// implements CellAreaLayoutManager
        // ------------------------------------------------------------------------
        public virtual void AddLayoutComponent(CellAreaComponent comp
			, object constraint)
        {
            string name = (string)constraint;
            if (name == null)
            {
                name = CENTER;
            }
            if (CENTER.Equals(name))
            {
                center = comp;
            }
            else
            {
                if (NORTH.Equals(name))
                {
                    north = comp;
                }
                else
                {
                    if (SOUTH.Equals(name))
                    {
                        south = comp;
                    }
                    else
                    {
                        if (EAST.Equals(name))
                        {
                            east = comp;
                        }
                        else
                        {
                            if (WEST.Equals(name))
                            {
                                west = comp;
                            }
                            else
                            {
                                throw new System.ArgumentException("cannot add to layout: unknown constraint: " +
                                     name);
                            }
                        }
                    }
                }
            }
        }
        public virtual void Add(CellAreaComponent comp, object constraint
			)
        {
            if (comp == null)
            {
                throw new System.ArgumentException();
            }
            if (comp.GetParent() != null)
            {
                // remove from old parent first
                comp.GetParent().Remove(comp);
            }
            comp._inv_setParent(this);
            this.components.Add(comp);
            if (layoutMgr != null)
            {
                layoutMgr.AddLayoutComponent(comp, constraint);
            }
        }
 public virtual void RemoveLayoutComponent(CellAreaComponent comp)
 {
 }
 // ------------------------------------------------------------------------
 public virtual void AddLayoutComponent(CellAreaComponent comp, object constraint)
 {
 }
 public virtual void Add(CellAreaComponent comp)
 {
     Add(comp, null);
 }
 // fireContainerEvent(ContainerEvent.COMPONENT_ADDED, this, comp);
 public virtual void Remove(CellAreaComponent comp)
 {
     if (comp == null)
     {
         throw new System.ArgumentException();
     }
     int index = components.IndexOf(comp);
     if (index == -1)
     {
         throw new System.ArgumentException("can not remove component: component not found as child!"
             );
     }
     if (layoutMgr != null)
     {
         layoutMgr.RemoveLayoutComponent(comp);
     }
 }
        public virtual void RemoveLayoutComponent(CellAreaComponent
			 comp)
        {
            if (comp == center)
            {
                center = null;
            }
            else
            {
                if (comp == north)
                {
                    north = null;
                }
                else
                {
                    if (comp == south)
                    {
                        south = null;
                    }
                    else
                    {
                        if (comp == east)
                        {
                            east = null;
                        }
                        else
                        {
                            if (comp == west)
                            {
                                west = null;
                            }
                        }
                    }
                }
            }
        }