Xamarin Forms: IMarkupExtension with bindable property does not work

Question

The binding is not working for the Image tag. When I debug, I see that the value of the Source in Extension class is always null? But the content of the label is not null.

Answer 1

Of course it does not !

It's not because you inherit from BindableObject that magically your object has a BindingContext set. And without a BindingContext, there's no way to resolve the {Binding Image}.

What you're looking for here is a Converter

class ImageSourceConverter : IValueConverter
{
    public object ConvertTo (object value, ...)
    {
        return ImageSource.FromResource(Source);
    }

    public object ConvertFrom (object value, ...)
    {
        throw new NotImplementedException ();
    }
}

You then add this converter to your Xaml root element resources (or Application.Resources and use it in your Bindings