[iOS] Xamarin forms list view unnecessarily scrolling to top when load more command is executed[Bug]

[SatyaRamprasad]

Description

[iOS] Xamarin forms list view unnecessarily scrolling to top when load more command is executed

Steps to Reproduce

1. Create a custom list view with LoadMoreCommand
   public class CustomListView : ListView
   {

    public static readonly BindableProperty LoadMoreCommandProperty =
        BindableProperty.Create("LoadMoreCommand", typeof(ICommand), typeof(CustomListView), default(ICommand));
   
    public ICommand LoadMoreCommand
    {
        get { return (ICommand)GetValue(LoadMoreCommandProperty); }
        set { SetValue(LoadMoreCommandProperty, value); }
    }
   
    public CustomListView()
    {
        ItemAppearing += InfiniteListView_ItemAppearing;
    }
   
    void InfiniteListView_ItemAppearing(object sender, ItemVisibilityEventArgs e)
    {
        var items = ItemsSource as IList;
   
        if (items != null && e.Item == items[items.Count - 1])
        {
            if (LoadMoreCommand != null && LoadMoreCommand.CanExecute(null))
                LoadMoreCommand.Execute(null);
        }
    }
   

   }

2. Add items to customlistview

3. Run and scroll to last item

Expected Behavior

Should not scroll to top after load more command

Actual Behavior

Scrolling to top when load more command executed

Basic Information

• Version with issue: 4.3.0.908675
• Last known good version:
• IDE: Visual Studio 2019 Community 16.3.5
• Platform Target Frameworks:
  • iOS: 13.1
• Nuget Packages: Xamarin Forms 4.3.0.908675
• Affected Devices:

Screenshots

Reproduction Link

[adrianknight89]

@SatyaRamprasad I'm not sure what kind of priority ListView has now, but my suggestion would be that you switch to CollectionView if at all possible. You're likely to face other types of issues with ListView in the future that won't get addressed soon.

[hartez]

@SatyaRamprasad Can you post the code for the command you are executing? What exactly does "load more" do?

[SatyaRamprasad]

@hartez i have added a sample project which reproduces the issue while scrolling.
Load more command calls load data function which adds new items to list
ListViewScrolling.zip

[LeoJHarris]

@hartez I had the same issue as described in the title, I had a function to load more messages to a chat listview that was bound to an ObservableRangeCollection, on load more it would simply bulk insert new messages which was causing scrolling to automatically scrolll to top of listview on iOS. Android it worked fine and did not auto scroll but on iOS it wants to auto scroll to top of listview. I have not yet tried with Collection view.

[lucas-zimerman]

is there any workaround for this issue? it's impacting alot my app

[BalsamIbrahim]

I'm have the same problem :( :(

[SatyaRamprasad]

@BalsamIbrahim As this list view issue didn't fixed yet, i switched my list to collection view. No issues now

[SatyaRamprasad]

is there any workaround for this issue? it's impacting alot my app

Try using Collection View

[MereDoku]

if we use CollectionView in a RefreshView then there is exactly the same problem:
#10640
So actually use CollectionView is not the solution.
it's unacceptable that this bug is not fixed after so much time.
It makes us look bad to our customers.

[pboisso]

Have this problem also.

[rozek1szymon]

same here

[marthinch]

I have tricky solution to prevent this issue by removing IsRefreshing flag in your list view.

[Elashi]

I have tricky solution to prevent this issue by removing IsRefreshing flag in your list view.

Can you share it please

[jrlawhorne]

Same issue. What I've done that seems to prevent the jump is to disable IsRefreshing and pull to refresh. Of course, there may be other yet to be discovered consequences to making those changes...