在开始游戏应用开发之前，我们先搞一个简单的应用，目的是把菜单操作与应用启动之间打磨平顺。

这里，我们做一个关于About页面即可。

1、菜单项JSON的定义：

[{"t": "关于","i": "menu/test16.png","d": 102,"g": {},"s": []}
]

其中，"d": 102  是这个应用的ID号。

2、实现About页面

About.h

class About : public IScean
{public:About();   ~About();  SceanResult tick(u32 ticks);int scean_init(cJSON* param);
private:u16 colorIndex;DisplayOption option1 = {FONT_SIZE_1516, WHITE, BLACK, 0, 0};DisplayOption option2 = {FONT_SIZE_1516, YELLOW, BLACK, 0, 0};u32 _aboutInterval;
};

About.cpp

About::About(void)
{
}About::~About(void)
{printf("Destory About.\n");
}int About::scean_init(cJSON*  param){clear_screen();Display_String(240, 260, &option2, "深圳市杨梅科技有限公司");show_status_info("EXIT:返回");setKeyAdepterIntervalAll(100);return 0;
}#define AboutInterval 10SceanResult About::tick(u32 ticks){if(KEY_EXIT) {printf("goto top menu from About.\n");return SceanResult_EXIT;}if(_aboutInterval > ticks){_aboutInterval -= 	ticks;return SceanResult_Done;}_aboutInterval = AboutInterval;colorIndex+=3;option1.foreColor = cvColorIdx2RGB(colorIndex);Display_String(50, 100, &option1, R"( __  ______  __  ____  ______  ____  ______  __ )");Display_String(50, 116, &option1, R"( \ \/ / __ \/ / / /  \/ / __ \/    \/ __ \ \/ / )");Display_String(50, 132, &option1, R"(  \  / /_/ / /_/ / /\  / /_/ / / / / /_/ /\  /  )");Display_String(50, 148, &option1, R"(  / /\____/\____/_/ /_/\__  /_/_/_/\___,_\/ /   )");Display_String(50, 164, &option1, R"( /_/                  /____/             /_/    )");return SceanResult_Done;
}

3、在menu.cpp中根据ID启动该应用

。。。#define SceanId_About 102。。。SceanResult Menu::tick(u32 ticks){if(KEY_EXIT){ // 返回cJSON*  currentMenu =  (cJSON *)menuList->prev->data;if(	currentMenu == menuRoot) return SceanResult_Done;ListPopBack(menuList);showMenu ();return SceanResult_Done;}if(KEY_SEL){ //进入cJSON* item =  (cJSON*) ctlList->selectItem()->tag;int sceanId = cJSON_GetObjectItem(item,"d")->valueint;if(sceanId!= 0){IScean *scean =createScean(sceanId);if(scean !=NULL){scean->scean_init(cJSON_GetObjectItem(item,"g"));ListPushBack(sceanList, scean);}return SceanResult_Done;}cJSON* sitem =  cJSON_GetObjectItem(item,"s");if(cJSON_GetArraySize(sitem) > 0){ListPushBack(menuList, sitem);			showMenu();return SceanResult_Done;}return SceanResult_Done;}ctlList->tick(ticks);ran_max(10);return SceanResult_Done;
}IScean* Menu::createScean(u32 idx){switch (idx) {case SceanId_About:return new About();}return NULL;
}

注意这个地方启动应用：

if(sceanId!= 0){
            IScean *scean =createScean(sceanId);
            if(scean !=NULL){
                scean->scean_init(cJSON_GetObjectItem(item,"g"));
                ListPushBack(sceanList, scean);
            }
            return SceanResult_Done;
        }

没有做完全的动态加载，只是实现了按需实例化应用。后面再研究能不能像安卓那样加载应用。

看看效果：