wg_listbox.h

一个小巧的嵌入式图形系统wGUI, 可以用VC编译

// wg_listbox.h
//
// CListBox interface
//
//
// Copyright (c) 2002 Rob Wiskow
// [e-mail]
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//


#ifndef _WG_LISTBOX_H_
#define _WG_LISTBOX_H_

#include "wg_window.h"
#include "wg_painter.h"
#include "wg_renderedstring.h"
#include "wg_scrollbar.h"
#include <vector>


namespace wGui
{

//! A listbox item

struct SListItem
{
public:
	//! Standard constructor
	SListItem(std::string sItemTextIn, void* pItemDataIn = 0, CRGBColor ItemColorIn = DEFAULT_LINE_COLOR) :
		sItemText(sItemTextIn), pItemData(pItemDataIn), ItemColor(ItemColorIn) { }

	std::string sItemText;  //!< The displayed text for the item
	void* pItemData;  //!< A pointer to void that can be used as a data pointer
	CRGBColor ItemColor;  //!< The color to display the item in
};


//! A simple listbox class

//! The button will generate CTRL_VALUECHANGE messages when a different listbox item is selected
//! The iNewValue of the message is the index of the item that was selected

class CListBox : public CWindow
{
public:
	//! Constructs a new listbox
  	//! \param WindowRect A CRect that defines the outer limits of the control
	//! \param pParent A pointer to the parent window
	//! \param bSingleSelection If true, only one item can be selected at a time, defaults to false
	//! \param iItemHeight The height of the items in the list, defaults to 15
	//! \param pFontEngine A pointer to the font engine to use when drawing the control
	//! If this is left out (or set to 0) it will use the default font engine specified by the CApplication (which must be set before instantiating this object)
	CListBox(const CRect& WindowRect, CWindow* pParent, bool bSingleSelection = false, unsigned int iItemHeight = 15, CFontEngine* pFontEngine = 0);

	//! Standard destructor
	virtual ~CListBox(void);

	//! \return The height of the items in the listbox
	unsigned int GetItemHeight(void) { return m_iItemHeight; }

	//! \param iItemHeight The height of the items in the listbox
	void SetItemHeight(unsigned int iItemHeight);

	//! Adds a new item to the list
	//! \param ListItem A SListItem structure with the data for the item
	//! \return The index of the added item
	int AddItem(SListItem ListItem);

	//! Returns the desired item
	//! \param iItemIndex The index of the item to check
	//! \return A reference to the SListItem struct
	SListItem& GetItem(int iItemIndex) { return m_Items[iItemIndex]; }

	//! Remove an item from the list
	//! \param iItemIndex The index of the item to remove
	void RemoveItem(int iItemIndex);

	//! Remove all items from the list
	void ClearItems(void);

	//! \return The number of items in the list
	int Size(void) { return static_cast<int>(m_Items.size()); }

	//! \param iItemIndex The index of the item to check
	//! \return true if the item is selected
	bool IsSelected(int iItemIndex) { return m_SelectedItems[iItemIndex]; }

	//! Set an item as selected
	//! \param iItemIndex The index of the item to change
	//! \param bSelected Will select the item if true, or unselect if false
	void SetSelection(int iItemIndex, bool bSelected) { m_SelectedItems[iItemIndex] = bSelected; }

	//! Set the selection for all of the items at once
	//! \param bSelected Will select all items if true, or unselect if false
	void SetAllSelections(bool bSelected);

	//! Set the dropdown window this is a part of
	//! \param pDropDown A pointer to the dropdown window
	void SetDropDown(CWindow* pDropDown) { m_pDropDown = pDropDown; }


	// CWindow overrides
	//! Draws the button and renders the button label
	virtual void Draw(void) const;

	//! Giving a control a new WindowRect will move and resize the control
	//! \param WindowRect A CRect that defines the outer limits of the control
	virtual void SetWindowRect(const CRect& WindowRect);

	//! This is called whenever the listbox is clicked on by the mouse
	//! Only the topmost window that bounds the point will be called by the system
	//! \param Point The point where the mouse clicked
	//! \param Button A bitfield indicating which button the window was clicked with
	//! \return True if it's in the bounds of the listbox
	virtual bool OnMouseButtonDown(CPoint Point, unsigned int Button);

	//! This is called whenever the a mouse button is released in the listbox
	//! Only the topmost window that bounds the point will be called by the system
	//! \param Point The point where the mouse clicked
	//! \param Button A bitfield indicating which button the window was clicked with
	//! \return True if it's in the bounds of the listbox
	virtual bool OnMouseButtonUp(CPoint Point, unsigned int Button);


	// CMessageClient overrides
	//! CListBoxes handle MOUSE_BUTTONDOWN, MOUSE_BUTTONUP and CTRL_VALUECHANGE messages
	//! \param pMessage A pointer to the message
	virtual bool HandleMessage(CMessage* pMessage);


protected:
	CFontEngine* m_pFontEngine;  //!< A pointer to the font engine to use to render the text
	CScrollBar* m_pVScrollbar;  //!< A pointer to the vertical scrollbar
	unsigned int m_iItemHeight;  //!< The height of the items in the list
	int m_iFocusedItem;  //!< The currently focused item
	std::vector<SListItem> m_Items;  //!< The list of items
	std::vector<bool> m_SelectedItems;  //!< A vector of booleans indicating which items are selected
	std::vector<CRenderedString> m_RenderedStrings;  //!< A vector of the rendered strings
	const bool m_bSingleSelection;  //!< If true, only one item can be selected at a time
	CWindow* m_pDropDown;  //!< A pointer to the dropdown control if this a part of one


private:
	void operator=(CListBox) { }  //!< The assignment operator is not allowed for CWindow derived objects
};

}

#endif  // _WG_LISTBOX_H_