[iOS] Shapes in CollectionView will cause item height increase

[NXDMN]

Description

When ItemTemplate of CollectionView contains BoxView (actually all Shapes type) that has WidthRequest and no HeightRequest, the height of items that appear after scrolling seem to follow previous items, like the previous item height is cached and used on items that come after, without remeasure them.

Steps to Reproduce

xaml file:

<?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.CollectionViewPage"
             Title="CollectionViewPage">
    <Grid Padding="10">
        <RefreshView Grid.Row="0" IsRefreshing="{Binding IsRefreshing}" Refreshing="RefreshView_Refreshing">
            <CollectionView ItemsSource="{Binding Items}" 
                            RemainingItemsThreshold="0"
                            RemainingItemsThresholdReached="CollectionView_RemainingItemsThresholdReached">
                <CollectionView.ItemTemplate>
                    <DataTemplate>
                        <VerticalStackLayout>
                            <Frame Margin="0,10" BackgroundColor="GhostWhite" Padding="0" CornerRadius="4">
                                <Grid
                                    ColumnSpacing="6"
                                    HorizontalOptions="FillAndExpand">
                                    <Grid.ColumnDefinitions>
                                        <ColumnDefinition Width="Auto" />
                                        <ColumnDefinition Width="*" />
                                    </Grid.ColumnDefinitions>

                                    <BoxView
                                        Grid.Column="0"
                                        Color="Red"
                                        VerticalOptions="FillAndExpand"
                                        WidthRequest="5" />
                                    <Label Grid.Column="1" Text="{Binding .}" FontSize="20"/>
                                </Grid>
                            </Frame>
                        </VerticalStackLayout>
                    </DataTemplate>
                </CollectionView.ItemTemplate>
            </CollectionView>
        </RefreshView>
    </Grid>
</ContentPage>

Code-behind file:

using System.Collections.ObjectModel;
using System.ComponentModel;

namespace MauiApp1;

public partial class CollectionViewPage : ContentPage
{
	public bool IsRefreshing { get; set; } = false;

	public ObservableCollection<string> Items { get; set;} = [];

	public CollectionViewPage()
	{
		InitializeComponent();
		BindingContext = this;
	}

        protected override void OnAppearing()
        {
                 base.OnAppearing();

		 LoadItems(true);
         }
 
	private void LoadItems(bool clearItems = false)
	{
		IsRefreshing = true;

		if(clearItems) Items.Clear();
		
		for(int i = 0; i <= 20; i++){
			Items.Add(GenerateRandomString());
		}

		IsRefreshing = false;
		OnPropertyChanged(nameof(IsRefreshing));
	}

        private readonly Random _random = new();

	private string GenerateRandomString()
	{
		const string chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 ";
		return new string(Enumerable.Repeat(chars, _random.Next(1, 256)).Select(s => s[_random.Next(s.Length)]).ToArray());
	}

	private void RefreshView_Refreshing(object sender, EventArgs eventArgs)
	{
		LoadItems(true);
	}

	private void CollectionView_RemainingItemsThresholdReached(object sender, EventArgs eventArgs)
	{
		LoadItems();
	}
}

Link to public reproduction project repository

No response

Version with bug

8.0.61 SR6.1

Is this a regression from previous behavior?

Yes, this used to work in Xamarin.Forms

Last version that worked well

Unknown/Other

Affected platforms

iOS

Affected platform versions

iOS 17.5

Did you find any workaround?

Use Grid

Relevant log output

No response

[github-actions]

Hi I'm an AI powered bot that finds similar issues based off the issue title.

Please view the issues below to see if they solve your problem, and if the issue describes your problem please consider closing this one and thumbs upping the other issue to help us prioritize it. Thank you!

Open similar issues:

• [iOS/Mac] CollectionView does not respect ItemSource DataTemplate height/width constraints (#17285), similarity score: 0.80
• [iOS] CollectionView item sizing wrong after refresh (#20443), similarity score: 0.79
• [iOS] CollectionView's height does not include measured height of Header and Footer to size of Content (#23435), similarity score: 0.79

Closed similar issues:

• iOS CollectionView items overlap when their content is resized (#21337), similarity score: 0.79
• [MAUI8] [iOS] Star Height of Grid.Row with CollectionView isn't correct (#18348), similarity score: 0.79

Note: You can give me feedback by thumbs upping or thumbs downing this comment.

[dotnet-policy-service]

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This issue will be closed automatically in 7 days if we do not hear back from you by then - please feel free to re-open it if you come back to this issue after that time.

[dotnet-policy-service]

This issue has been automatically marked as stale because it has been marked as requiring author feedback to reproduce the issue but has not had any activity for 4 days. It will be closed if no further activity occurs within 3 days of this comment. If it is closed, feel free to comment when you are able to provide the additional information and we will re-investigate.