How to use

addCollectionListener

method

in

com.ochafik.util.listenable.ListenableCollection

public void addCollectionListener(CollectionListener<T> l) {
  if (listeners == null) {
    listeners = new ArrayList<CollectionListener<T>>();
    listenableCollection.addCollectionListener(new CollectionListener<T>() {
      public void collectionChanged(CollectionEvent<T> e) {
        if (listeners != null && !listeners.isEmpty()) {
          Collection<T> filteredElements = e.getElements();
          CollectionEvent<T> filteredEvent = new CollectionEvent<T>(FilteredListenableCollection.this, filteredElements, e.getType(), e.getFirstIndex(), e.getLastIndex());
          for (CollectionListener<T> listener : listeners) {
            listener.collectionChanged(filteredEvent);
          }
        }
      }
    });
  }
  
  listeners.add(l);
}

a.addCollectionListener(listener);
b.addCollectionListener(listener);

public CompoundListenableCollection(ListenableCollection<ListenableCollection<T>> adapted){
final Object wildcardObject = adapted;//Just don't look at it and it won't hurt as much.
delegate = new CompoundCollection<T>((Collection<Collection<? extends T>>)wildcardObject);
adapted.addCollectionListener(outerListener);
}//end constructor

public void addCollectionListener(CollectionListener<V> l) {
  if (collectionSupport == null) {
    collectionSupport = new ListenableSupport<V>();
    if (collection instanceof ListenableCollection<?>) {
      ((ListenableCollection<U>)collection).addCollectionListener(new CollectionListener<U>() {
        public void collectionChanged(CollectionEvent<U> e) {
          // Do not propagate the event if we triggered it
          if (currentlyCausingChange)
            return;
          
          // Only propagate if someone is listening (CollectionSupport already tries not to fire anything when there is no listener, but here we are trying to avoid to create the wrapped elements collection)
          if (collectionSupport == null || !collectionSupport.hasListeners())
            return;
          
          // Adapt the collection of changed / added / removed elements in the event
          collectionSupport.fireEvent(
            AdaptedCollection.this, 
            new AdaptedCollection<U, V>(e.getElements(), AdaptedCollection.this.forwardAdapter, AdaptedCollection.this.backwardAdapter), 
            e.getType(), 
            e.getFirstIndex(), 
            e.getLastIndex());
        }
      });
    }
  }
      
  collectionSupport.addCollectionListener(l);
}

@Override
public void collectionChanged(CollectionEvent<ListenableCollection<T>> e) {
  switch(e.getType()){
  case ADDED:
  for(ListenableCollection<T> coll:e.getElements()){
    delegate.addComponent(coll);
    coll.addCollectionListener(innerListener);
    ls.fireAdded(CompoundListenableCollection.this, coll);
  }//end for(collections added)
  break;
  case REMOVED:
  for(ListenableCollection<T> coll:e.getElements()){
    delegate.removeComponent(coll);
    coll.removeCollectionListener(innerListener);
    ls.fireRemoved(CompoundListenableCollection.this, coll);
  }//end for(collections removed)
  break;
  case UPDATED:
  // ????
  break;
  default:
  break;
  }//end EventTypes
}};