public void Add(TestingElement item)
 {
     if (item != null)
         this.AddFunctionalChild(item);
 }
 private void InitElements()
 {
     Root = new TestingElement("Root");
     _elements = new List<TestingElement>
     {
         Root,
         new TestingElement("1"),
         new TestingElement("2"),
         new TestingElement("3"),
         new TestingElement("4"),
         new TestingElement("5"),
         new TestingElement("6"),
         new TestingElement("7"),
         new TestingElement("8"),
         new TestingElement("9"),
         new TestingElement("10"),
         new TestingElement("11"),
         new TestingElement("12"),
         new TestingElement("13"),
         new TestingElement("14"),
         new TestingElement("15"),
         new TestingElement("16"),
         new TestingElement("17"),
         new TestingElement("18"),
         new TestingElement("19"),
         new TestingElement("20"),
         new TestingElement("21"),
         new TestingElement("22"),
         new TestingElement("23"),
         new TestingElement("24"),
         new TestingElement("25"),
         new TestingElement("26"),
         new TestingElement("27"),
         new TestingElement("28"),
         new TestingElement("29"),
         new TestingElement("30"),
         new TestingElement("31"),
         new TestingElement("32"),
         new TestingElement("33")
     };
 }
 public void Remove(TestingElement item)
 {
     this.RemoveFunctionalChild(item);
 }