# 场景1： 初始化
#### 描述
使用投屏SDK业务组件时，需要先完成SDK的基础组件的初始化。
#### 业务流程
1. 调用ShareServiceController::GetInstance() 获取业务调用Controller Huawei::Idea::ShareServiceController\* mShareServiceController = Huawei::Idea::ShareServiceController::GetInstance()
   
2. 初始化日志 const LogInfo logInfo = {LOG_PATH,IDEA_LEVEL_DEBUG,true}; mShareServiceController-\>SetLog(logInfo);
   
3. 自定义事件回调类，继承自Huawei::Idea::IEventHandler, 其中构造函数INotifyUI 入参是抽象类，可由UI 类继承实现，用作向UI通知消息 class IDEA_SHARE_API IShareEventHandler : public Huawei::Idea::IEventHandler{ public: IShareEventHandler (INotifyUI\* evtHandler, ShareServiceController\* controller); \~IShareEventHandler (); void OnError(ShareAppErr errorCode, std::string errorMsg, void\* extralInfo); void OnDiscoverResult(DiscoverResult\* discoverResult); void OnConnectResult(DeviceInfo\* deviceInfo); void OnDisconnectResult(int reason); .... }; class INotifyUI { public: virtual void HandleConnectResult(std::string deviceName) = 0; virtual void HandleDisConnectResult() = 0; virtual void HandleStartSharingResult() = 0; virtual void HandleStopSharingResult() = 0; .... };
   
类之间关系如下图所示：
**图1-7** 类之间关系
![](https://support.huaweicloud.com/ideahub-IdeaShare-SDK/figure/zh-cn_image_0000001253118387.png "点击放大")
4.注册回调类，初始化SDK
```
const AppInfo appInfo = {};   
    mshareEvtHandler = new IShareEventHandler(this,mShareServiceController);   
    int ret = -1;   
    if (NULL != mshareEvtHandler){   
     ret = mShareServiceController->Create(appInfo,mshareEvtHandler);   
    }
```
#### 注意事项
IShareEventHandler是用户自定义回调类，需继承IEventHandler， 实现IEventHandler所有的回调方法。