/// <summary>
/// Register a child <see cref="ObserverManager"/>. "ChangeObserved" events fired by children will bubble up and get re-fired by this manager.
/// <para></para>
/// <see cref="IsEnabled"/> is set to false, the child is already added or is null this will have no effect!
/// </summary>
/// <param name="child">The child to add and observe</param>
public void RegisterChild(ObserverManager child)
{
if (child == null || !IsEnabled)
{
return;
}
if (!children.Any(x => x.guid == child.guid))
{
children.Add(child);
child.ChangeObserved += Observer_ChangeObserved;
child.RegisterParent(this);
}
}
/// <summary>
/// Unregister a child <see cref="ObserverManager"/> if registered.
/// <para></para>
/// If the child is null or isn't registered this will have no effect!
/// </summary>
/// <param name="child">The child to remove</param>
public void UnregisterChild(ObserverManager child)
{
if (child == null)
{
return;
}
int index = children.FindIndex(x => x.guid == child.guid);
if (index > -1)
{
child.UnregisterParent();
child.ChangeObserved -= Observer_ChangeObserved;
children.RemoveAt(index);
}
}
/// <summary>
/// Compares two <see cref="ObserverManager"/> and returns if they match.
/// </summary>
/// <param name="changeManager">The manager to compare this to</param>
/// <returns>Returns true if both <see cref="ObserverManager"/> match, otherwise false</returns>
public bool Compare(ObserverManager changeManager)
{
foreach (var observer in ChangeObservers)
{
var targetObserver = changeManager.ChangeObservers.FirstOrDefault(x => x.PropertyName == observer.PropertyName);
if (targetObserver == null ||
observer.GetOriginalValue() == null && targetObserver.GetOriginalValue() == null ||
(observer.GetOriginalValue() == null && targetObserver.GetOriginalValue() != null) ||
(observer.GetOriginalValue() != null && targetObserver.GetOriginalValue() == null) ||
!observer.GetOriginalValue().Equals(targetObserver.GetOriginalValue()))
{
return(true);
}
}
return(false);
}
private void UnregisterParent()
{
parent = null;
}
private void RegisterParent(ObserverManager parent)
{
this.parent = parent;
}
