/// <summary>
/// Subscribes a given method to any changes in dependencies.
/// </summary>
/// <param name="subscribe">A method that takes in a Cell as an argument.</param>
/// <returns></returns>
private bool Subscribe(Action <Cell> subscribe)
{
if (subscribeCallback == null)
{
subscribeCallback = subscribe;
}
else
{
//Unsubscribe to start fresh.
Unsubscribe();
}
//We have all dependencies, so if the owner is in it, there's a problem.
if (Dependencies.Contains(Owner.Name))
{
ErrorCallback(Owner);
return(false);
}
subscribeCallback = subscribe;
//Subscribe to all direct dependencies.
foreach (Dependency dependency in Dependencies.Cast <DictionaryEntry>().Select(d => d.Value as Dependency).Where(dependency => dependency.IsDirect))
{
dependency.Cell.Changed += subscribeCallback;
}
return(true);
}
/// <summary>
/// Unsubscribes from all dependencies.
/// </summary>
public void Unsubscribe()
{
if (subscribeCallback == null)
{
return;
}
foreach (Dependency dependency in Dependencies.Cast <DictionaryEntry>().Select(d => d.Value as Dependency).Where(dependency => dependency.IsDirect))
{
dependency.Cell.Changed -= subscribeCallback;
}
subscribeCallback = null;
}