Ejemplo n.º 1
0
        private static IDisposable WhenChanged <TProperty>(LambdaExpression propertyToListen, Action <TProperty> listener, object source)
        {
            var sp = ExpressionHelper.GetSourceAndPropertyName <object, TProperty>(source, propertyToListen);

            if (sp.Source is INotifyPropertyChanged npc)
            {
                var propertyName = sp.PropertyName;
                var disposable   = EventBindingHandler <PropertyChangedEventHandler> .Create(
                    (_, e) =>
                {
                    if (propertyName.Equals(e.PropertyName))
                    {
                        if (npc.CanRead(e.PropertyName))
                        {
                            listener?.Invoke((TProperty)npc.Read(e.PropertyName));
                        }
                    }
                },
                    x => npc.PropertyChanged += x,
                    x => npc.PropertyChanged -= x);

                return(disposable);
            }

            return(null);
        }
Ejemplo n.º 2
0
        public void ObserverProperty_Test2()
        {
            var c1 = new Counter();

            int ctr = 0;

            var ev = EventBindingHandler <PropertyChangedEventHandler>
                     .Create(c1, "PropertyChanged", (_, e) =>
            {
                ctr++;
            });

            c1.Count++;

            ev.Dispose();

            Assert.AreEqual(1, ctr);
        }