Xamarin CollectionView - Accessing Parent bindings in ItemTemplate? - xaml

Question

I have the below XAML which contains a CollectionView header and associated CollectionView items. The source of the data (ItemsSource) is a list called 'users' (also shown below).
Is there anyway for me to access the properties in the top level (i.e the ones the headers are using) ?
Thanks !
<CollectionView Grid.Row="1" x:Name="users" IsGrouped="True" SelectionMode="Single">
<CollectionView.GroupHeaderTemplate>
<DataTemplate>
<StackLayout Orientation="Horizontal" MinimumHeightRequest="200" BackgroundColor="{Binding tint_colour}">
<Image Source="{Binding school_image}" WidthRequest="120" HeightRequest="100"/>
<Label Text="{Binding organisation_title}"
TextColor="{Binding font_colour}"
FontSize="Large"
FontAttributes="Bold"
VerticalTextAlignment="Center"></Label>
<StackLayout.GestureRecognizers>
<TapGestureRecognizer NumberOfTapsRequired="1" Tapped="HeaderTapped" CommandParameter="{Binding organisation_title}"></TapGestureRecognizer>
</StackLayout.GestureRecognizers>
</StackLayout>
</DataTemplate>
</CollectionView.GroupHeaderTemplate>
<CollectionView.ItemsLayout>
<LinearItemsLayout Orientation="Vertical" ItemSpacing="1"/>
</CollectionView.ItemsLayout>
<CollectionView.ItemTemplate>
<DataTemplate>
<StackLayout HeightRequest="200">
<Grid IsVisible="true" VerticalOptions="FillAndExpand" HorizontalOptions="FillAndExpand">
<behaviors:Expander x:Name="MainExpander" CollapseAnimationLength="500" IsExpanded="false" >
<behaviors:Expander.Header>
<Grid HorizontalOptions="FillAndExpand">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="100"/>
<ColumnDefinition Width="10"/>
</Grid.ColumnDefinitions>
<Frame HeightRequest="40" WidthRequest="40" CornerRadius="20" HorizontalOptions="Start" VerticalOptions="Center" Margin="20" Padding="0" BackgroundColor="Maroon">
<Label Text="{Binding student_initial}" TextColor="White" HorizontalOptions="Center" VerticalOptions="Center" HorizontalTextAlignment="Center" VerticalTextAlignment="Center" />
</Frame>
<StackLayout Grid.Column="2" HorizontalOptions="StartAndExpand" VerticalOptions="Center" Margin="20">
<Label x:Name="StudentName" Text="{Binding student_fullname}"></Label>
<Label x:Name="StudentID" IsVisible="false" Text="{Binding school_image}"></Label>
</StackLayout>
</Grid>
</behaviors:Expander.Header>
<Grid RowSpacing="0" HorizontalOptions="FillAndExpand" HeightRequest="240" VerticalOptions="FillAndExpand">
<Grid.RowDefinitions>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Button Grid.Row="0" Text="Messages" Clicked="Button_Clicked"></Button>
<Button x:Name="btnTopUp" Grid.Row="1" Text="Quick Topup" Clicked="Button_Clicked" IsVisible="{Binding topup_product_id, Converter={StaticResource IsNotNullOrEmptyConverter}}"></Button>
<Button Grid.Row="2" Text="Payments" Clicked="Button_Clicked"></Button>
</Grid>
<!--TODO: Look at adding a balance for childrens topups?-->
</behaviors:Expander>
</Grid>
</StackLayout>
</DataTemplate>
</CollectionView.ItemTemplate>
</CollectionView>
This is my user ItemsSource, which is a List of AccountGroup items :
public class Account : INotifyPropertyChanged
{
public string student_unique_id { get; set; }
public string student_fullname { get; set; }
public string organisation_id { get; set; }
public string organisation_title { get; set; }
public string student_token { get;set;}
public string reg_branding_url { get;set;}
public string tint_colour { get;set;}
public string font_colour { get;set;}
public string topup_product_id { get;set;}
private string _height;
public string height
{
set { SetProperty(ref _height, value); }
get { return _height; }
}
private bool _isVisible;
public bool isVisible
{
set { SetProperty(ref _isVisible, value); }
get { return _isVisible; }
}
public string student_initial
{
get
{
return student_fullname[0].ToString();
}
}
public string school_image
{
get
{
return $"{Constants.apiBaseUrl}store/images/uploaded/mobile/{reg_branding_url}";
}
}
bool SetProperty<T>(ref T storage, T value, [CallerMemberName] string propertyName = null)
{
if (Object.Equals(storage, value))
return false;
storage = value;
OnPropertyChanged(propertyName);
return true;
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
public class AccountGroup : List<Account>, INotifyPropertyChanged
{
public string organisation_title { get; set; }
public string school_image { get; set; }
public string tint_colour { get; set; }
public string font_colour { get; set; }
public List<Account> accountList { get; set; }
private bool _isVisible;
public bool isVisible
{
set { SetProperty(ref _isVisible, value); }
get { return _isVisible; }
}
bool SetProperty<T>(ref T storage, T value, [CallerMemberName] string propertyName = null)
{
if (Object.Equals(storage, value))
return false;
storage = value;
OnPropertyChanged(propertyName);
return true;
}
public AccountGroup(string orgTitle, string orgImage, string orgTint, string orgFont, List<Account> accounts) : base(accounts)
{
organisation_title = orgTitle;
school_image = orgImage;
tint_colour = orgTint;
font_colour = orgFont;
accountList = accounts;
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}