ceguiscrollbar.h

OGRE开发包的依赖包

		position changes will is (pageSize - overlapSize).

	\note
		The value set has no meaning within the Gui system, it is left up to the
		application to assign appropriate values for the application specific use of
		the scroll bar.

	\param page_size
		float value specifying the page size.

	\return
		Nothing.
	*/
	void	setPageSize(float page_size);


	/*!
	\brief
		Set the step size for this scroll bar.
		
		The step size is typically a single unit of data that can be displayed, this is the
		amount the position will change when you click either of the arrow buttons on the
		scroll bar.  (this could be 1 for a single line of text, for example).

	\note
		The value set has no meaning within the Gui system, it is left up to the
		application to assign appropriate values for the application specific use of
		the scroll bar.

	\param step_size
		float value specifying the step size.

	\return
		Nothing.
	*/
	void	setStepSize(float step_size);


	/*!
	\brief
		Set the overlap size for this scroll bar.
		
		The overlap size is the amount of data from the end of a 'page' that will
		remain visible when the position is moved by a page.  This is usually used
		so that the user keeps some context of where they were within the document's
		data when jumping a page at a time.

	\note
		The value set has no meaning within the Gui system, it is left up to the
		application to assign appropriate values for the application specific use of
		the scroll bar.

	\param overlap_size
		float value specifying the overlap size.

	\return
		Nothing.
	*/
	void	setOverlapSize(float overlap_size);


	/*!
	\brief
		Set the current position of scroll bar within the document.

		The range of the scroll bar is from 0 to the size of the document minus the
		size of a page (0 <= position <= (documentSize - pageSize)), any attempt to
		set the position outside this range will be adjusted so that it falls within
		the legal range.

	\note
		The returned value has no meaning within the Gui system, it is left up to the
		application to assign appropriate values for the application specific use of
		the scroll bar.

	\param position
		float value specifying the position of the scroll bar within its
		document.

	\return
		Nothing.
	*/
	void	setScrollPosition(float position);


	/*************************************************************************
		Construction / Destruction
	*************************************************************************/
	/*!
	\brief
		Constructor for Scrollbar objects
	*/
	Scrollbar(const String& type, const String& name);


	/*!
	\brief
		Destructor for Scrollbar objects
	*/
	virtual ~Scrollbar(void);


protected:
	/*************************************************************************
		Implementation Methods
	*************************************************************************/
	/*!
	\brief
		update the size and location of the thumb to properly represent the current state of the scroll bar
	*/
	void	updateThumb(void);


	/*!
	\brief
		return value that best represents current scroll bar position given the current location of the thumb.

	\return
		float value that, given the thumb widget position, best represents the current position for the scroll bar.
	*/
	float	getValueFromThumb(void) const;


	/*!
	\brief
		Given window location \a pt, return a value indicating what change should be 
		made to the scroll bar.

	\param pt
		Point object describing a pixel position in window space.

	\return
		- -1 to indicate scroll bar position should be moved to a lower value.
		-  0 to indicate scroll bar position should not be changed.
		- +1 to indicate scroll bar position should be moved to a higher value.
	*/
	float	getAdjustDirectionFromPoint(const Point& pt) const;


    /*!
    \brief
        update the size and location of the thumb to properly represent the current state of the scroll bar
    */
    //virtual void    updateThumb_impl(void)   = 0;


    /*!
    \brief
        return value that best represents current scroll bar position given the current location of the thumb.

    \return
        float value that, given the thumb widget position, best represents the current position for the scroll bar.
    */
    //virtual float   getValueFromThumb_impl(void) const   = 0;


    /*!
    \brief
        Given window location \a pt, return a value indicating what change should be 
        made to the scroll bar.

    \param pt
        Point object describing a pixel position in window space.

    \return
        - -1 to indicate scroll bar position should be moved to a lower value.
        -  0 to indicate scroll bar position should not be changed.
        - +1 to indicate scroll bar position should be moved to a higher value.
    */
    //virtual float   getAdjustDirectionFromPoint_impl(const Point& pt) const  = 0;


	/*!
	\brief
		handler function for when thumb moves.
	*/
	bool	handleThumbMoved(const EventArgs& e);


	/*!
	\brief
		handler function for when the increase button is clicked.
	*/
	bool	handleIncreaseClicked(const EventArgs& e);


	/*!
	\brief
		handler function for when the decrease button is clicked.
	*/
	bool	handleDecreaseClicked(const EventArgs& e);


	/*!
	\brief
		handler function for when thumb tracking begins
	*/
	bool	handleThumbTrackStarted(const EventArgs& e);


	/*!
	\brief
		handler function for when thumb tracking begins
	*/
	bool	handleThumbTrackEnded(const EventArgs& e);


	/*!
	\brief
		Return whether this window was inherited from the given class name at some point in the inheritance hierarchy.

	\param class_name
		The class name that is to be checked.

	\return
		true if this window was inherited from \a class_name. false if not.
	*/
	virtual bool	testClassName_impl(const String& class_name) const
	{
		if (class_name=="Scrollbar")	return true;
		return Window::testClassName_impl(class_name);
	}

    // validate window renderer
    virtual bool validateWindowRenderer(const String& name) const
    {
        return (name == "Scrollbar");
    }

	/*************************************************************************
		New event handlers for slider widget
	*************************************************************************/
	/*!
	\brief
		Handler triggered when the scroll position changes
	*/
	virtual void	onScrollPositionChanged(WindowEventArgs& e);


	/*!
	\brief
		Handler triggered when the user begins to drag the scroll bar thumb. 
	*/
	virtual void	onThumbTrackStarted(WindowEventArgs& e);


	/*!
	\brief
		Handler triggered when the scroll bar thumb is released
	*/
	virtual void	onThumbTrackEnded(WindowEventArgs& e);


	/*!
	\brief
		Handler triggered when the scroll bar data configuration changes
	*/
	virtual void	onScrollConfigChanged(WindowEventArgs& e);


	/*************************************************************************
		Overridden event handlers
	*************************************************************************/
	virtual void	onMouseButtonDown(MouseEventArgs& e);
	virtual	void	onMouseWheel(MouseEventArgs& e);


	/*************************************************************************
		Implementation Data
	*************************************************************************/
	float	d_documentSize;		//!< The size of the document / data being scrolled thorugh.
	float	d_pageSize;			//!< The size of a single 'page' of data.
	float	d_stepSize;			//!< Step size used for increase / decrease button clicks.
	float	d_overlapSize;		//!< Amount of overlap when jumping by a page.
	float	d_position;			//!< Current scroll position.


private:
	/*************************************************************************
		Static Properties for this class
	*************************************************************************/
	static ScrollbarProperties::DocumentSize	d_documentSizeProperty;
	static ScrollbarProperties::PageSize		d_pageSizeProperty;
	static ScrollbarProperties::StepSize		d_stepSizeProperty;
	static ScrollbarProperties::OverlapSize		d_overlapSizeProperty;
	static ScrollbarProperties::ScrollPosition	d_scrollPositionProperty;


	/*************************************************************************
		Private methods
	*************************************************************************/
	void	addScrollbarProperties(void);
};

} // End of  CEGUI namespace section

#if defined(_MSC_VER)
#	pragma warning(pop)
#endif

#endif	// end of guard _CEGUIScrollbar_h_