[Bug] Xamarin.Forms.Platform.iOS.EntryRendererBase`1[TControl].GetClearButtonTintImage crash

[AndreasReitberger]

Description

Using iOS 13 on an iPhone 8 simulator leads to following crash while using entry box with ClearButtonVisibility to set "WhileEditing".

<Entry 
      Grid.Column="1"
      Placeholder="{x:Static localization:Strings.SettingsPrintServerConnectionAddress}"
      Text="{Binding ServerAddress, Mode=TwoWay}" 
      Style="{StaticResource DefaultBorderlessEntry}"
      ClearButtonVisibility="WhileEditing"
      Margin="16,2,16,4"
      />

Newer iOS versions are working fine.

Steps to Reproduce

1. Setup an iPhone 8 simulator running iOS 13.1
2. Insert the xaml code above
3. See the exception

Expected Behavior

No exception.

Actual Behavior

Exception gets thrown.
exc {System.NullReferenceException: Object reference not set to an instance of an object at Xamarin.Forms.Platform.iOS.EntryRendererBase1[TControl].GetClearButtonTintImage (UIKit.UIImage image, UIKit.UIColor color) [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.iO…}
`

Basic Information

• Version with issue: SR4
• Platform Target Frameworks:
  • iOS: iOS 13.1 on iPhone 8 (Simulator and real device)
• Affected Devices: iPhone 8 (Simulator / real device)

Stacktrace

Xamarin.Forms.Platform.iOS.EntryRendererBase1[TControl].GetClearButtonTintImage (UIKit.UIImage image, UIKit.UIColor color) [0x00000] in D:\\a\\1\\s\\Xamarin.Forms.Platform.iOS\\Renderers\\EntryRenderer.cs:591 \n at Xamarin.Forms.Platform.iOS.EntryRendererBase…"

Workaround

[AndreasReitberger]

Seems to be related to: #14479

[jfversluis]

Fixed with #14479