However, the following exception is thrown: "Can not set the content of androidWidget:RadioGroup as it doesn't have a ContentPropertyAttribute"
Not all native views can be used in xaml directly. RadioGroup is one of them.
To use it in your Xaml, you need to follow the below steps:
In YourProject.Droid create a custom RadioGroup control:
public class MyRadioGroup:RadioGroup
{
//Every native control in xaml will be wrapped in NativeViewWrapper, so we want to pass a NativeViewWrapper list here
IList<NativeViewWrapper> items;
public IList<NativeViewWrapper> ItemsSource
{
get {
items.Clear();
for (int i = 0; i < this.ChildCount; i++)
{
items.Add(new NativeViewWrapper(this.GetChildAt(i)));
}
return items;
}
set {
//xaml compiler will call this setter
if (items != value)
{
items = value;
this.RemoveAllViews();
foreach (NativeViewWrapper wrapper in items)
{
this.AddView(wrapper.NativeView);
}
}
}
}
public MyRadioGroup(Context context) : base(context)
{
items = new List<NativeViewWrapper>();
}
}
In your pcl library add necessary namespaces:
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
...
xmlns:androidWrapper="clr-namespace:Xamarin.Forms.Platform.Android;assembly=Xamarin.Forms.Platform.Android;targetPlatform=Android"
xmlns:androidWidget="clr-namespace:Android.Widget;assembly=Mono.Android;targetPlatform=Android"
xmlns:androidLocal="clr-namespace:NativeSwitch.Droid;assembly=NativeSwitch.Droid;targetPlatform=Android"
xmlns:formsAndroid="clr-namespace:Xamarin.Forms;assembly=Xamarin.Forms.Platform.Android;targetPlatform=Android"
xmlns:local="clr-namespace:NativeSwitch"
...">
Reference the custom MyRadioGroup in your xaml page:
<StackLayout Margin="20">
<androidLocal:MyRadioGroup x:Arguments="{x:Static formsAndroid:Forms.Context}" >
<androidLocal:MyRadioGroup.ItemsSource>
<x:Array Type="{x:Type androidWrapper:NativeViewWrapper}">
<androidWidget:RadioButton x:Arguments="{x:Static formsAndroid:Forms.Context}" Text="Scale1" />
<androidWidget:RadioButton x:Arguments="{x:Static formsAndroid:Forms.Context}" Text="Scale2" />
<androidWidget:RadioButton x:Arguments="{x:Static formsAndroid:Forms.Context}" Text="Scale3" />
<androidWidget:RadioButton x:Arguments="{x:Static formsAndroid:Forms.Context}" Text="Scale4" />
</x:Array>
</androidLocal:MyRadioGroup.ItemsSource>
</androidLocal:MyRadioGroup>
</StackLayout>
You can find a complete demo here.
For similar official tutorial, please refer to Subclassing Native Views
For passing arguments inside Xaml, please refer to Passing Arguments in Xaml
