MvxNetworkActivityIndicatorTargetBinding for mvvmcross iOS

MvxNetworkActivityIndicatorTargetBinding.cs

    public abstract class MvxTargetBinding2 : MvxBinding, IMvxTargetBinding
    {
        private readonly object _target;

        protected MvxTargetBinding2(object target)
        {
            _target = target;
        }

        protected object Target
        {
            get { return _target; }
        }

        public virtual void SubscribeToEvents()
        {
            // do nothing by default
        }

        protected virtual void FireValueChanged(object newValue)
        {
            var handler = ValueChanged;

            if (handler != null)
                handler(this, new MvxTargetChangedEventArgs(newValue));
        }

        public abstract Type TargetType { get; }
        public abstract void SetValue(object value);

        public event EventHandler<MvxTargetChangedEventArgs> ValueChanged;
        public abstract MvxBindingMode DefaultMode { get; }
    }

    public class MvxNetworkActivityIndicatorTargetBinding : MvxTargetBinding2
    {
        public override MvxBindingMode DefaultMode
        {
            get { return MvxBindingMode.OneWay; }
        }

        public static void Register(IMvxTargetBindingFactoryRegistry registry)
        {
            registry.RegisterFactory(new MvxCustomBindingFactory<UIView>("NetworkActivityIndicator", source => new MvxNetworkActivityIndicatorTargetBinding(source)));
        }

        public MvxNetworkActivityIndicatorTargetBinding(UIView source) : base(source)
        {
        }

        public override Type TargetType
        {
            get { return typeof(bool); }
        }

        public override void SetValue(object value)
        {
            if (!(value is bool))
                return;

            UIApplication.SharedApplication.NetworkActivityIndicatorVisible = (bool)value;
        }
    }

Register

//In mvvmcross setup.cs

        protected override void FillTargetFactories(IMvxTargetBindingFactoryRegistry registry)
        {
            base.FillTargetFactories(registry);
            MvxNetworkActivityIndicatorTargetBinding.Register(registry);
        }