public ObserverHandle Alloc()
{
var handle = new ObserverHandle();
Add(handle);
return(handle);
}
public ObserverHandle Observe <T>(IObserverList <T> observable, T observer)
{
ObserverHandle handle = null;
Observe(ref handle, observable, observer);
return(handle);
}
public void Unobserve(ObserverHandle handle)
{
if (handle != null)
{
handle.Dispose();
handles.Remove(handle);
}
}
public void Add(ref ObserverHandle handle, T observer)
{
if (handle == null)
{
handle = new ObserverHandle();
}
DebugOnly.Check(observer != null, "Observer is null.");
DebugOnly.Check(handle.List == null, "Handle is already in use.");
handle.Index = list.Count;
handle.List = this;
list.Add(new Item {
handle = handle, observer = observer
});
}
public void Remove(ObserverHandle handle)
{
DebugOnly.Check(handle != null, "Handle is null.");
DebugOnly.Check(handle.List == this, "Handle is not registered with this list.");
int lastIndex = list.Count - 1;
if (handle.Index != lastIndex)
{
var replacement = list[lastIndex];
list[handle.Index] = replacement;
replacement.handle.Index = handle.Index;
}
handle.List = null;
list.RemoveAt(lastIndex);
}
void IObserverList.Add(ref ObserverHandle handle, object observer)
{
if (observer is T typedObserver)
{
Add(ref handle, typedObserver);
}
else
{
if (observer == null)
{
DebugOnly.Error("Observer is null.");
}
else
{
DebugOnly.Error($"Was expecting type {typeof(T)}, got type {observer.GetType().Name}.");
}
}
}
public void Observe <T>(ref ObserverHandle handle, IObserverList <T> observable, T observer)
{
observable.Add(ref handle, observer);
Add(handle);
}
public void Add(ObserverHandle handle)
{
handles.Add(handle);
}
protected void Unobserve(ObserverHandle handle)
{
Observers.Unobserve(handle);
}
protected void Observe <O>(ref ObserverHandle handle, IObserverList <O> observable)
where O : class
{
Observers.Observe(ref handle, observable, this as O);
}
