Nested List view in Xamarin forms xaml with MVVM - xaml

Question

I want nested list view like below in xamarin forms
I am using XAML and wants to bind using MVVM
My model as below
public class LineItemTaxDto
{
public int InvoiceLineItemId { get; set; }
public int InvoiceId { get; set; }
public int TaxId { get; set; }
public decimal TaxRate { get; set; }
public decimal TaxAmount { get; set; }
public string TaxName { get; set; }
public ObservableCollection<LineItemTaxDto> SubTaxes { get; set; }
}
In this Group tax is my main taxname and it contains sub taxes (VAT, GST).
EDIT
My xaml code is below
<ListView x:Name="TaxListView" ItemsSource="{Binding Invoice.Taxgroup}" Grid.Row="2" Grid.Column="0" Grid.ColumnSpan="2" VerticalOptions="FillAndExpand" HorizontalOptions="FillAndExpand" SeparatorVisibility="None" HasUnevenRows="false" RowHeight="35">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<Grid RowSpacing="0" ColumnSpacing="0">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="150" />
</Grid.ColumnDefinitions>
<StackLayout Grid.Row="0" Grid.Column="0" Orientation="Horizontal" Spacing="0" HorizontalOptions="End">
<Label Text="{Binding Source={x:Reference TaxListView}, Path=BindingContext.CurrentOutlet.ReceiptTemplate.TaxLable, StringFormat='{0} ('}" FontSize="22" FontFamily="{x:Static resources:Fonts.ArialMTFont}" HorizontalOptions="End" Margin="0,5,0,5" />
<Label Text="{Binding TaxName, StringFormat='{0})'}" FontSize="22" FontFamily="{x:Static resources:Fonts.ArialMTFont}" HorizontalOptions="End" HorizontalTextAlignment="End" Margin="0,5,0,5" />
</StackLayout>
<Label Grid.Row="0" Grid.Column="1" Text="{Binding TaxAmount, Converter={Helpers:CurrencyAmountConverter}}" FontSize="22" FontFamily="{x:Static resources:Fonts.ArialMTFont}" HorizontalOptions="End" Margin="0,5,0,5" />
<ListView x:Name="TaxListView2" ItemsSource="{Binding Invoice.Taxgroup}" Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2" VerticalOptions="FillAndExpand" HorizontalOptions="FillAndExpand" SeparatorVisibility="None" HasUnevenRows="false" RowHeight="35">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<Grid RowSpacing="0" ColumnSpacing="0">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="150" />
</Grid.ColumnDefinitions>
<StackLayout Grid.Row="0" Grid.Column="0" Orientation="Horizontal" Spacing="0" HorizontalOptions="End">
<Label Text="{Binding TaxName}" FontSize="22" FontFamily="{x:Static resources:Fonts.ArialMTFont}" HorizontalOptions="End" HorizontalTextAlignment="End" Margin="0,5,0,5" />
</StackLayout>
<Label Grid.Row="0" Grid.Column="1" Text="{Binding TaxAmount, Converter={Helpers:CurrencyAmountConverter}}" FontSize="22" FontFamily="{x:Static resources:Fonts.ArialMTFont}" HorizontalOptions="End" Margin="0,5,0,5" />
</Grid>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</Grid>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
But is not working. please help me to what I am going wrong. Thanks in advance

Answer 1

Solved
I solve above result using single list no need to nested list view.
My code as below.
My xaml code look like:
<ListView
x:Name="TaxListView"
ItemsSource="{Binding Invoice.ReceiptTaxList}"
Grid.Row="2"
Grid.Column="0"
Grid.ColumnSpan="2"
VerticalOptions="FillAndExpand"
HorizontalOptions="FillAndExpand"
SeparatorVisibility="None"
HasUnevenRows="false"
RowHeight="35"
>
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<Grid RowSpacing="0" ColumnSpacing="0">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="150" />
</Grid.ColumnDefinitions>
<Label Grid.Row="0" Grid.Column="0" Text="{Binding TaxName}" FontSize="22" FontFamily="{x:Static resources:Fonts.ArialMTFont}" HorizontalOptions="End" HorizontalTextAlignment="End" Margin="0,5,0,5" />
<Label Grid.Row="0" Grid.Column="1" Text="{Binding TaxAmount, Converter={Helpers:CurrencyAmountConverter}}" FontSize="22" FontFamily="{x:Static resources:Fonts.ArialMTFont}" HorizontalOptions="End" Margin="0,5,0,5" />
</Grid>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
My view model code look like:
var TMPTaxList = invoice.InvoiceLineItems.Where(x => x.TaxId > 1).Select(x =>
{
return new KeyValuePair<LineItemTaxDto, ObservableCollection<LineItemTaxDto>>(new LineItemTaxDto()
{
InvoiceLineItemId = x.Id,
InvoiceId = x.InvoiceId,
TaxId = x.TaxId,
TaxRate = x.TaxRate,
TaxAmount = x.TaxAmount,
TaxName = "Tax (" + x.TaxName + ")"
}, x.LineItemTaxes);
});
var taxes = new ObservableCollection<LineItemTaxDto>();
foreach (var tax in TMPTaxList.GroupBy(tax => tax.Key.TaxId)
.Select(grp => grp.First()))
{
taxes.Add(tax.Key);
foreach (var subtax in tax.Value.Where(x => x.TaxId > 0))
{
taxes.Add(subtax);
}
}
invoice.ReceiptTaxList = taxes;