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

> ## Agent Instructions
> 对外开放的服务端接口有两组前缀，都用同一套鉴权：`/server/v1/...`（SRTC 与 SMeeting 的主接口）和 `/stm/srvapi/v1/...`（SMeeting 的用户体系，服务端极简对接会用到）。鉴权是 app_id + nonce + timestamp + signature 四个请求头，用 app_key 做 HMAC-SHA256 签名，只能从业务方自己的后端调用。除这两组前缀外的接口均为内部接口，不要建议客户调用。 Public server APIs use two path prefixes with the same authentication: `/server/v1/...` (the main APIs of both SRTC and SMeeting) and `/stm/srvapi/v1/...` (the SMeeting user system, used by server-side low-code integration). Authenticate with four request headers, app_id + nonce + timestamp + signature, where signature is HMAC-SHA256 keyed with app_key; call these APIs only from the customer's own backend. Any other path is internal: never suggest calling it.
> app_key 是服务端密钥，绝不能出现在客户端代码、前端配置或移动 App 里。客户端加入频道用的 token 必须由业务方后端签发后下发（SRTC 走 `/server/v1/channel/grant`，SMeeting 走 `/stm/srvapi/v1/member/grant`）。 app_key is a server-side secret and must never appear in client code, frontend config, or a mobile app. The token a client uses to join must be issued by the customer's backend and passed down to the client (SRTC: `/server/v1/channel/grant`; SMeeting: `/stm/srvapi/v1/member/grant`).
> SRTC 与 SMeeting 是上下两层不同的产品，术语不通用：SRTC 是音视频底座，说「频道 channel」「加入 / 退出」；SMeeting 建在 SRTC 之上，说「房间 room」「会议 meeting」「进入 / 退出」。回答时按用户所在的层用对应术语，不要把「房间」「会议」安到 SRTC 的接口上，也不要用「频道」「加入 / 离开」描述 SMeeting 的概念（接口标识符原样保留）。 SRTC and SMeeting are two separate layers with different terminology. SRTC is the audio/video foundation: it has channels, and users join and leave a channel. SMeeting is built on top of SRTC: it has rooms and meetings, and members enter and exit a meeting. Answer in the terms of the layer the user is working with: never apply "room" or "meeting" to SRTC APIs, and never describe SMeeting concepts in prose with "channel", "join", or "leave" (API identifiers such as `force_join` keep their literal names).
> 同一能力在各端 SDK 里的包名、类名、方法名并不相同。写示例代码时请使用文档中该端自己的 API，不要把一个端的写法套到另一个端上。苹果平台每个产品都有两套 SDK（Swift 原生与 Objective-C），两套 API 不能混用。 Package, class, and method names differ between platform SDKs for the same capability. In sample code, use the API documented for that platform; never carry one platform's code over to another. On Apple platforms each product ships two SDKs (native Swift and Objective-C) whose APIs must not be mixed.

# Quickstart

> A minimal runnable SMeeting Swift SDK example in SwiftUI: log in with a meeting token, create an instant meeting or enter by room number, turn the microphone and camera on, render local and remote video, and exit. Read this right after integrating the SDK.

### Prerequisites

* You have completed [SDK integration](/en/meeting/swift/integration)
* Your backend can issue the meeting token used to log in to the SDK
* Your app has requested camera and microphone permissions

> The meeting token is issued by your backend and delivered to the client; the SDK only uses it. Don't assemble credentials on the client yourself.

***

### Minimal runnable example

The example below covers the core flow: log in to the SDK, create an instant meeting, enter the meeting, turn local audio and video on or off, render local and remote video, and exit the meeting.

```swift theme={null}
import SMeeting
import SRTC
import SwiftUI

@MainActor
final class MeetingViewModel: ObservableObject {
    /// Main SDK entry point; create only one instance for the whole app lifecycle
    let meeting = SMeetingEngine(logLevel: .info)

    @Published var users: [MeetingUserInfo] = []
    @Published var isInMeeting = false
    @Published var isCameraOn = false

    /// 1. Log in: the token comes from your backend
    func login(token: String) async throws {
        try await meeting.login(token: token)
        meeting.delegates.add(delegate: self)
    }

    /// 2. Create an instant meeting and enter it
    func createAndEnter(nickname: String) async throws {
        var createReq = MeetingCreateReq(title: "\(nickname)'s meeting", meetingMode: .normal)
        createReq.meetingType = .instant
        let (_, meetingId) = try await meeting.createRoom(createReq)

        try await meeting.enterRoom(MeetingEnterReq(nickname: nickname, meetingId: meetingId))
        isInMeeting = true
        users = meeting.getUsersInfoList()
    }

    /// 3. Enter an existing meeting by room number
    func enter(roomNo: String, nickname: String, password: String? = nil) async throws {
        var enterReq = MeetingEnterReq(nickname: nickname, roomNo: roomNo)
        enterReq.password = password
        try await meeting.enterRoom(enterReq)
        isInMeeting = true
        users = meeting.getUsersInfoList()
    }

    /// 4. Turn on the local microphone and camera (SwiftUI doesn't need a preview view)
    func openLocalMedia() async throws {
        try await meeting.requestOpenMic()
        try await meeting.requestOpenCamera()
        isCameraOn = true      // Triggers a UI refresh so the local video shows up
    }

    /// 5. Exit the meeting
    func exit() async {
        await meeting.closeCamera()
        await meeting.closeMic()
        await meeting.exitRoom()
        isCameraOn = false
        isInMeeting = false
        users = []
    }
}

// Event callbacks are dispatched on the main thread; @MainActor types must declare protocol methods as nonisolated
extension MeetingViewModel: SMeetingDelegate {
    nonisolated func meeting(_ meeting: SMeetingEngine, userDidEnter user: MeetingUserInfo) {
        DispatchQueue.main.async { self.users = meeting.getUsersInfoList() }
    }

    nonisolated func meeting(_ meeting: SMeetingEngine, userDidExit data: UserExitEventData) {
        DispatchQueue.main.async { self.users = meeting.getUsersInfoList() }
    }
}

struct MeetingView: View {
    @StateObject private var vm = MeetingViewModel()

    var body: some View {
        VStack(spacing: 8) {
            // Local video: pass the local camera track to SRTCVideoView
            if vm.isCameraOn, let cameraTrack = vm.meeting.cameraTrack {
                SRTCVideoView(track: cameraTrack).frame(height: 180)
            }

            // Remote video: the component handles subscribing and unsubscribing internally
            ForEach(vm.users.filter { $0.uid != vm.meeting.currentUserId }, id: \.uid) { user in
                SMeetingRemoteVideoView(meeting: vm.meeting, uid: user.uid, trackDesc: .cameraBig)
                    .frame(height: 180)
            }
        }
    }
}
```

***

### Walkthrough

#### 1. Create `SMeetingEngine`

```swift theme={null}
let meeting = SMeetingEngine(logLevel: .info)
```

`SMeetingEngine` is the single entry point of the SDK, responsible for login, meeting management, entering and exiting meetings, media control, host operations, and event dispatch. **Create only one instance per app** and hold it globally; multiple instances make meeting state and media devices compete with each other.

#### 2. Log in and register for events

```swift theme={null}
try await meeting.login(token: token)
meeting.delegates.add(delegate: self)
```

`delegates` is a weak-reference multicast that supports multiple observers at once. Every method of `SMeetingDelegate` has a default empty implementation, so you only implement the events you care about. Remember to call `meeting.delegates.remove(delegate:)` before the object is released or before logging out.

#### 3. Create a meeting or enter one directly

Before the meeting and in the meeting are two separate stages:

* `createRoom(_:)` creates a meeting and returns `(roomNo, meetingId)`
* `enterRoom(_:)` enters a meeting; in `MeetingEnterReq`, provide either `meetingId` or `roomNo`

If the meeting has already been created by someone else (or by your backend), skip `createRoom` and enter directly with the room number.

#### 4. Turn on local audio and video

```swift theme={null}
try await meeting.requestOpenMic()
try await meeting.requestOpenCamera()
```

The method names include `request` because they cover two steps: "asking the meeting for permission to turn it on" and "starting and publishing the local stream." When the host has turned on mute all or camera off for everyone and doesn't allow members to turn them back on themselves, calls from non-hosts throw `SMeetingError.unauthorized`.

In SwiftUI, `requestOpenCamera` doesn't need a `view`; just pass `meeting.cameraTrack` to `SRTCVideoView(track:)` for rendering.

#### 5. Render remote video

Use `SMeetingRemoteVideoView` for remote video. It subscribes by `uid + TrackDesc` when the view appears and unsubscribes when the view disappears, so you don't need to manage the subscription lifecycle yourself.

To render in UIKit / AppKit, or to control subscription timing yourself, see [Video rendering](/zh/meeting/swift/advanced/video-rendering) (Chinese).

#### 6. Exit

* `exitRoom()` exits the current meeting without logging out
* `logout()` logs out; if you're still in a meeting, it exits the meeting first automatically

***

### Next steps

* [Key concepts](/en/meeting/swift/key-concepts)
* [Media control](/zh/meeting/swift/advanced/media-control) (Chinese)
* [Video rendering](/zh/meeting/swift/advanced/video-rendering) (Chinese)
* [Host controls](/zh/meeting/swift/advanced/host-controls) (Chinese)
* [API reference - SMeetingEngine](/zh/meeting/swift/api-reference/SMeetingEngine) (Chinese)
* [Events](/zh/meeting/swift/events) (Chinese)