MaterialCheckboxGroup NullReferenceException

[zillemarco]

🐛 Bug Report

MaterialCheckboxGroup throws a NullReferenceException when both SelectedIndices and Choices and bound to the respective binding properties and Choices is and empty list.

This is due to

XF-Material-Library/XF.Material/UI/Internals/BaseMaterialSelectionControlGroup.cs

Line 145 in 20bc606

case nameof(Choices) when Choices != null && Choices.Any():

and

XF-Material-Library/XF.Material/UI/MaterialCheckboxGroup.xaml.cs

Line 130 in 20bc606

foreach (var model in Models)

the foreach at MaterialCheckboxGroup.xaml.cs#L130 assumes Models to be valid, but due to BaseMaterialSelectionControlGroup.cs#L145 it's not.