推送宝实时引擎 iOS SDK Hierarchy Class Hierarchy NSObject TREAudioRecorder TREDebug TREEngine TREEventEmitter TREObject TREAudioPlayer TREChannel TREPrivateChannel TREPresenceChannel TREChannelManager TREChatConversation TREChatConversationManager TREChatGroup TREChatGroupManager TREChatManager TREChatMessage TREChatMessageContent TREChatMessageFileContent TREChatMessageImageContent TREChatMessageVideoContent TREChatMessageVoiceContent TREChatMessageLocationContent TREChatMessageTextContent TREConnection TREUser TREChatUser TREPresenceChannelUser TREImageConverter TRELocationManager Constant References TREChatManagerState TREChatMessageState TREClientErrorCode TREConnectionState