/// <summary>
/// Listens for when a property is changed and ensures that the subscription is properly disposed when the system disposes or when the component disposes.
/// </summary>
/// <typeparam name="TComponentType"></typeparam>
/// <typeparam name="TPropertyType"></typeparam>
/// <param name="system">This system to install this listner on, it will get disposed with this one.</param>
/// <param name="select">A selector for the property observable on TComponentType that you wish to listen for.</param>
/// <param name="handler">The method that is invoked when the property changes.</param>
/// <param name="getImmediateValue">The lambda method for retreiving the primtive value, if this is not null, it will immedietly invoke the handler with this value.</param>
/// <param name="onlyWhenChanged">Only invoke the method when the value actually changes rather than when it is set.</param>
public static void PropertyChanged <TComponentType, TPropertyType>(this IEcsSystem system,
Func <TComponentType,
IObservable <TPropertyType> > select,
Action <TComponentType,
TPropertyType> handler, Func <TComponentType, TPropertyType> getImmediateValue = null, bool onlyWhenChanged = false) where TComponentType : class, IEcsComponent
{
if (onlyWhenChanged)
{
system.OnComponentCreated <TComponentType>().DistinctUntilChanged().Subscribe(_ =>
{
select(_).Subscribe(v => handler(_, v)).DisposeWith(_).DisposeWith(system);
if (getImmediateValue != null)
{
handler(_, getImmediateValue(_));
}
}).DisposeWith(system);
}
else
{
system.OnComponentCreated <TComponentType>().Subscribe(_ =>
{
select(_).Subscribe(v => handler(_, v)).DisposeWith(_).DisposeWith(system);
if (getImmediateValue != null)
{
handler(_, getImmediateValue(_));
}
}).DisposeWith(system);
}
}
/// <summary>
/// Listens for when a property is changed and ensures that the subscription is properly disposed when the system disposes or when the component disposes.
/// </summary>
/// <typeparam name="TComponentType"></typeparam>
/// <typeparam name="TPropertyType"></typeparam>
/// <param name="system">This system to install this listner on, it will get disposed with this one.</param>
/// <param name="select">A selector for the property observable on TComponentType that you wish to listen for.</param>
/// <param name="handler">The method that is invoked when the property changes.</param>
/// <param name="getImmediateValue">The lambda method for retreiving the primtive value, if this is not null, it will immedietly invoke the handler with this value.</param>
/// <param name="onlyWhenChanged">Only invoke the method when the value actually changes rather than when it is set.</param>
public static void PropertyChangedEvent <TComponentType, TPropertyType>(this IEcsSystem system,
Func <TComponentType,
IObservable <PropertyChangedEvent <TPropertyType> > > select,
Action <TComponentType,
PropertyChangedEvent <TPropertyType> > handler, Func <TComponentType, TPropertyType> getImmediateValue = null, bool onlyWhenChanged = false) where TComponentType : class, IEcsComponent
{
if (onlyWhenChanged)
{
system.OnComponentCreated <TComponentType>().Subscribe(_ =>
{
select(_).Where(p => !Equals(p.PreviousValue, p.CurrentValue)).Subscribe(v => handler(_, v)).DisposeWith(_).DisposeWith(system);
if (getImmediateValue != null)
{
handler(_, new PropertyChangedEvent <TPropertyType>()
{
CurrentValue = getImmediateValue(_)
});
}
}).DisposeWith(system);
}
else
{
system.OnComponentCreated <TComponentType>().Subscribe(_ =>
{
select(_).Subscribe(v => handler(_, v)).DisposeWith(_).DisposeWith(system);
if (getImmediateValue != null)
{
handler(_, new PropertyChangedEvent <TPropertyType>()
{
CurrentValue = getImmediateValue(_)
});
}
}).DisposeWith(system);
}
}
/// <summary>
/// Listens for when a property is changed and ensures that the subscription is properly disposed when the system disposes or when the component disposes.
/// </summary>
/// <typeparam name="TComponentType"></typeparam>
/// <typeparam name="TPropertyType"></typeparam>
/// <param name="system">This system to install this listner on, it will get disposed with this one.</param>
/// <param name="select">A selector for the property observable on TComponentType that you wish to listen for.</param>
/// <param name="handler">The method that is invoked when the property changes.</param>
/// <param name="getImmediateValue">The lambda method for retreiving the primtive value, if this is not null, it will immedietly invoke the handler with this value.</param>
/// <param name="onlyWhenChanged">Only invoke the method when the value actually changes rather than when it is set.</param>
public static void PropertyChangedEvent <TComponentType, TPropertyType>(this IEcsSystem system,
Func <TComponentType,
IObservable <PropertyChangedEvent <TPropertyType> > > select,
Action <TComponentType,
PropertyChangedEvent <TPropertyType> > handler, Func <TComponentType, TPropertyType> getImmediateValue = null, bool onlyWhenChanged = false) where TComponentType : class, IEcsComponent
{
if (onlyWhenChanged)
{
system.OnComponentCreated <TComponentType>().Subscribe(_ =>
{
select(_).Subscribe(v =>
{
// the next line crashes unity:
//!Equals(v.PreviousValue, v.CurrentValue))
//That is why we got some nastiness here
if (!v.Comparer.Equals(v.PreviousValue, v.CurrentValue))
{
handler(_, v);
}
}).DisposeWith(_).DisposeWith(system);
if (getImmediateValue != null)
{
handler(_, new PropertyChangedEvent <TPropertyType>()
{
CurrentValue = getImmediateValue(_)
});
}
}).DisposeWith(system);
}
else
{
system.OnComponentCreated <TComponentType>().Subscribe(_ =>
{
select(_).Subscribe(v => handler(_, v)).DisposeWith(_).DisposeWith(system);
if (getImmediateValue != null)
{
handler(_, new PropertyChangedEvent <TPropertyType>()
{
CurrentValue = getImmediateValue(_)
});
}
}).DisposeWith(system);
}
}
/// <summary>
/// Listens for when a Reactive Collection's item has been removed, and ensures that the subscription properly disposed when the system disposes or when the component disposes.
/// </summary>
/// <typeparam name="TComponentType"></typeparam>
/// <typeparam name="TPropertyType"></typeparam>
/// <param name="system">This system to install this listner on, it will get disposed with this one.</param>
/// <param name="select">The ReactiveCollection selector.</param>
/// <param name="handler">The method that is invoked when an item is added to the collection</param>
public static void CollectionItemRemoved <TComponentType, TPropertyType>(this IEcsSystem system,
Func <TComponentType,
ReactiveCollection <TPropertyType> > select,
Action <TComponentType,
TPropertyType> handler) where TComponentType : class, IEcsComponent
{
system.OnComponentCreated <TComponentType>().Subscribe(_ =>
{
select(_).ObserveRemove().Subscribe(v => handler(_, v.Value)).DisposeWith(_).DisposeWith(system);
}).DisposeWith(system);
}
/// <summary>
/// Listens for when a Reactive Collection's item has been added, and ensures that the subscription properly disposed when the system disposes or when the component disposes.
/// </summary>
/// <typeparam name="TComponentType"></typeparam>
/// <typeparam name="TPropertyType"></typeparam>
/// <param name="system">This system to install this listner on, it will get disposed with this one.</param>
/// <param name="select">The ReactiveCollection selector.</param>
/// <param name="handler">The method that is invoked when an item is added to the collection</param>
/// <param name="immediate">Should the handler be invoked for every item that is currently in the list?</param>
public static void CollectionItemAdded <TComponentType, TPropertyType>(this IEcsSystem system,
Func <TComponentType,
ReactiveCollection <TPropertyType> > select,
Action <TComponentType,
TPropertyType> handler, bool immediate = false) where TComponentType : class, IEcsComponent
{
system.OnComponentCreated <TComponentType>().Subscribe(_ =>
{
select(_).ObserveAdd().Subscribe(v => handler(_, v.Value)).DisposeWith(_).DisposeWith(system);
if (immediate)
{
foreach (var item in select(_))
{
handler(_, item);
}
}
}).DisposeWith(system);
}
