Hello,

I'd been testing the trial version of the Telerik chart control for Xamarin in an Android app. Because it was working well, I'd purchased a license yesterday. And, I replaced the NuGet trial package with the license package. So far, so good.

However, now, when I try to build the project, it fails. (I've tried building both the Release and Debug version.)

The errors I see are below:

Severity Code Description Project File Line Suppression State
Error failed linking references. Ble.Client.Android
Error resource style/MainTheme.Base (aka com.companyname.ble.client:style/MainTheme.Base) not found. Ble.Client.Android
ErrorNU1301       Failed to retrieve information about 'Xamarin.AndroidX.AppCompat' from remote source 'https://packagesource/FindPackagesById()?id='Xamarin.AndroidX.AppCompat'&semVerLevel=2.0.0'. Ble.Client.Android D:\2023_devwork\BLE_Xamarin\XamarinBleCodeBehind-main\XamarinBleCodeBehind-main\Ble.Client\Ble.Client.Android\Ble.Client.Android.csproj 1

Any thoughts as to what might have broken, and, what I need to do in order to resolve the issue? (In case it helps, I'm including a screen capture of the Visual Studio 2022 output window.)

Thanks!

--Donn Morse

Please refer to this issue: https://feedback.telerik.com/xamarin/1509502-errors-with-latest-versions-of-androidx

Combobox, selection mode multiple.

Select the third item:

And you get this:

(also note the +1 circle going over the border)

However, set selected items programatically, and you get this:

There's plenty of space in the control.

Open the dropdown:

Still plenty of space, but... the button has disappeared.

Collapse it by clicking somewhere outside the control and you get back to the measurement bug:

I want to use a sticky header listview. 
I using the following code to render the sticky header list.

XML page code:

<?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="TEST.Views.AboutPage"
     xmlns:vm="clr-namespace:TEST.ViewModels"

     xmlns:telerikDataControls="clr-namespace:Telerik.XamarinForms.DataControls;assembly=Telerik.XamarinForms.DataControls"
     xmlns:telerikListView="clr-namespace:Telerik.XamarinForms.DataControls.ListView;assembly=Telerik.XamarinForms.DataControls"

     Title="{Binding Title}"
>

    <ContentPage.BindingContext>
        <vm:AboutViewModel />
    </ContentPage.BindingContext>

    <ContentPage.Resources>
        <ResourceDictionary>
            <Color x:Key="Accent">#96d1ff</Color>
        </ResourceDictionary>
        <DataTemplate x:Key="ListViewItemTemplate">
            <telerikListView:ListViewTemplateCell>
                <telerikListView:ListViewTemplateCell.View>
                    <Grid Padding="16, 0, 0, 0" BackgroundColor="#F1F2F5" HeightRequest="100">
                        <Label Text="{Binding Name}" TextColor="#6F6F70" FontSize="Small" />
                    </Grid>
                </telerikListView:ListViewTemplateCell.View>
            </telerikListView:ListViewTemplateCell>
        </DataTemplate>
        <DataTemplate x:Key="ListViewGroupHeaderTemplate">
            <Grid HeightRequest="40">
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="Auto" />
                    <ColumnDefinition />
                </Grid.ColumnDefinitions>                
                <Label Margin="0, 12, 0, 6" Text="{Binding }" Grid.Column="1" TextColor="DarkGray" FontSize="Medium" HorizontalOptions="Start" />
            </Grid>
        </DataTemplate>
        <telerikListView:ListViewGroupStyle x:Key="ListViewGroupHeaderStyle" BackgroundColor="White" />
    </ContentPage.Resources>

    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="*" />
        </Grid.RowDefinitions>       
            <telerikDataControls:RadListView
                x:Name="listView"
                ItemsSource="{Binding Cities}"
                ItemTemplate="{StaticResource ListViewItemTemplate}"
                GroupHeaderTemplate="{StaticResource ListViewGroupHeaderTemplate}"
                GroupHeaderStyle="{StaticResource ListViewGroupHeaderStyle}"
                IsGroupHeaderSticky="True"
                Grid.Row="0"
            >
                <telerikDataControls:RadListView.GroupDescriptors>
                    <telerikListView:PropertyGroupDescriptor PropertyName="Country"/>
                </telerikDataControls:RadListView.GroupDescriptors>

                <telerikDataControls:RadListView.LayoutDefinition>
                    <telerikListView:ListViewGridLayout HorizontalItemSpacing="5"
                                                        ItemLength="120"
                                                        SpanCount="2"
                                                        VerticalItemSpacing="5" />
                </telerikDataControls:RadListView.LayoutDefinition>
            </telerikDataControls:RadListView>
    </Grid>

</ContentPage>

ViewModels:

public class City
    {
        public string Name { get; set; }
        public string Country { get; set; }
    }

    public class ViewModel
    {
        public ObservableCollection<City> Cities { get; set; }

        public ViewModel()
        {
            this.Cities = new ObservableCollection<City>()
            {
                new City() { Name = "Barcelona", Country = "Spain"},
                new City() { Name = "Madrid", Country = "Spain"},
                new City() { Name = "Barcelona", Country = "Spain"},
                new City() { Name = "Madrid", Country = "Spain"},
                new City() { Name = "Rome", Country = "Italy"},
                new City() { Name = "Florence", Country = "Italy"},
                new City() { Name = "Florence", Country = "Italy"},
                new City() { Name = "London", Country = "England"},
                new City() { Name = "Manchester", Country = "England"},
                new City() { Name = "Manchester", Country = "England"},
                new City() { Name = "Manchester", Country = "England"},
                new City() { Name = "Manchester", Country = "England"},
                new City() { Name = "Manchester", Country = "England"},
                new City() { Name = "Manchester", Country = "England"},
                new City() { Name = "Manchester", Country = "England"},
                new City() { Name = "New York", Country = "USA"},
                new City() { Name = "New York", Country = "USA"},
                new City() { Name = "New York", Country = "USA"},
                new City() { Name = "New York", Country = "USA"},
                new City() { Name = "New York", Country = "USA"},
                new City() { Name = "New York", Country = "USA"},
                new City() { Name = "New York", Country = "USA"},
                new City() { Name = "Boston", Country = "USA"}
             };
        }
    }

Hi telerik team,

I know, my case is very specific, but I got this Bug and need to fix it somehow.

About: I have a RadSideDrawer in which I have a Collection View in which Header I have a Carousel View. When I rotate the phone in landscape mode the items are resized. After rotate back to portrait they are resized, but a lot of space appeare between them. So the layout is somekind wrong calculated. 
This only occure in this combination on iOS. If I remove the RadSideDrawer it works, if I remove the Collection View it also works, but both together not.

Reprosteps: Create a view with carousel embedded into the header of collection view embedded in to RadSideDrawer. (see attachment)
Rotate to landscape, rotate back to portrait mode.

System information:
iOS
xamarin: 5.0.0.2012
xamarin telerik ui: 2021.1.119.4

If you have a workarround for me, I will be very happy. Somehow to trigger a recalculation might help. I tryed set some InvalidateMeasure and ForceLayout but it didn't help. Either it don't work ot I apply it wrong. 
Any help is welcome!

Best regards,
Niko

Hi,

I had developed an Xamarin application, in a modal I open a PdfViewer.

PdfViewerPage pdfViewer = new PdfViewerPage(item.IdAllegato, item.Path, item.FlagScaricabile);

Navigation.PushModalAsync(pdfViewer);

I assign a url to the PdfViewer source.

pdfViewer.Source = new Uri(uri);

When I update Telerik.UI.for.Xamarin to v2021.1.119.1, I got following error:

Unable to resolve dependency 'Telerik.UI.for.Xamarin.Documents.Spreadsheet.FormatProviders.Xls'. Source(s) used: 'nuget.org', 'Telerik', 'Microsoft Visual Studio Offline Packages'.

Could you help to take a look? Thanks

Hi folks.

I am using the rad list view with grouping in my application. There are some cases when the list has empty groups (That's ok because according to the application's logic I can move items between groups). The problem is that the empty group it's not actually "Empty". It has a blank item which is not desirable behavior for me. I have a list view "item tapped" event which navigates the user to the details screen and when I tap on the empty group's item the application throws an exception because the list item is blank. I have attached a sample app according to this example and GIF files showing the issue.

Steps To Reproduce

1. Download the zip file
2. Open The app
3. Add necessary Telerik dlls (Can't send dlls with the sample because of size)
4. Tap on empty item

Versions

1. Xamarin Forms 5.0.0.1874
2. Telerik Controls 2020.3 (latest)
3. IDE Visual studio 2019

In Selection Changed method SelectedSeries is always empty.

Is there other way to get which series is selected?

Runtime exception: Java.Lang.RuntimeException: Font asset not found Fonts/telerikfont.ttf, when trying to access any page with controls that use telerikfont, like AutoCompleteView, TreeView, etc.

I have upgraded my Xamarin.Forms to version 4.5 and installed the dependent AndroidX nuget packages.  After upgrading UI for Xamarin to version 2020.1.318.1, I'm getting 3 errors below in my Xamarin Android project that seems to have to do with min SDK version when I try to build:

java/lang/String;Ljava/util/List;)[B :  invalid opcode ba - invokedynamic requires --min-sdk-version >= 26 (currently 13) 

com.android.dx.cf.code.SimException: ERROR in androidx.browser.customtabs.CustomTabsService$1.newSessionInternal:(Landroid/support/customtabs/ICustomTabsCallback;Landroid/app/PendingIntent;)Z: invalid opcode ba - invokedynamic requires --min-sdk-version >= 26 (currently 13)

com.android.dx.cf.code.SimException: ERROR in androidx.browser.trusted.ConnectionHolder.getServiceWrapper:()Lcom/google/common/util/concurrent/ListenableFuture;: invalid opcode ba - invokedynamic requires --min-sdk-version >= 26 (currently 13) 

I'm targeting Android 9 and set the minimum supported SDK to 26.  The error hasn't gone away.

I upgraded to latest Telerik to address a reference issue with AndroidX.RecyclerView but it seems that these new errors are showing up now. 

Is there something I can do to resolve the error or do I just have to wait for the next Telerik UI for Xamarin release?

If you have a project that has a dependency on: Xamarin.AndroidX.RecyclerView

It will cause a Release build failure due to Telerik.XamarinForms.DataControls using the wrong type in the renderer (AndroidX's RecyclerView instead of v7.Widgets's RecyclerView).

Here is the build error clarifying that it cannot find a `HasStableIds` property/method:

Error Mono.Linker.MarkException: Error processing method: 'System.Void Telerik.XamarinForms.DataControlsRenderer.Android.ItemsControlRenderer::OnElementAttached(Telerik.XamarinForms.DataControls.ItemsControl)' in assembly: 'Telerik.XamarinForms.DataControls.dll' ---> Mono.Cecil.ResolutionException: Failed to resolve System.Void AndroidX.RecyclerView.Widget.RecyclerView/Adapter::set_HasStableIds(System.Boolean)

Reproduce

You can use the attached project to reproduce the problem. Be sure to have the following settings:

• Build in Release configuration
• Set LinkerBehavior to SDK assemblies Only

Workaround

Uninstall Xamarin.AndroidX.RecyclerView

We have yet to upgrade our mobile app to Xamarin Forms 4.x and the latest Telerik releases due to a hard crash in Android when we leave a page containing a Telerik ListView control.   

The exception seems to mirror what is discussed here:  https://www.telerik.com/forums/null-ref-error-iorderedtraversalcontroller-updatetraversalorder

Here is what we are seeing... what is the latest on addressing this error?   We need to upgrade from Xamarin Forms 3.6.x soon.

10-16 15:00:06.082 I/MonoDroid( 4686): UNHANDLED EXCEPTION:

10-16 15:00:06.084 I/MonoDroid( 4686): System.NullReferenceException: Object reference not set to an instance of an object.

10-16 15:00:06.084 I/MonoDroid( 4686):   at Xamarin.Forms.Platform.Android.PageRenderer.Xamarin.Forms.Platform.Android.IOrderedTraversalController.UpdateTraversalOrder () [0x000a4] in D:\a\1\s\Xamarin.Forms.Platform.Android\Renderers\PageRenderer.cs:186

10-16 15:00:06.084 I/MonoDroid( 4686):   at Xamarin.Forms.Platform.Android.VisualElementRenderer`1[TElement].UpdateParentPageTraversalOrder () [0x00025] in D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:402

10-16 15:00:06.084 I/MonoDroid( 4686):   at Xamarin.Forms.Platform.Android.VisualElementRenderer`1[TElement].OnElementPropertyChanged (System.Object sender, System.ComponentModel.PropertyChangedEventArgs e) [0x00116] in D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:366

10-16 15:00:06.084 I/MonoDroid( 4686):   at (wrapper delegate-invoke) <Module>.invoke_void_object_PropertyChangedEventArgs(object,System.ComponentModel.PropertyChangedEventArgs)

10-16 15:00:06.084 I/MonoDroid( 4686):   at Xamarin.Forms.BindableObject.OnPropertyChanged (System.String propertyName) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:211

10-16 15:00:06.084 I/MonoDroid( 4686):   at Xamarin.Forms.Element.OnPropertyChanged (System.String propertyName) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\Element.cs:359

10-16 15:00:06.084 I/MonoDroid( 4686):   at Xamarin.Forms.Element.set_Parent (Xamarin.Forms.Element value) [0x000e9] in D:\a\1\s\Xamarin.Forms.Core\Element.cs:216

10-16 15:00:06.084 I/MonoDroid( 4686):   at Xamarin.Forms.Element.OnChildRemoved (Xamarin.Forms.Element child) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\Element.cs:341

10-16 15:00:06.084 I/MonoDroid( 4686):   at Xamarin.Forms.ViewCell.set_View (Xamarin.Forms.View value) [0x00019] in D:\a\1\s\Xamarin.Forms.Core\Cells\ViewCell.cs:25

10-16 15:00:06.084 I/MonoDroid( 4686):   at Telerik.XamarinForms.DataControlsRenderer.Android.ListView.CellContainerBase.Dispose (System.Boolean disposing) [0x00034] in <12ab8aad1d0a41af83f0de07840de122>:0

10-16 15:00:06.084 I/MonoDroid( 4686):   at Java.Lang.Object.Dispose () [0x00000] in <11a340ccc8de43f09c97400139266ef5>:0

10-16 15:00:06.084 I/MonoDroid( 4686):   at Telerik.XamarinForms.DataControlsRenderer.Android.FormsListViewDataSourceAdapterBase.ClearCachedViews () [0x00023] in <12ab8aad1d0a41af83f0de07840de122>:0

10-16 15:00:06.085 I/MonoDroid( 4686):   at Telerik.XamarinForms.DataControlsRenderer.Android.RadListViewDataSourceAdapter.ClearCachedViews () [0x00000] in <12ab8aad1d0a41af83f0de07840de122>:0

10-16 15:00:06.085 I/MonoDroid( 4686):   at Telerik.XamarinForms.DataControlsRenderer.Android.RadListViewDataSourceAdapter.Dispose (System.Boolean disposing) [0x00003] in <12ab8aad1d0a41af83f0de07840de122>:0

10-16 15:00:06.085 I/MonoDroid( 4686):   at Java.Lang.Object.Dispose () [0x00000] in <11a340ccc8de43f09c97400139266ef5>:0

10-16 15:00:06.085 I/MonoDroid( 4686):   at Telerik.XamarinForms.DataControlsRenderer.Android.ListViewRenderer.OnElementDetached (Telerik.XamarinForms.DataControls.RadListView oldElement) [0x00042] in <12ab8aad1d0a41af83f0de07840de122>:0

10-16 15:00:06.085 I/MonoDroid( 4686):   at Telerik.XamarinForms.Common.Android.AndroidRendererBase`2[S,T].Dispose (System.Boolean disposing) [0x0001f] in <14fbe24a55144e3caaf308ca594f4d5e>:0

10-16 15:00:06.085 I/MonoDroid( 4686):   at Java.Lang.Object.Dispose () [0x00000] in <11a340ccc8de43f09c97400139266ef5>:0

10-16 15:00:06.085 I/MonoDroid( 4686):   at Xamarin.Forms.Platform.Android.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x000c7] in D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:311

10-16 15:00:06.085 I/MonoDroid( 4686):   at Xamarin.Forms.Platform.Android.Platform+DefaultRenderer.Dispose (System.Boolean disposing) [0x0000a] in D:\a\1\s\Xamarin.Forms.Platform.Android\Platform.cs:1290

10-16 15:00:06.085 I/MonoDroid( 4686):   at Java.Lang.Object.Dispose () [0x00000] in <11a340ccc8de43f09c97400139266ef5>:0

10-16 15:00:06.085 I/MonoDroid( 4686):   at Xamarin.Forms.Platform.Android.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x000c7] in D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:311

10-16 15:00:06.085 I/MonoDroid( 4686):   at Xamarin.Forms.Platform.Android.Platform+DefaultRenderer.Dispose (System.Boolean disposing) [0x0000a] in D:\a\1\s\Xamarin.Forms.Platform.Android\Platform.cs:1290

10-16 15:00:06.085 I/MonoDroid( 4686):   at Java.Lang.Object.Dispose () [0x00000] in <11a340ccc8de43f09c97400139266ef5>:0

10-16 15:00:06.085 I/MonoDroid( 4686):   at Xamarin.Forms.Platform.Android.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x000c7] in D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:311

10-16 15:00:06.085 I/MonoDroid( 4686):   at Xamarin.Forms.Platform.Android.PageRenderer.Dispose (System.Boolean disposing) [0x00024] in D:\a\1\s\Xamarin.Forms.Platform.Android\Renderers\PageRenderer.cs:53

10-16 15:00:06.085 I/MonoDroid( 4686):   at Java.Lang.Object.Dispose () [0x00000] in <11a340ccc8de43f09c97400139266ef5>:0

10-16 15:00:06.085 I/MonoDroid( 4686):   at Xamarin.Forms.Platform.Android.AppCompat.FragmentContainer.OnDestroyView () [0x0003c] in D:\a\1\s\Xamarin.Forms.Platform.Android\AppCompat\FragmentContainer.cs:80

10-16 15:00:06.085 I/MonoDroid( 4686):   at Android.Support.V4.App.Fragment.n_OnDestroyView (System.IntPtr jnienv, System.IntPtr native__this) [0x00008] in <fefee6c2c695459088a9df092723e052>:0

10-16 15:00:06.085 I/MonoDroid( 4686):   at (wrapper dynamic-method) Android.Runtime.DynamicMethodNameCounter.97(intptr,intptr)

10-16 15:00:06.088 E/AppCenterCrashes( 4686): Unhandled Exception from source=AndroidEnvironment

10-16 15:00:06.088 E/AppCenterCrashes( 4686): System.NullReferenceException: Object reference not set to an instance of an object.

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Xamarin.Forms.Platform.Android.PageRenderer.Xamarin.Forms.Platform.Android.IOrderedTraversalController.UpdateTraversalOrder () [0x000a4] in D:\a\1\s\Xamarin.Forms.Platform.Android\Renderers\PageRenderer.cs:186

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Xamarin.Forms.Platform.Android.VisualElementRenderer`1[TElement].UpdateParentPageTraversalOrder () [0x00025] in D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:402

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Xamarin.Forms.Platform.Android.VisualElementRenderer`1[TElement].OnElementPropertyChanged (System.Object sender, System.ComponentModel.PropertyChangedEventArgs e) [0x00116] in D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:366

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at (wrapper delegate-invoke) <Module>.invoke_void_object_PropertyChangedEventArgs(object,System.ComponentModel.PropertyChangedEventArgs)

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Xamarin.Forms.BindableObject.OnPropertyChanged (System.String propertyName) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:211

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Xamarin.Forms.Element.OnPropertyChanged (System.String propertyName) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\Element.cs:359

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Xamarin.Forms.Element.set_Parent (Xamarin.Forms.Element value) [0x000e9] in D:\a\1\s\Xamarin.Forms.Core\Element.cs:216

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Xamarin.Forms.Element.OnChildRemoved (Xamarin.Forms.Element child) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\Element.cs:341

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Xamarin.Forms.ViewCell.set_View (Xamarin.Forms.View value) [0x00019] in D:\a\1\s\Xamarin.Forms.Core\Cells\ViewCell.cs:25

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Telerik.XamarinForms.DataControlsRenderer.Android.ListView.CellContainerBase.Dispose (System.Boolean disposing) [0x00034] in <12ab8aad1d0a41af83f0de07840de122>:0

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Java.Lang.Object.Dispose () [0x00000] in <11a340ccc8de43f09c97400139266ef5>:0

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Telerik.XamarinForms.DataControlsRenderer.Android.FormsListViewDataSourceAdapterBase.ClearCachedViews () [0x00023] in <12ab8aad1d0a41af83f0de07840de122>:0

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Telerik.XamarinForms.DataControlsRenderer.Android.RadListViewDataSourceAdapter.ClearCachedViews () [0x00000] in <12ab8aad1d0a41af83f0de07840de122>:0

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Telerik.XamarinForms.DataControlsRenderer.Android.RadListViewDataSourceAdapter.Dispose (System.Boolean disposing) [0x00003] in <12ab8aad1d0a41af83f0de07840de122>:0

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Java.Lang.Object.Dispose () [0x00000] in <11a340ccc8de43f09c97400139266ef5>:0

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Telerik.XamarinForms.DataControlsRenderer.Android.ListViewRenderer.OnElementDetached (Telerik.XamarinForms.DataControls.RadListView oldElement) [0x00042] in <12ab8aad1d0a41af83f0de07840de122>:0

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Telerik.XamarinForms.Common.Android.AndroidRendererBase`2[S,T].Dispose (System.Boolean disposing) [0x0001f] in <14fbe24a55144e3caaf308ca594f4d5e>:0

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Java.Lang.Object.Dispose () [0x00000] in <11a340ccc8de43f09c97400139266ef5>:0

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Xamarin.Forms.Platform.Android.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x000c7] in D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:311

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Xamarin.Forms.Platform.Android.Platform+DefaultRenderer.Dispose (System.Boolean disposing) [0x0000a] in D:\a\1\s\Xamarin.Forms.Platform.Android\Platform.cs:1290

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Java.Lang.Object.Dispose () [0x00000] in <11a340ccc8de43f09c97400139266ef5>:0

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Xamarin.Forms.Platform.Android.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x000c7] in D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:311

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Xamarin.Forms.Platform.Android.Platform+DefaultRenderer.Dispose (System.Boolean disposing) [0x0000a] in D:\a\1\s\Xamarin.Forms.Platform.Android\Platform.cs:1290

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Java.Lang.Object.Dispose () [0x00000] in <11a340ccc8de43f09c97400139266ef5>:0

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Xamarin.Forms.Platform.Android.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x000c7] in D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:311

10-16 15:00:06.088 E/AppCenterCrashes( 4686):   at Xamarin.Forms.Platform.Android.PageRenderer.Dispose (System.Boolean disposing) [0x00024] in D:\a\1\s\Xamarin.Forms.Platform.Android\

Hi Team,

I implemented radcheckbox in my xamarin telerik application. In which i select checkbox and afterword i post some data through webAPI. After completion of posting data i got response from server and my app got crashed and show me following stack trace data,

  at Telerik.XamarinForms.PrimitivesRenderer.iOS.CheckBoxRenderer.OnElementDetached (Telerik.XamarinForms.Primitives.RadCheckBox oldElement) [0x00025] in <f3723b4c1d3f406496717d69142c8f84>:0 

  at Telerik.XamarinForms.Common.iOS.IosRendererBase`2[S,T].Dispose (System.Boolean disposing) [0x0001f] in <81c15264f2164ef79a02e84ed79e8bfd>:0 

  at Foundation.NSObject.Dispose () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.14.0.114/src/Xamarin.iOS/Foundation/NSObject2.cs:147 

  at Xamarin.Forms.Platform.iOS.VisualElementPackager.Dispose (System.Boolean disposing) [0x0003f] in <612eab01c6f546df983c0637f996b4cd>:0 

  at Xamarin.Forms.Platform.iOS.VisualElementPackager.Dispose () [0x00000] in <612eab01c6f546df983c0637f996b4cd>:0 

  at Xamarin.Forms.Platform.iOS.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x00058] in <612eab01c6f546df983c0637f996b4cd>:0 

  at Foundation.NSObject.Dispose () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.14.0.114/src/Xamarin.iOS/Foundation/NSObject2.cs:147 

  at Xamarin.Forms.Platform.iOS.VisualElementPackager.OnChildRemoved (Xamarin.Forms.VisualElement view) [0x0003e] in <612eab01c6f546df983c0637f996b4cd>:0 

  at Xamarin.Forms.Platform.iOS.VisualElementPackager.OnChildRemoved (System.Object sender, Xamarin.Forms.ElementEventArgs e) [0x0000f] in <612eab01c6f546df983c0637f996b4cd>:0 

  at Xamarin.Forms.Element.OnChildRemoved (Xamarin.Forms.Element child) [0x00007] in D:\a\1\s\Xamarin.Forms.Core\Element.cs:343 

  at Xamarin.Forms.VisualElement.OnChildRemoved (Xamarin.Forms.Element child) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:750 

  at Xamarin.Forms.Layout`1[T].OnChildRemoved (Xamarin.Forms.Element child) [0x00000] in <4542de7f0f544d51b46d63bd15d5f6b5>:0 

  at Xamarin.Forms.Layout.OnInternalRemoved (Xamarin.Forms.View view) [0x00012] in D:\a\1\s\Xamarin.Forms.Core\Layout.cs:464 

  at Xamarin.Forms.Layout.InternalChildrenOnCollectionChanged (System.Object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e) [0x0002b] in D:\a\1\s\Xamarin.Forms.Core\Layout.cs:427 

  at (wrapper delegate-invoke) <Module>.invoke_void_object_NotifyCollectionChangedEventArgs(object,System.Collections.Specialized.NotifyCollectionChangedEventArgs)

  at System.Collections.ObjectModel.ObservableCollection`1[T].OnCollectionChanged (System.Collections.Specialized.NotifyCollectionChangedEventArgs e) [0x00018] in <a1ab7fc4639d4d84af41d68234158b1c>:0 

  at System.Collections.ObjectModel.ObservableCollection`1[T].OnCollectionChanged (System.Collections.Specialized.NotifyCollectionChangedAction action, System.Object item, System.Int32 index) [0x00009] in <a1ab7fc4639d4d84af41d68234158b1c>:0 

  at System.Collections.ObjectModel.ObservableCollection`1[T].RemoveItem (System.Int32 index) [0x00021] in <a1ab7fc4639d4d84af41d68234158b1c>:0 

  at System.Collections.ObjectModel.Collection`1[T].Remove (T item) [0x00027] in <939d99b14d934342858948926287beba>:0 

  at Xamarin.Forms.Layout.OnInternalAdded (Xamarin.Forms.View view) [0x0000b] in D:\a\1\s\Xamarin.Forms.Core\Layout.cs:451 

  at Xamarin.Forms.Layout.InternalChildrenOnCollectionChanged (System.Object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e) [0x00078] in D:\a\1\s\Xamarin.Forms.Core\Layout.cs:443 

  at (wrapper delegate-invoke) <Module>.invoke_void_object_NotifyCollectionChangedEventArgs(object,System.Collections.Specialized.NotifyCollectionChangedEventArgs)

  at System.Collections.ObjectModel.ObservableCollection`1[T].OnCollectionChanged (System.Collections.Specialized.NotifyCollectionChangedEventArgs e) [0x00018] in <a1ab7fc4639d4d84af41d68234158b1c>:0 

  at System.Collections.ObjectModel.ObservableCollection`1[T].OnCollectionChanged (System.Collections.Specialized.NotifyCollectionChangedAction action, System.Object item, System.Int32 index) [0x00009] in <a1ab7fc4639d4d84af41d68234158b1c>:0 

My xaml code,

<telerikControls:RadCheckBox IsChecked="{Binding IsSelected, Mode=TwoWay}" HorizontalOptions="Center" VerticalOptions="Center" />

My model class code,

private bool _isSelected;
        public bool IsSelected
        {
            get { return _isSelected; }
            set
            {
                _isSelected = value;
            }
        } 

Version information,

Xmarin form version : 4.1.0

Telerik UI version : 2019.2.802.1

iOS version 12.2

As the subject:

Before upgrading to the latest version of Telerik Controls, the Drag/Drop functionality worked correctly but after upgrading the list no longer updates and the item moved returns back to the original position.

Not using "ReorderEnded", everything works fine but this is needed to detect that something has been moved. 

Using Visual Studio for Mac, added packages using telerik nugget server, added radCalendar in xaml code. preview crashes and exception report window pops up.

I met an issue related to Xamarin.Forms RadListView (telerik component) which occurs only on iOS platform, while working fine on Android.
More details here - http://www.telerik.com/forums/radlistview-not-fitting-on-ios

The first time our system navigates to a page with a RadSideDrawer, the page loads as expected when we set: text values, drawer length etc.... in the code behind. However, when we navigate away from and navigate back to the page with the RadSideDrawer, it seems so only show was statically set in xaml. It does not show the dynamic values we set in the code behind even though those values seem to be set successfully.