www.pudn.com > uCGUI3.24-MemDev-for-3.90a.rar > GUIDEV_Clear.c

/*! @file GUIDEV_Clear.c 
 *  Implementation of memory devices, add. module  
 * 
 *  @author hiber modified 
 *  @author Copyleft (C) 1981-2006, All Rights Givenup 
 *  @date 04/18/2006 
 *  @version  
 * 
 *  @note  
 *  @attention  
 *  @warning  
 *  @bug 
 * 
 *  @todo 
 *  @example  
 *  @see 
 */ 
#include "GUI_Protected.h" 
#include "GUIDebug.h" 
#include  
 
#if GUI_SUPPORT_MEMDEV 
 
extern void * _GUI_ALLOC_h2p_Lock(GUI_HMEM hMem); 
#define GUI_ALLOC_H2P(h)          _GUI_ALLOC_h2p_Lock(h) 
#define GUI_ALLOC_FREE(handle)    GUI_ALLOC_Free(handle) 
#define GUI_ALLOC_LOCK(handle)    _GUI_ALLOC_h2p_Lock(handle) 
#define GUI_ALLOC_UNLOCK(handle) 
 
#ifdef GUI_USAGE_H2P 
    #undef GUI_USAGE_H2P 
    #define GUI_USAGE_H2P(h) ((GUI_USAGE*)_GUI_ALLOC_h2p_Lock(h))  
#endif 
 
#ifdef GUI_MEMDEV_H2P 
    #undef GUI_MEMDEV_H2P 
    #define GUI_MEMDEV_H2P _GUI_ALLOC_h2p_Lock 
#endif 
 
////////////////////////////////////////////////////////////////////////// 
 
//! 将存储设备的所有内容标志为“未改变的”。 
//! @param hMem 存储设备的句柄 
//! @note 使用GUI_MEMDEV_CopyToLCD 的下一步绘图操作是， 只有在GUI_MEMDEV_Clear 和 
//!       GUI_MEMDEV_CopyToLCD 之间有字节改变的情况才进行写操作。 
void GUI_MEMDEV_Clear(GUI_MEMDEV_Handle hMem) 
{ 
    if (!hMem) 
    { 
        if ((hMem = GUI_Context.hDevData) == 0) 
        { 
            return ;// 设备数据指针为NULL 
        } 
    } 
 
 
    // 大括号用于建立下面的局部变量 
    { 
        GUI_MEMDEV *pDev = GUI_MEMDEV_H2P(hMem);// 得到句柄指向的实际内存指针 
        GUI_USAGE_h hUsage = pDev->hUsage; 
 
        if (hUsage) 
        { 
            GUI_USAGE *pUsage = GUI_USAGE_H2P(hUsage); 
            GUI_USAGE_Clear(pUsage);// avoid compile warning 
        }  
        /* else  
        { 
            GUI_Clear(); 
        }*/ 
    } 
 
} 
 
#else 
 
void GUIDEV_Clear(void)  
{ 
    // avoid empty object files 
}  
 
#endif /* GUI_MEMDEV_SUPPORT */