> ## Documentation Index
> Fetch the complete documentation index at: https://docs.duix.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Key interfaces

> Core Objective-C interfaces and delegate callbacks provided by the Duix iOS SDK.

## Overview

This section lists the **primary interfaces** and **delegate callbacks**\
used to integrate and control the **Duix iOS SDK**.\
These APIs cover initialization, session control, speech interaction,\
and real-time audio-video event handling.

***

## SDK Core Interfaces

```objective-c theme={null}
/**
 * SDK initialization
 *
 * @param appId          Application ID
 * @param appKey         Application key
 * @param conversationId Session ID
 * @param block          Initialization callback
 */
- (void)initWithAppId:(NSString *)appId
               appKey:(NSString *)appKey
        conversationId:(NSString *)conversationId
                block:(void (^)(BOOL isSuccee, NSString *errorMsg))block;

/**
 * Start session
 */
- (void)toStart;

/**
 * End session
 */
- (void)toStop;

/**
 * Speak with text
 *
 * @param text      Text content
 * @param interrupt Whether to interrupt the previous speech
 */
- (void)commandEventWithText:(NSString *)text interrupt:(BOOL)interrupt;

/**
 * Speak with audio URL
 *
 * @param audioUrl  Audio URL
 * @param interrupt Whether to interrupt the previous speech
 */
- (void)commandEventWithAudioUrl:(NSString *)audioUrl interrupt:(BOOL)interrupt;

/**
 * Ask a question (text)
 *
 * @param text      Text content
 * @param interrupt Whether to interrupt the previous speech
 */
- (void)commandAskWithText:(NSString *)text interrupt:(BOOL)interrupt;

/**
 * Interrupt current speech
 */
- (void)toBreakDigital;

/**
 * Microphone capture control
 *
 * @param isEnabled YES to enable microphone pickup, NO to mute
 */
- (void)setMute:(BOOL)isEnabled;

/**
 * Mute or unmute digital human audio
 *
 * @param enable YES to mute, NO to unmute
 */
- (void)toSpeakerMute:(BOOL)enable;


```

SDK Delegate: DigitalViewDelegate
The delegate provides callbacks for SDK events such as loading progress,
speech recognition, playback status, and WebRTC connection changes.

```objective-c theme={null}
@protocol DigitalViewDelegate <NSObject>

/**
 * Load digital human resources
 *
 * @param isSuccess Whether loading succeeded
 * @param progress  Loading progress
 */
- (void)onVideoShow:(BOOL)isSuccess progress:(float)progress;

/**
 * Error callback
 *
 * @param errorCode Error code
 * @param errorMsg  Error message
 */
- (void)onError:(NSInteger)errorCode errorMsg:(NSString *)errorMsg;

@optional

/**
 * ASR start
 */
- (void)toWebrtcAsrStart;

/**
 * ASR result
 *
 * @param asrText  Recognized text
 * @param isFinish Whether recognition has finished
 */
- (void)toWebrtcAsrText:(NSString *)asrText isFinish:(BOOL)isFinish;

/**
 * Speak start
 *
 * @param dict Dictionary containing speech start info
 */
- (void)toSpeakStart:(NSDictionary *)dict;

/**
 * Speak text
 *
 * @param dict Dictionary containing speech text info
 */
- (void)toSpeakText:(NSDictionary *)dict;

/**
 * Speak stop
 *
 * @param dict Dictionary containing speech stop info
 */
- (void)toSpeakStop:(NSDictionary *)dict;

/**
 * TTS speak start
 *
 * @param dict Dictionary containing TTS start info
 */
- (void)toTTSSpeakStart:(NSDictionary *)dict;

/**
 * TTS speak stop
 *
 * @param dict Dictionary containing TTS stop info
 */
- (void)toTTSSpeakStop:(NSDictionary *)dict;

/**
 * Controller ends the call and sends a bye event
 */
- (void)onByeBye;

/**
 * Remote video communication completed
 */
- (void)onRTCReomteSuccess;

/**
 * Audio load result
 *
 * @param isSuccess Whether loading succeeded
 */
- (void)onAudioShow:(BOOL)isSuccess;

/**
 * WebRTC connection state changed
 *
 * @param state RTCIceConnectionState
 */
- (void)didIceConnectionChange:(RTCIceConnectionState)state;

/**
 * Rendering endpoint information retrieved
 *
 * @param ID   Identifier
 * @param name Name
 */
- (void)onRender:(NSString *)ID name:(NSString *)name;

/**
 * Local video stream capture
 *
 * @param capturer Video capturer
 * @param frame    Captured frame
 */
- (void)capturer:(RTCVideoCapturer *)capturer didCaptureVideoFrame:(RTCVideoFrame *)frame;

/**
 * Remote audio stream buffer
 *
 * @param sampleBuffer Audio buffer reference
 */
- (void)onRemoteAudioBuffer:(CMSampleBufferRef)sampleBuffer;

@end
```