iter_n_children
  
  Description:
  public abstract int iter_n_children (
TreeIter? iter)
  
 
  
    Returns the number of children that iter has.
    As a special case, if iter is null, then the number of toplevel nodes is returned.
    Parameters:
    
      
        | this | a TreeModel | 
      
        | iter | the TreeIter-struct, or null | 
    
    Returns:
    
      
        | the number of children of iter |