April 2020 Deadline

Apple will no longer accept applications published with anything less than Xamarin.Forms 4.5 after April 2020.

This is due to the UIWebView flag that is in Xamarin.Forms 4.4 and earlier

ITMS-90809: Deprecated API Usage- Apple will stop accepting submissions of apps that use UIWebView APIs starting from April 2020 . 

Solution

Please visit this documentation for full explanation. Just to share the highlights, Telerik UI for Xamarin will need to:

• Xamarin.Forms 4.5 or higher – Pre-release versions of Xamarin.Forms 4.5 can be used.
• Xamarin.iOS 13.10.0.17 or higher – Check your Xamarin.iOS version in Visual Studio. This version of Xamarin.iOS is included with Visual Studio for Mac 8.4.1 and Visual Studio 16.4.3.
• Remove references to UIWebView – Your code should not have any references to UIWebView or any classes that make use of UIWebView.

Since 2020.1.218 the NuGet package for UWP Apps doesn't work, it references files that are not found during build.

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As soon the user tries to swipe more than one list item at the same time on iOS, the swiping functionality is not properly handled/

After setting the MajorLinesVisibility property to GridLineVisibility.Xy only the Y lines are showing up.

On UWP and Android the item can be swiped beyond the SwipeOffset property. Add option to restrict the swiped distance to the SwipeOffset value.

This can be reproduced in the SDK examples ->ListView -> Gestures -> CellSwipeEvents. 
1. Change the content of the items so that they have uneven height
2. Scroll down 
3. Delete an item by swiping
-> Expected result : The items re-arrange correctly
-> Actual result : The item is deleted but the ListView is scrolled up when the UI is updated

When LoadOnDemand event have loaded its data then there is some kind of jumping down through the new items while scrolling. 

If EndItemSwipe() is called inside the ItemSwiping event handler, the ItemSwiping event continues to occur on iOS until the user physically ends the swipe gesture.

I have a StackLayout, a ListView and within the listview a RadCheckBox and a Label. The StackLayout has a binding to IsVisible with the viewmodel. The ListView binds IsVisible to another property bound in the viewmodel. When OnAppearing of the Page, the ItemsSource of the ListView is set to an ObservableCollection. Now we get a crash on iOS and a Samsung Galayxy S with Android 9:

  at Telerik.XamarinForms.PrimitivesRenderer.iOS.TKCheckBox.CleanUI () [0x00007] in <04ee5ef79f6f4ed58266679a9a47ffaf>:0 
  at Telerik.XamarinForms.PrimitivesRenderer.iOS.CheckBoxRenderer.OnElementDetached (Telerik.XamarinForms.Primitives.RadCheckBox oldElement) [0x00025] in <04ee5ef79f6f4ed58266679a9a47ffaf>:0 
  at Telerik.XamarinForms.Common.iOS.IosRendererBase`2[S,T].Dispose (System.Boolean disposing) [0x0001f] in <b3d6af25b9654b5881f5a9721531628b>:0 
  at Foundation.NSObject.Dispose () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.4.0.2/src/Xamarin.iOS/Foundation/NSObject2.cs:147 
  at Xamarin.Forms.Platform.iOS.ListViewRenderer+UnevenListViewDataSource.CalculateHeightForCell (UIKit.UITableView tableView, Xamarin.Forms.Cell cell) [0x000aa] in D:\a\1\s\Xamarin.Forms.Platform.iOS\Renderers\ListViewRenderer.cs:897 
  at Xamarin.Forms.Platform.iOS.ListViewRenderer+UnevenListViewDataSource.GetEstimatedRowHeight (UIKit.UITableView table) [0x0008c] in D:\a\1\s\Xamarin.Forms.Platform.iOS\Renderers\ListViewRenderer.cs:812 
  at Xamarin.Forms.Platform.iOS.ListViewRenderer+UnevenListViewDataSource.UpdateEstimatedRowHeight (UIKit.UITableView tableView) [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.iOS\Renderers\ListViewRenderer.cs:823 
  at Xamarin.Forms.Platform.iOS.ListViewRenderer+ListViewDataSource.DetermineEstimatedRowHeight () [0x00009] in D:\a\1\s\Xamarin.Forms.Platform.iOS\Renderers\ListViewRenderer.cs:1271 
  at Xamarin.Forms.Platform.iOS.FormsUITableViewController.ViewWillLayoutSubviews () [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.iOS\Renderers\ListViewRenderer.cs:1599 
  at (wrapper managed-to-native) UIKit.UIApplication.UIApplicationMain(int,string[],intptr,intptr)
  at UIKit.UIApplication.Main (System.String[] args, System.IntPtr principal, System.IntPtr delegate) [0x00005] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.4.0.2/src/Xamarin.iOS/UIKit/UIApplication.cs:86 
  at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x0000e] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.4.0.2/src/Xamarin.iOS/UIKit/UIApplication.cs:65 
  at our app......


The remedy after a lot of trial and error was to replace the ListView with the Telerik ListView. Now the App no longer crashes. I hope this helps investigating the issue, since I noticed there are similar requests in the bug reports. 

I'm using: Xamarin Forms 4.2.0.848062, Telerik2019.3.1004.1.

Provide API which enables the group headers to remain in the view when scrolling until the next ones push them away.