public AsyncEvent <CollectionChanges <K> > Observe <K>(Expression <Func <T, IStateList <K> > > property)
{
var prop = property.GetProperty();
if (_events.ContainsKey(prop))
{
return(_events[prop] as AsyncEvent <CollectionChanges <K> >);
}
var val = (List <K>)_state[prop];
var ae = new AsyncEvent <CollectionChanges <K> >(Changes.Init(val))
.OnSubscribe(async cb => await cb.Invoke(Changes.Init((List <K>)_state[prop])));
_events.Add(prop, ae);
return(ae);
}
public ServiceCollectionField(IEnumerable <T> values = null)
{
if (values != null)
{
_items = new List <T>(values);
}
else
{
_items = new List <T>();
}
Changed = new AsyncEvent <CollectionChanges <T> >(Changes.Init(_items))
// instead of returning the latest change, on subscribe, we return a reset to the entire list
.OnSubscribe(async cb =>
{
await cb.Invoke(Changes.Init(_items));
});
}