image
x:Name="imgReceipt"
Aspect="AspectFit"
Margin="0"
Grid.ColumnSpan="2"
Source="{Binding ContentsThumbnail, Mode=OneWay, Converter={StaticResource ByteArrayToImageSourceConverter}}"
WidthRequest="300" />
<Label
Grid.Row="1"
FontSize="12"
HorizontalOptions="Center"
HorizontalTextAlignment="Center"
VerticalOptions="Start"
VerticalTextAlignment="Center"
HeightRequest="30"
Text="{Binding Description}">
</Label>
<ImageButton
x:Name="cmdDelete"
Command="{Binding Source={RelativeSource AncestorType={x:Type viewmodel:ER_Expense_Receipts_View_VM}}, Path=DeleteReceiptCommand}"
CommandParameter="{Binding ID}"
Grid.Row="1"
Grid.Column="1"
Source="delete2.svg"
HeightRequest="20"
WidthRequest="40">
<ImageButton.Triggers>
<DataTrigger TargetType="ImageButton" Binding="{Binding ExpenseReport.Status}" Value="{x:Static res:AppRes.StatusSent}">
<Setter Property="IsEnabled" Value="False" />
<Setter Property="TextColor" Value="Gray" />
</DataTrigger>
</ImageButton.Triggers>
</ImageButton>
</Grid>
</Frame>
</Grid>
</DataTemplate>
</CollectionView.ItemTemplate>
</CollectionView>
Receipts is a collection of Receipt objects in my "ER_Expense_Receipts_View_VM" model:
[ObservableProperty]
private Receipt receipt;
public ObservableCollection<Receipt> Receipts { get; } = new();
Also in my model I have this property
[ObservableProperty]
private Expense expense;
What I need to do here is to bind the "cmdDelete" ImageButton's property IsEnabled to the Status field of the ExpenseReport object in the model. See below. Alas, I get the message "Member not found in data context 'Receipt'".
So, please, what I am doing wrong here ? What's the correct syntax to bind that IsEnabled property to some field in the model other than from the Receipt objects ?
Thank you very much,
Alex