# SDK使用
1. 创建引擎并初始化。 
   域名不需要设置，由SDK自动获取。**appId** 获取方法请参见[创建应用](https://support.huaweicloud.com/usermanual-rtc/rtc_04_0001.html)。
   ```
   _rtcEngine = [HWRtcEngine sharedEngine];
   HWRtcEngineConfig * cfg = [[HWRtcEngineConfig alloc]init];
   cfg.appId = appid;// appId需在控制台中创建应用后获取
   cfg.domain = domain;// 该字段已废弃，不需要再传值
   cfg.countryCode = rtcCountryCode;// 可以根据Grs国家码对照表传值，建议传"CN"
   cfg.enableHaTrace = YES;
   cfg.logLevel = HWRtcLogLevelDebug;//输出DEBUG级别日志
   cfg.logPath = [NSString stringWithFormat:@"%@/",logFilePath];//日志存储路径
   cfg.enableLog = YES;//开启日志
   cfg.logSize = 10*1024;
   cfg.muteAudioRoute = NO;//远端音频路由
   [_rtcEngine initWithConfig:cfg];
   ```
   
   
2. 设置本地窗口。 
   ```
   HWRtcVideoCanvas *canvas = [[HWRtcVideoCanvas alloc] init];    
   canvas.view = [[UIView alloc] initWithFrame:CGRectMacke(0, 0, 90, 160)];//iOS
   //canvas.view = [[NSView alloc] initWithFrame:NSMakeRect(0, 0, 90, 160)];//macOS
   canvas.uid  = @"HW";    
   [_rtcEngine setupLocalVideo:canvas viewMode:HWRtcVideoDisplayModeFit];
   ```
   
   
3. 加入房间。 
   ```
   HWRtcJoinParam *joinParam = [[HWRtcJoinParam alloc]init];
   NSString *authorization = @"";// 鉴权信息
   joinParam.role  = HWRtcRoleJoiner;
   joinParam.userId = @"HW"; // userId用于标识同一房间的不同用户
   joinParam.userName = @"HW";// 用户昵称，如无特殊需求，保持和userId一致即可
   joinParam.scenario = 1;
   joinParam.authorization = authorization;
   joinParam.ctime = time;
   joinParam.roomId = roomid;
   joinParam.autoSubscribeAudio = YES;//是否主动订阅音频
   joinParam.autoSubscribeVideo  = NO ;//默认-关闭
   BOOL result = [self.rtcEngine joinRoom:joinParam ];
   ```
   joinParam：入会参数，包含用户ID、用户名、房间号、认证信息、ctime、是否自动订阅音频和视频、SFU类型、场景和用户角色，具体请参见[HWRtcJoinParam](https://support.huaweicloud.com/csdk-rtc/rtc_05_0082.html#rtc_05_0082__section1565345782011)。
   
   
4. 监听远端用户加入房间，并设置远端窗口。 
   ```
   -(void)onRemoteUserOnline:(NSString*)roomId userId:(NSString*)userId userName:(NSString*)userName{
       if([userId isEqualToString:localUid]){
           return;
       }
            dispatch_async(dispatch_get_main_queue(),
                             {         
                UIView *videoView = [[UIVIew alloc] initWithFrame:CGRectMake(0, 0, 90, 160)];//iOS
                //NSView *videoView = [[NSView alloc] initWithFrame:NSMakeRect(0, 0, 90, 160)];//macOS
                [self.view addSubview:videoView];
                 HWRtcVideoCanvas *canvas = [[HWRtcVideoCanvas alloc] init];    
                 canvas.uid  = userId;  
                 canvas.view = videoView;
                 int result = [self.rtcEngine startRemoteStreamView:canvas  treamType:self.streamType];
               if (result == 0) {
                    [self.rtcEngine updateRemoteRenderMode:userId displayMode:HWRtcVideoDisplayModeFit mirrorMode:HWRtcVideoMirrorTypeDisable ];
                }
                [self.viewsArray addObject:canvas];
           });
       }
   ```
   
   
5. 监听远端用户离开房间，并删除远端窗口。 
   ```
   - (void)onRemoteUserOffline:(NSString *)roomId userId:(NSString *)userId reason:(NSInteger)reason
   {
       dispatch_async(dispatch_get_main_queue(),
       ^{
           for (HWRtcVideoCanvas * canvas in self.viewsArray) {
               if ([userId isEqualToString:canvas.uid]) {
                [self.viewsArray removeObject:canvas];
               }
           }
       });
   }
   ```
   
   
6. 离开房间。 
   ```
   [_rtcEngine leaveRoom];
   ```