首先定义一个菜单结构
typedef struct menu//定义一个菜单
{
 u8 range_from,range_to; //当前显示的项开始及结束序号
 u8 itemCount;//项目总数
 u8 selected;//当前选择项
 u8 *menuItems[17];//菜单项目
 struct menu **subMenus;//子菜单
 struct menu *parent;//上级菜单 ,如果是顶级则为null
 void (**func)();//选择相应项按确定键后执行的函数 }Menu; Menu MainMenu = { //定义主菜单
 0,3,4,0,//默认显示0-3项，总共4项，当前选择第0项
  {
  "设置1          x10",
  "设置2          x10",
  "输入指令发送    ",
  "查询           x10"
  }
}; Menu searchMenu = {//查询菜单
 0,3,6,0,
 {
  "记帐记录明细    ",
  "未采集记录数    ",
  "设备机号        ",
  "本机IP地址      ",
  "记录空间大小    ",
  "软件版本        "
 }
};
Menu *currentMenu;//当前的菜单

用于显示菜单项
void display(u8 line) //显示菜单项并设置选中的项反白
{
 int i;
 line = 3-(currentMenu->range_to-line);
 Lcd_Fill(0x00);
 for(i = 0;i<4;i++)
 {
  Lcd_Disp(i+1,0,currentMenu->menuItems[i+currentMenu->range_from]);
 }
 highlight(0,line,8,255);//反白显示指定行
}
void func(void)
{

printf("hello ");
}
初始化菜单:
void initMenu()
{
 MainMenu.subMenus = malloc(sizeof(&MainMenu)*4);
 MainMenu.subMenus[0] = NULL;//第1到3项没有子菜单置null,选择后程序会调用func中相应项中的函数
 MainMenu.subMenus[1] = NULL;
 MainMenu.subMenus[2] = NULL;
 MainMenu.subMenus[3] = &searchMenu;//第四项查询有子菜单
 MainMenu.func = malloc(sizeof(&func)*4);
 MainMenu.func[0] = NULL;
 MainMenu.func[1] = NULL;
 MainMenu.func[2] = &func;//当选择了并按了确定，会执行func函数
 MainMenu.func[3] = NULL;
 MainMenu.parent = NULL;//表示是顶级菜单
 
 searchMenu.subMenus = malloc(sizeof(&searchMenu)*6);
 searchMenu.subMenus[0] = searchMenu.subMenus[1] = searchMenu.subMenus[2] = searchMenu.subMenus[3] = searchMenu.subMenus[4] = searchMenu.subMenus[5] = NULL;
 searchMenu.func = malloc(sizeof(&printf)*6);
 searchMenu.func[0] = searchMenu.func[2] = searchMenu.func[2] = searchMenu.func[3] = searchMenu.func[4] = searchMenu.func[5] = NULL;
 searchMenu.parent = &MainMenu;//上一级菜单是MainMenu.进入查询子菜单后按返回键，将会显示这个菜单 项
 
 currentMenu = &MainMenu;
 
}

main

int main(void)
 {
 
  delay_init();
  uart_init(9600);
  Lcd_Init();
  KEY_Init();
  initMenu();
  display(currentMenu->selected);
  while(1)
 {
  key = KEY_Scan();
  if(key == 0)
  {
   delay_ms(10);
   continue;
  }
  printf("key %d is press ",key);
  switch(key)
  {
   case 12://向上
    if(currentMenu->selected == 0)//到了第一项
     break;
    else
    {
     currentMenu->selected--;
     if(currentMenu->selected < currentMenu->range_from)//更新显示的区域
     {
      currentMenu->range_from = currentMenu->selected;
      currentMenu->range_to = currentMenu->range_from+3;
     }
     display(currentMenu->selected);
     break;
    }
   case 8://向下
    if(currentMenu->selected == currentMenu->itemCount-1)
     break;
    else
    {
     currentMenu->selected++;
     if(currentMenu->selected>currentMenu->range_to)
     {
      currentMenu->range_to = currentMenu->selected;
      currentMenu->range_from = currentMenu->range_to-3;
     }
     display(currentMenu->selected);
     break;
    }
   case 4://Enter键
   {
    if(currentMenu->subMenus[currentMenu->selected] !=NULL)
    {
     currentMenu = currentMenu->subMenus[currentMenu->selected];
     display(0);
    }
    else
    {
     if(currentMenu->func[currentMenu->selected] != NULL)
     {
      currentMenu->func[currentMenu->selected]();//执行相应的函数
      display(currentMenu->selected);//返回后恢复原来的菜单状态
     }
    }
    break;
   }
   case 3://返回键
   {
    if(currentMenu->parent!=NULL)//父菜单不为空，将显示父菜单
    {
     currentMenu = currentMenu->parent;
     display(currentMenu->selected);
    }
    break;
   }
   default:
     break;
  }
  delay_ms(10);
 }
 }
运行效果图:

选择查询项：

选择查询项并按确定键后：

此时按返回键，将会返回到第二个图片中的界面