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.net MAUI, android System.InvalidOperationException: 'Native View not set' on navigation

Can't find source of evil, have two pages, added as Singleton service, when i navigate to the second page for a first time everything great, when i navigate second time i get:
System.InvalidOperationException: 'Native View not set'
MAUI version 6.0.300-rc.2.5513+sha.8a017cf73-azdo.6048189
Emulator Android11 API 30
Tested on Desktop everything seems ok...
MauiProgram.cs
public static class MauiProgram
{
public static MauiApp CreateMauiApp()
{
var builder = MauiApp.CreateBuilder();
builder
.UseMauiApp<App>()
.ConfigureFonts(fonts =>
{
fonts.AddFont("OpenSans-Regular.ttf", "OpenSansRegular");
fonts.AddFont("OpenSans-Semibold.ttf", "OpenSansSemibold");
});
builder.Services.AddSingleton<ShellViewModel>();
builder.Services.AddSingleton<AppShell>();
builder.Services.AddSingleton<MainPage>();
builder.Services.AddSingleton<SettingsPage>();
return builder.Build();
}
}
App.xaml - default to new project
App.cs
public partial class App : Application
{
public App()
{
InitializeComponent();
MainPage = new AppShell();
Routing.RegisterRoute(nameof(MainPage), typeof(MainPage));
Routing.RegisterRoute(nameof(SettingsPage), typeof(SettingsPage));
}
}
AppShell.xaml
<?xml version="1.0" encoding="UTF-8" ?>
<Shell
x:Class="MauiAppTest.AppShell"
xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:local="clr-namespace:MauiAppTest"
xmlns:vm="clr-namespace:MauiAppTest.ViewModels"
x:DataType="vm:ShellViewModel"
Shell.FlyoutBehavior="Disabled">
<Shell.ToolbarItems>
<ToolbarItem Command="{Binding GoToSettings}" Text="Settings"/>
</Shell.ToolbarItems>
<ShellContent
Title="Hello, World!"
ContentTemplate="{DataTemplate local:MainPage}"
Route="MainPage" />
</Shell>
AppShell.cs
public partial class AppShell : Shell
{
public AppShell()
{
InitializeComponent();
BindingContext = new ShellViewModel();
}
}
ShellViewModel.cs
public class ShellViewModel: ObservableObject
{
public AsyncRelayCommand GoToSettings { get; private set; }
public ShellViewModel()
{
GoToSettings = new AsyncRelayCommand(async () => await Shell.Current.GoToAsync("SettingsPage"));
}
}
MainPage and SettingsPage just two default blank pages
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="MauiAppTest.MainPage"
Title="MainPage">
<StackLayout>
<Label Text="Welcome to .NET MAUI!"
VerticalOptions="Center"
HorizontalOptions="Center" />
</StackLayout>
</ContentPage>
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="MauiAppTest.SettingsPage"
Title="SettingsPage">
<StackLayout>
<Label Text="Welcome to .NET MAUI!"
VerticalOptions="Center"
HorizontalOptions="Center" />
</StackLayout>
</ContentPage>

Can not pass binding context through Navigation.pushasync with collectionview in xamarin

I am new to Xamarin and am making a small prototype application. Since this is a pilot project, I am keeping it simple and not using MVVM.
Expected output: I have a collection view and when I select an item from that view, I would like to bind the data from that Item, and navigate to a new page. I want the new page to be binded with the data I selected from the collection view as there will be a couple buttons on that page with different options.
Problem: When the item is selected from the collection view, I use Navigation.pushasync to open a new page. Inside of that routing action, I set the binding context to the data from the selected item. When I navigate to the page, none of the page is populated with data from the binding context I set in the previous page.
Comment: I had this working with a list view. But I wanted more flexibility in my styles for my list, so I am trying a collection view. I am having trouble trying to understand the way to bind data with a collection list vs a listview.
Main Page View:
MainPage.xaml:
<?xml version="1.0" encoding="UTF-8"?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="Notes.MainPage"
Title="My Numbers">
<ContentPage.ToolbarItems>
<ToolbarItem Text="+"
Clicked="OnNumberAddedClicked" />
<ToolbarItem Text="Q"
Clicked="GetCount"/>
<ToolbarItem Text="L"
Clicked="GetLast"/>
</ContentPage.ToolbarItems>
<ContentPage.Content>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<CollectionView x:Name="listView"
SelectionMode="Single"
ItemsSource="{Binding listView}">
<CollectionView.ItemTemplate>
<DataTemplate>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="100"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<StackLayout Orientation="Vertical"
Grid.Column="1">
<Label Text="{Binding MyNumber}" FontSize="Title"/>
<Label Text="{Binding DateAdded}" FontSize="Subtitle"/>
</StackLayout>
</Grid>
</DataTemplate>
</CollectionView.ItemTemplate>
</CollectionView>
</Grid>
</ContentPage.Content>
</ContentPage>
MainPage.xaml.cs:
using System;
using Xamarin.Forms;
using Notes.Models;
namespace Notes
{
public partial class MainPage : ContentPage
{
public MainPage()
{
InitializeComponent();
listView.SelectionChanged += ListView_SelectionChanged;
}
async void ListView_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
var num = e.CurrentSelection;
if (num != null)
{
await Navigation.PushAsync(new ActionsPage
{
BindingContext = num as NUM
});
}
}
protected override async void OnAppearing()
{
base.OnAppearing();
listView.ItemsSource = await App.Database.GetNumbersAsync();
}
}
}
Action Page View:
The circle is where the label is supposed to be, but the data won't bind.
ActionsPage.xaml:
<?xml version="1.0" encoding="UTF-8"?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="Notes.ActionsPage"
Title="NUM Actions">
<StackLayout>
<Label Text="{Binding myNumber}"
FontSize="Large"
VerticalOptions="CenterAndExpand"
HorizontalOptions="Center" />
<Button Text="Delete NUM"
VerticalOptions="CenterAndExpand"
HorizontalOptions="Center"
Clicked="OnDeleteButtonClicked" />
</StackLayout>
</ContentPage>
ActionsPage.xaml.cs:
using Notes.Models;
using System;
using Xamarin.Forms;
namespace Notes
{
public partial class ActionsPage : ContentPage
{
public ActionsPage()
{
InitializeComponent();
}
async void OnDeleteButtonClicked(object sender, EventArgs e)
{
var num = (NUM)BindingContext;
await App.Database.DeleteNumAsync(num);
await Navigation.PopAsync();
}
}
}
Any help is appreciated

The simple way to pass value on navigation is just to pass an argument in the constructor.
MainPage SelectionChanged event:
private async void ListView_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
var num = e.CurrentSelection[0] as NUM;
if (num != null)
{
await Navigation.PushAsync(new ActionsPage(num));
}
}
ActionPage:
public partial class ActionsPage : ContentPage
{
public int myNumber { get; set; }
public ActionsPage(NUM num)
{
InitializeComponent();
myNumber = num.MyNumber;
this.BindingContext = this;
}
async void OnDeleteButtonClicked(System.Object sender, System.EventArgs e)
{
//var num = (NUM)BindingContext;
//await App.Database.DeleteNumAsync(num);
//await Navigation.PopAsync();
}
}

Rg.Plugin.PopupPage error with the call line

I installed the plugin on the 3 projects (PCL/Android/IOS)
I am using Xamarin.forms and
The line that calls the popup page shows this error message after the app started:
Unhandled Exception:
System.InvalidOperationException: Platform is not created occurred
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class MenuView : ContentPage
{
List<Loja> lstLojas;
IGeolocator locator;
Loja lojaPerto;
Localizacao localizacao;
MyPopupPage s;
public MenuView()
{
s = new MyPopupPage();
InitializeComponent();
CallingGeolocatorAsync();
login();
}
void login()
{
Navigation.PushPopupAsync(s, true);
}
this is my PopUp Page.cs
using System;
using System.Threading.Tasks;
using Rg.Plugins.Popup.Pages;
using Rg.Plugins.Popup.Services;
using Xamarin.Forms;
namespace neoFly_Montana.PopUp
{
public partial class MyPopupPage : PopupPage
{
public MyPopupPage()
{
InitializeComponent();
}
private void OnClose(object sender, EventArgs e)
{
PopupNavigation.PopAsync();
}
protected override Task OnAppearingAnimationEnd()
{
return Content.FadeTo(0.5);
}
protected override Task OnDisappearingAnimationBegin()
{
return Content.FadeTo(1);
}
}
}
this is my popup xml
<?xml version="1.0" encoding="utf-8" ?>
<pages:PopupPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:pages="clr-namespace:Rg.Plugins.Popup.Pages;assembly=Rg.Plugins.Popup"
xmlns:animations="clr-namespace:Rg.Plugins.Popup.Animations;assembly=Rg.Plugins.Popup"
x:Class="neoFly_Montana.PopUp.MyPopupPage">
<!--Animations use example-->
<pages:PopupPage.Animation>
<animations:ScaleAnimation
PositionIn="Center"
PositionOut="Center"
ScaleIn="1.2"
ScaleOut="0.8"
DurationIn="400"
DurationOut="300"
EasingIn="SinOut"
EasingOut="SinIn"
HasBackgroundAnimation="True"/>
</pages:PopupPage.Animation>
<!-- Content -->
Can someone help?

You can't call that in a contructor...you need to use:
protected override void OnAppearing()
{
base.OnAppearing();
s = new MyPopupPage();
PopupNavigation.PushAsync(s, true);
}

Popuplogin.xaml:
<?xml version="1.0" encoding="UTF-8"?>
<pages:PopupPage
xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="SeralizationApp.Views.Popuplogin"
xmlns:animations="clr-namespace:Rg.Plugins.Popup.Animations;assembly=Rg.Plugins.Popup"
xmlns:pages="clr-namespace:Rg.Plugins.Popup.Pages;assembly=Rg.Plugins.Popup"
xmlns:myAnimations="clr-namespace:StalizationApp.Animations;assembly=MyProject">
<StackLayout Margin="12"
Padding="24"
Spacing="24"
BackgroundColor="White"
HorizontalOptions="Center"
VerticalOptions="Center">
<StackLayout>
<Label Text="Login" />
<Entry FontSize="30"
Text="Email" />
</StackLayout>
<StackLayout>
<Label Text="Contraseña"/>
<Entry FontSize="30"
IsPassword="True"
Text="Contraseña" />
</StackLayout>
//enter code here
<Button BackgroundColor="DodgerBlue"
FontSize="30"
Text="Login"
TextColor="White" />
</StackLayout>
</pages:PopupPage>
Popuplogin.cs
using Rg.Plugins.Popup.Pages;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
namespace SeralizationApp.Views
{
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class Popuplogin : PopupPage // ContentView
{
public Popuplogin ()
{
InitializeComponent ();
}
}
}

xamarin forms web view crashed

work with a web view however1 when I try to work with the web view
the page is crashed and get this error:
"An unhandled exception occured."
attaching my code:
also I want to know if I navagate with the web view to a Image
XAML:
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="MashamApp.MImageEditor">
<ContentPage.Content>
<StackLayout>
<StackLayout Orientation="Horizontal" Padding="10,10">
<Button Text="Back" HorizontalOptions="StartAndExpand" Clicked="backClicked" />
<Button Text="Forward" HorizontalOptions="End" Clicked="forwardClicked" />
</StackLayout>
<WebView x:Name="Browser" WidthRequest="1000" HeightRequest="1000" />
</StackLayout>
</ContentPage.Content>
</ContentPage>
C#:
using Syncfusion.SfImageEditor.XForms;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
namespace MashamApp
{
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class MImageEditor : ContentPage
{
public MImageEditor()
{
InitializeComponent();
Browser.Source = "http://www.walla.co.il";
}
private void backClicked(object sender, EventArgs e)
{
// Check to see if there is anywhere to go back to
if (Browser.CanGoBack) {
Browser.GoBack ();
} else { // If not, leave the view
Navigation.PopAsync ();
}
}
private void forwardClicked(object sender, EventArgs e)
{
if (Browser.CanGoForward) {
Browser.GoForward ();
}
}
}
}

Xamarin Forms changeing MapType with custom renderer isn't working

I took this sample project and added buttons in the xaml code
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:local="clr-namespace:CustomRenderer;assembly=CustomRenderer"
x:Class="CustomRenderer.MapPage">
<ContentPage.Content>
<StackLayout>
<StackLayout Orientation="Horizontal"
Spacing="10"
Padding="10"
HorizontalOptions="Center">
<Button x:Name="ButtonStreet" Text="Street" Clicked="OnStreetClicked"/>
<Button x:Name="ButtonHybrid" Text="Hybrid" Clicked="OnHybridClicked"/>
<Button x:Name="ButtonSatellite" Text="Satellite" Clicked="OnSatelliteClicked"/>
<Button x:Name="ButtonAddPin" Text="Add Pin" Clicked="OnAddPinClicked"/>
</StackLayout>
<local:CustomMap x:Name="customMap" MapType="Street" WidthRequest="{x:Static local:App.ScreenWidth}" HeightRequest="{x:Static local:App.ScreenHeight}" />
</StackLayout>
</ContentPage.Content>
And added the clicked event to the code behind
private void OnStreetClicked(object sender, EventArgs e)
{
customMap.MapType = MapType.Street;
}
private void OnHybridClicked(object sender, EventArgs e)
{
customMap.MapType = MapType.Hybrid;
}
private void OnSatelliteClicked(object sender, EventArgs e)
{
customMap.MapType = MapType.Satellite;
}
I noticed that the reason that it doesn't change is because of the OnMapReady method in the CustomMapRenderer class. Changeing to a Forms map solves the problem with updateing the MapType. But will probably give me other problems. What should I do?
public void OnMapReady (GoogleMap googleMap)
{
map = googleMap;
map.InfoWindowClick += OnInfoWindowClick;
map.SetInfoWindowAdapter (this);
}