title: Extending a nested class method
body: <p>I have encountered a virtual method in a nested class. </p>
  
  <pre><code>##classone.h
  
  class ClassOne: {
  public:
    class InnerClass{
    public:
        virtual void method1();
        ...
  
  ##classone.cpp
  void ClassOne::InnerClass::method1()
  {
  ...
  }
  </code></pre>
  
  <p>I am subclassing <code>ClassOne</code> and need to extend <code>method1()</code>. What need's to be done with the nested class in that situation?</p>
  
  <p><strong>What I tried</strong></p>
  
  <pre><code>##subclassone.h
  
  class SubClassOne: public ClassOne{
  public:
      virtual void method1();
  
  ##subclassone.cpp
  
  void SubClassOne::InnerClass::method1()
  {
  ##New implementation
  }
  </code></pre>
  
  <p>But that gives a <code>multiple definition of ClassOne::InnerClass::method1()</code>        </p>