I am developing a .NET MAUI application using a Telerik RadDataGrid bound to a very large database via Entity Framework.

Because I am using the Load-On-Demand feature to fetch data incrementally as the user scrolls, the grid only holds a partial subset of the data in memory. Therefore, I cannot rely on the grid's built-in client-side filtering or sorting or search.

I need an architecture where:

Grid State to LINQ: Changes to the Grid's FilterDescriptors or SortDescriptors trigger a reset of the Auto-Load collection and invoke an Expression Builder. This builder must generate dynamic LINQ-to-Entities queries to sort and filter the data at the database level before it is paged back to the UI.

Cascading Distinct Values: Since the component doesn't have all the data, the 'Distinct Values' list for column filters must also be queried from the server. These lists need to be context-aware (cascading), showing only values relevant to the currently active filters of other columns.

Can you please help ?

Hi. During the scroll into view  (easy to repro with more or less large lists) the user can affect the RadCollectionView ItemsSource applying the search filter as DelegateFilterDescriptor and IFilter as a function. We would like to know the way how to synchronize both processes or cancel the scrolling.

Or would be good to make scroll into view as async.

ScrollItemIntoView(item, false)

The following crash happened:

System.IndexOutOfRangeException

Message: Arg_IndexOutOfRangeException
Telerik.Maui.Data.IndexStorage.ValueForIndex(Int32 index, Boolean approximate)
Telerik.Maui.Controls.RadCollectionView+<ScrollIndexIntoView>d__170.MoveNext()
System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task, ConfigureAwaitOptions options)
Telerik.Maui.Controls.RadCollectionView+<>c__DisplayClass168_0+<<ScrollIndexIntoViewCore>b__0>d.MoveNext()
System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
System.Threading.Tasks.Task+<>c.<ThrowAsync>b__128_0(Object state)
Android.App.SyncContext+<>c__DisplayClass2_0.<Post>b__0()
Java.Lang.Thread+RunnableImplementor.Run()
Java.Lang.IRunnableInvoker.n_Run(IntPtr jnienv, IntPtr native__this)
Android.Runtime.JNINativeWrapper.Wrap_JniMarshal_PP_V(_JniMarshal_PP_V callback, IntPtr jnienv, IntPtr klazz)

We are investigating functionality of MAUI controls before buying the kit and are stuck with the problem with RadChat/RadChatListView: we need to load more messages when user scrolled to top (or if it is already at the top), but there are no events/hooks that can be used to trigger page-loading method.

There are no events or attachable actions, and the only class ScrollMediator's members are fully consealed by internal directive and cannot be overriden/inherited/created either.

1. How to detect scroll position at the top/bottom?
2. How to initially scroll to certain message (aka unread one) instead of straight to bottom?

Please, help us in this matter or point out where it is discussed.

Hi everyone,

I'm running into an issue with the Telerik PDF Viewer in a .NET MAUI project.

Environment:

• Telerik.UI.for.Maui: 11.1.0

• .NET MAUI: 9.0.111

• .NET version: net9.0-ios

• Platform: iOS

Problem:
Scrolling inside the RadPdfViewer does not work on iOS. The same code works as expected on Android — I can scroll through the PDF content normally. On iOS, the viewer loads and displays the first page correctly, but it’s completely static: no vertical scroll or swipe works. However, navigation using PdfViewerNavigateToNextPageToolbarItem or PdfViewerNavigateToPreviousPageToolbarItem still functions as expected.

<ContentPage>
    <Grid RowDefinitions="Auto, *">
        <telerik:RadPdfViewerToolbar x:Name="pdfViewerToolbar"
                                     OverflowMode="Scroll"
                                     PdfViewer="{x:Reference pdfViewer}">
            <telerik:PdfViewerFitToWidthToolbarItem />
            <telerik:PdfViewerNavigateToPreviousPageToolbarItem />
            <telerik:PdfViewerNavigateToNextPageToolbarItem />
            <telerik:PdfViewerZoomInToolbarItem />
            <telerik:PdfViewerZoomOutToolbarItem />
            <telerik:PdfViewerSearchNavigationToolbarItem />
            <telerik:PdfViewerToggleLayoutModeToolbarItem />
        </telerik:RadPdfViewerToolbar>
        <telerik:RadPdfViewer x:Name="pdfViewer"
                              Grid.Row="1"
                              AutomationId="pdfViewer"
                              BackgroundColor="{StaticResource White}"
                              IgnoreSafeArea="False"
                              IsClippedToBounds="True"                              
                              LayoutMode="ContinuousScroll"
                              Source="{Binding PdfFile}" />
    </Grid>
</ContentPage>

Has anyone else encountered this issue, or is there a known workaround/fix for iOS?

Thanks in advance!

Jeff

When clicking the month dropdown and opening the month view,
there are those grey days (prev\next month days), clicking them sometimes shift the whole month to the new month (previous or next one) and sometimes it doesnt... maybe its about the line, im not completely sure whats the rule for this.

Its unclear.

Notice the 'arrows' are left aligned. How can I center these (I am working on a custom control based on NumericInput). I also want to center the numeric text.

Thanks.