review-case

name	review-case
description	Structured code review for a case in the APIExample-SwiftUI project. Checks engine lifecycle, SwiftUI state ownership, thread safety, permissions, and API correctness.
compatibility	["Cursor","Kiro","Windsurf","Claude","Copilot"]
license	MIT
metadata	{"author":"APIExample Team","version":"1.0.0","platform":"iOS"}

review-case — APIExample-SwiftUI

Review Dimensions (in priority order)

1. Engine Lifecycle

Check:

• AgoraRtcEngineKit created inside setupRTC() of the RTC class, not in the Entry view
• leaveChannel() + AgoraRtcEngineKit.destroy() called inside onDestroy()
• setupRTC() called from .onAppear, onDestroy() called from .onDisappear
• No engine instance retained beyond the RTC object's lifetime

Correct:

.onAppear { rtc.setupRTC(configs: configs) }
.onDisappear { rtc.onDestroy() }

Wrong:

// Missing onDisappear — engine never destroyed
.onAppear { rtc.setupRTC(configs: configs) }

---

2. SwiftUI State Ownership

Check:

• Main view declares RTC object as @ObservedObject, not @StateObject
• Entry view does not hold a reference to the RTC object
• @Published properties used for state that drives UI updates

Correct:

struct MyCase: View {
    @ObservedObject private var rtc = MyCaseRTC()  // correct
}

Wrong:

struct MyCase: View {
    @StateObject private var rtc = MyCaseRTC()  // wrong — SwiftUI owns lifetime, may outlive view
}

---

3. Thread Safety

All AgoraRtcEngineDelegate callbacks may arrive on a background thread.

Check:

• Every @Published property mutation inside a delegate callback is dispatched to DispatchQueue.main
• No direct SwiftUI state mutation on background thread

Correct:

func rtcEngine(_ engine: AgoraRtcEngineKit, didJoinedOfUid uid: UInt, elapsed: Int) {
    DispatchQueue.main.async {
        self.remoteUid = uid
    }
}

---

4. Permissions

Check:

• Camera/microphone permissions requested before joinChannel()
• joinChannel() called only inside the permission grant callback

---

5. Error Handling

Check:

• Return value of joinChannel() checked
• rtcEngine(_:didOccurError:) implemented and logged
• Token expiry handled if token is used

---

6. Code Conventions

Check:

• RTC class inherits NSObject, conforms to ObservableObject and AgoraRtcEngineDelegate
• Entry view named <ExampleName>Entry, main view named <ExampleName>
• RTC class named <ExampleName>RTC
• configs dictionary used to pass data from Entry to Main
• No SDK calls inside SwiftUI body computed property

---

7. Resource Cleanup

Check:

• Audio files / custom audio tracks stopped in onDestroy()
• External video sources unregistered in onDestroy()
• Media player destroyed if created
• Screen capture stopped if started
• Multi-camera capture stopped if started

---

Review Output Format

[SEVERITY] file/line — issue description
Suggestion: how to fix

Severity levels:

• [CRITICAL] — crash, leak, or incorrect behavior
• [WARNING] — convention violation or subtle bug risk
• [INFO] — style or minor improvement

---

SwiftUI-Specific Checks

• onAppear can fire multiple times (e.g., sheet dismiss, navigation pop/push) — verify setupRTC is idempotent or guarded
• onDisappear fires when the view is covered by another view in a TabView — verify this does not prematurely destroy the engine
• Video rendering views (VideoView / VideoUIView) must be created before setupRTC is called so the canvas can be set up correctly
• [weak self] required in all closures capturing self inside the RTC class to avoid retain cycles