ListView displays data only after it is played - xaml

Question

I'm having a hard time with XAML in Xamarin. Forms: The page is called and displayed without loading the data from the ListView (although the ListView is rendered because it changes the background color in its region).
Then, after I give a touch in the area of the ListView the data is presented i.e. initially the ListView shows nothing and after my touch on the screen it displays the data. However I have no event calling any refresh. I have already made sure of the code that the data is being received by it in a correct manner. Does anyone have any suggestions?
The following is the XAML code:
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="Coletas.Layouts.DetalheColeta">
<ContentPage.ToolbarItems>
<ToolbarItem Name="itemVisualizar" Order="Primary" Icon="pesquisar.png" Text="Visualizar" Priority="0" />
</ContentPage.ToolbarItems>
<ListView x:Name="Coleta" HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand" BackgroundColor="#FFCC80">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout Orientation="Vertical">
<Label Text="{Binding Coleta, StringFormat='Coleta {0:000000}'}" FontAttributes="Bold" FontSize="12"/>
<Label Text="{Binding Remetente}" FontAttributes="Bold" FontSize="12"/>
<Label Text="{Binding EnderecoRem}"/>
<Label Text="{Binding BairroRem}"/>
<Label Text="{Binding CidadeRem}"/>
<Label Text="{Binding ReferenciaRem}"/>
<Label Text="{Binding Destinatario}" FontAttributes="Bold" FontSize="12"/>
<Label Text="{Binding CidadeDes}"/>
<StackLayout Orientation="Horizontal" >
<Label Text="{Binding Peso, StringFormat='Peso: {0:0.00}'}"/>
<Label Text=" "/>
<Label Text="{Binding Quantidade, StringFormat='Volume: {0:0.00}'}"/>
</StackLayout>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</ContentPage>
The code that calls the DetalheColeta page is the below. This code is on another separate page:
private void GradeColetas_ItemSelected(object sender, SelectedItemChangedEventArgs e)
{
var item = e.SelectedItem as GridList;
if (item != null)
{
var id = item.Coleta;
Navigation.PushAsync(new DetalheColeta(id));
((ListView)sender).SelectedItem = null;
};
}
Any idea?

Answer 1

Discovered! The problem is in the constructor of the DetalheColeta page when using the Task. There is nothing wrong with the XAML and the previous page call. I executed the program in UWP and the message appeared: "The application called an interface that was marshalled for a different thread". I was testing in the Xamarin Live Player and did not give error. When correcting the call came to work.
Before:
public DetalheColeta (int collection)
{
InitializeComponent ()
Coleta_DetalheAsync (Collection)
}
Now:
public DetalheColeta (int collection)
{
InitializeComponent ()
Coleta_DetalheAsync (collection).Wait ();
}
Before:
Private async void Coleta_DetalheAsync (int collection)
{
Code
}
Now:
Private async Task Coleta_DetalheAsync (int collection)
{
Code
}