Xamarin Forms Access parent collection item - xaml

Question

I have a problem. I have a CollectionView with a List<Album> albumList with inside an Album a List<Picture> Pictures. Now I created the following XAML:
<CollectionView ItemsSource="{Binding albumList}">
<CollectionView.ItemsLayout>
<GridItemsLayout Orientation="Vertical" />
</CollectionView.ItemsLayout>
<CollectionView.ItemTemplate>
<DataTemplate>
<Grid VerticalOptions="Center">
<Grid.RowDefinitions>
<RowDefinition Height="50"/>
<RowDefinition Height="90"/>
<RowDefinition Height="5"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="30"/>
<RowDefinition Height="10"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="3"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="3"/>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="3"/>
</Grid.ColumnDefinitions>
<StackLayout Grid.Row="3" Grid.Column="3" Grid.ColumnSpan="2" Padding="0" Margin="0"
BindableLayout.ItemsSource="{Binding Pictures}" Orientation="Vertical">
<BindableLayout.ItemTemplate>
<DataTemplate>
<StackLayout Orientation="Horizontal">
<Label Grid.Column="1" Text="{Binding albumList.Price, StringFormat='€ {0:F2}'}" TextColor="Black" FontSize="16" />
</StackLayout>
</DataTemplate>
</BindableLayout.ItemTemplate>
</StackLayout>
</Grid>
</DataTemplate>
</CollectionView.ItemTemplate>
</CollectionView>
Now I want to access the current Album.Price inside the following line: <Label Grid.Column="1" Text="{Binding albumList.Price, StringFormat='€ {0:F2}'}" TextColor="Black" FontSize="16" />
This is outside the current binding of Pictures, so how can I enter a value from outside the current Binding?

Answer 1

You can define the BindingContext from a reference of an element outside the nested Collection, give a name to your StackLayout for example:
<StackLayout x:Name="ElementForReference" Grid.Row="3" Grid.Column="3" Grid.ColumnSpan="2" Padding="0" Margin="0"
BindableLayout.ItemsSource="{Binding Pictures}" Orientation="Vertical">
And then define the BindingContext with the reference of the element outside the nested one:
{Binding BindingContext.Price, Source={x:Reference Name=ElementForReference}}