virtual bool AppendTextColumn( const wxString &label, size_t model_column );
virtual bool AppendToggleColumn( const wxString &label, size_t model_column );
virtual bool AppendProgressColumn( const wxString &label, size_t model_column );
virtual bool AppendDateColumn( const wxString &label, size_t model_column );
virtual bool AppendTextColumn( const wxString &label, size_t model_column );
virtual bool AppendToggleColumn( const wxString &label, size_t model_column );
virtual bool AppendProgressColumn( const wxString &label, size_t model_column );
virtual bool AppendDateColumn( const wxString &label, size_t model_column );