.NET MAUI Problem with ListView/CollectionView on iOS

This issue has been moved from a ticket on Developer Community.

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[severity:I’m unable to use this version] I have a program on the MAUI platform with the MVVM pattern. The problem occurs when running on an Iphone (any) of my program with ListView/CollectionView. When I click on the button or try to just fill in the ListView/Collection view, the program just freezes and nothing happens! I can’t write a program for iOS! (There is no difference between Release and Debug)

Example:

C#

using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Windows.Input;

namespace MauiApp1;

public partial class MainPage : ContentPage
{
    public MainPage()
    {
        InitializeComponent();
        BindingContext = new MainPageModel();
    }
}

public class MainPageModel : INotifyPropertyChanged
{

    public event PropertyChangedEventHandler? PropertyChanged;

    public ICommand ButtonCommand => new Command(UpdateList);

    private void UpdateList()
    {
        List list = new();
        for (int i = 0; i < 20; i++)
        {
            list.Add(new MainPageModel()
            {
                Example = "Text",
                Test = "Test"

            });
        }
        MyItems = new ObservableCollection(list);

    }

    public ObservableCollection MyItems
    {
        get => _MyItems;
        set
        {
            _MyItems = value;
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(MyItems)));
        }
    }
    private ObservableCollection _MyItems = new ObservableCollection();

    public string Example
    {
        get => _example;
        set
        {
            _example = value;
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(Example)));
        }
    }
    private string _example;

    public string Test
    {
        get => _test;
        set
        {
            _test = value;
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(Test)));
        }
    }
    private string _test;
}

XAML

<?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="MauiApp1.MainPage"
             xmlns:local="clr-namespace:MauiApp1"
             x:DataType="local:MainPageModel">
    <ScrollView Padding="6">
        <VerticalStackLayout>
            <Button Text="Add 20 items" Command="{Binding ButtonCommand}" />
            <ListView ItemsSource="{Binding MyItems}" HasUnevenRows="True">
                <ListView.ItemTemplate>
                    <DataTemplate x:DataType="local:MainPageModel">
                        <ViewCell>
                            <Grid>
                                <VerticalStackLayout>
                                    <VerticalStackLayout Margin="0,12,0,0">
                                        <Label Text="{Binding Example}"  />
                                        <Label Text="{Binding Example}"  />
                                        <Label Text="{Binding Example}"  />
                                        <Label Text="{Binding Example}"  />
                                    </VerticalStackLayout>
                                    <VerticalStackLayout Margin="0,12,0,0">
                                        <Label Text="{Binding Test}"  />
                                        <Label Text="{Binding Test}"  />
                                        <Label Text="{Binding Test}"  />
                                        <Label Text="{Binding Test}"  />
                                    </VerticalStackLayout>
                                </VerticalStackLayout>
                            </Grid>
                        </ViewCell>
                    </DataTemplate>
                </ListView.ItemTemplate>
            </ListView>
        </VerticalStackLayout>
    </ScrollView>
</ContentPage>

PS: I work on Windows 11 - Visual Studio and connect to a MacBook Pro - using the simulator to launch an Iphone

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Original Comments

Feedback Bot on 12/4/2022, 04:37 PM:

(private comment, text removed)

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Original Solutions

(no solutions)

[softlion]

I don’t have any performance issue after embedding CollectionView inside ContentView. It can scroll 10k items very fast.

But I agree that it requires a couple of trick that should be out of the box for everyone.

[jinxinjuan]

Verified this issue with Visual Studio Enterprise 17.8.0 Preview 1.0(.NET8). Not repro on iOS platforms with sample project (ListViewDemos). maui-samples/7.0/UserInterface/Views/ListViewDemos at main · dotnet/maui-samples (github.com)