[fix] make mobile landscape locking opt-in

apps/ios/CrossDeskMobile/ContentView.swift

@@ -840,9 +840,11 @@ private struct ServerSettingsView: View {
                 .pickerStyle(.segmented)
             }
             Section {
-                Toggle("连接后自动横屏", isOn: $session.autoLandscape)
+                Toggle("连接建立后锁定横屏", isOn: $session.autoLandscape)
             } header: {
                 Text("屏幕方向")
+            } footer: {
+                Text("默认关闭。开启后，iPhone 连接时进入并保持横屏；关闭时跟随设备方向。iPad 不受影响。")
             }
             Section {
                 DisclosureGroup(isExpanded: $serverConfigurationExpanded) {

apps/ios/CrossDeskMobile/CrossDeskMobileApp.swift

@@ -15,79 +15,38 @@ final class CrossDeskAppDelegate: NSObject, UIApplicationDelegate {
 @MainActor
 enum AppOrientation {
     nonisolated static let autoLandscapeKey = "crossdesk.mobile.auto-landscape"
-    private static var sessionActive = false
-    private static var waitingForLandscape = false
-    private static var deviceObserver: NSObjectProtocol?
+    private static var sessionOrientations: UIInterfaceOrientationMask?
 
     nonisolated static func beginSession(autoLandscape: Bool) {
         DispatchQueue.main.async { beginSessionOnMain(autoLandscape: autoLandscape) }
     }
 
     private static func beginSessionOnMain(autoLandscape: Bool) {
-        // Repeated transport-ready callbacks must not lock an existing session again.
-        guard !sessionActive else { return }
-        sessionActive = true
-        waitingForLandscape = autoLandscape && UIDevice.current.userInterfaceIdiom == .phone
-        if waitingForLandscape {
-            CrossDeskAppDelegate.supportedOrientations = .landscape
-            resumeObserving()
-        } else {
-            apply(to: .allButUpsideDown)
-        }
+        // Preserve the selected policy through repeated transport-ready callbacks.
+        guard sessionOrientations == nil else { return }
+        let orientations: UIInterfaceOrientationMask = autoLandscape ? .landscape : .allButUpsideDown
+        sessionOrientations = orientations
+        apply(to: orientations)
     }
 
     nonisolated static func endSession() {
         DispatchQueue.main.async {
-            sessionActive = false
-            waitingForLandscape = false
-            stopObserving()
+            sessionOrientations = nil
             apply(to: .portrait)
         }
     }
 
     nonisolated static func resume() {
-        DispatchQueue.main.async { resumeObserving() }
-    }
-
-    private static func resumeObserving() {
-        guard sessionActive, waitingForLandscape, deviceObserver == nil,
-              UIApplication.shared.applicationState == .active else { return }
-        apply(to: .landscape)
-        deviceObserver = NotificationCenter.default.addObserver(
-            forName: UIDevice.orientationDidChangeNotification, object: nil, queue: .main
-        ) { _ in
-            MainActor.assumeIsolated { deviceDidRotate() }
+        DispatchQueue.main.async {
+            apply(to: sessionOrientations ?? .portrait)
         }
-        UIDevice.current.beginGeneratingDeviceOrientationNotifications()
-        deviceDidRotate()
-    }
-
-    nonisolated static func suspend() {
-        DispatchQueue.main.async { stopObserving() }
-    }
-
-    private static func stopObserving() {
-        guard let observer = deviceObserver else { return }
-        NotificationCenter.default.removeObserver(observer)
-        deviceObserver = nil
-        UIDevice.current.endGeneratingDeviceOrientationNotifications()
-    }
-
-    private static func deviceDidRotate() {
-        // UIDevice reports physical posture; window geometry also changes when
-        // we request landscape and must never release the initial lock itself.
-        guard sessionActive, waitingForLandscape, deviceObserver != nil,
-              UIApplication.shared.applicationState == .active,
-              UIDevice.current.orientation.isLandscape else { return }
-        waitingForLandscape = false
-        stopObserving()
-        apply(to: .allButUpsideDown)
     }
 
     private static func apply(to orientations: UIInterfaceOrientationMask) {
         // iPad keeps every orientation available, including in resizable windows.
         guard UIDevice.current.userInterfaceIdiom != .pad else { return }
         CrossDeskAppDelegate.supportedOrientations = orientations
+        guard UIApplication.shared.applicationState == .active else { return }
         for case let scene as UIWindowScene in UIApplication.shared.connectedScenes {
             scene.windows.forEach {
                 $0.rootViewController?.setNeedsUpdateOfSupportedInterfaceOrientations()

apps/ios/CrossDeskMobile/RemoteSessionModel.swift

@@ -312,7 +312,7 @@ final class RemoteSessionModel: NSObject, ObservableObject, CrossDeskRTCBridgeDe
     @Published var videoAdaptationPolicy = VideoAdaptationPolicy.saved {
         didSet { videoAdaptationPolicy.save() }
     }
-    @Published var autoLandscape = UserDefaults.standard.object(forKey: AppOrientation.autoLandscapeKey) as? Bool ?? true {
+    @Published var autoLandscape = UserDefaults.standard.object(forKey: AppOrientation.autoLandscapeKey) as? Bool ?? false {
         didSet { UserDefaults.standard.set(autoLandscape, forKey: AppOrientation.autoLandscapeKey) }
     }
     @Published private(set) var videoSettings = RemoteVideoSettingsState()
@@ -457,7 +457,6 @@ final class RemoteSessionModel: NSObject, ObservableObject, CrossDeskRTCBridgeDe
 
     func applicationDidEnterBackground() {
         appIsActive = false
-        AppOrientation.suspend()
         appUpdates.setEnabled(false)
         privacyNotice.didEnterBackground()
         suspendVideoForBackground()

apps/ios/README.md

@@ -214,14 +214,13 @@ the available space. Settings and reading pages are limited to 720 points.
 Resizing preserves the connection fields and active session. iPhone retains its
 portrait home screen and two-column recent-connection grid.
 
-On iPhone, Settings → Screen orientation (屏幕方向) → Landscape after connecting
-(连接后自动横屏) is enabled by default and saved locally. A new session starts in
-landscape and keeps that orientation until the phone is physically held sideways;
-it then resumes the existing device-following policy for the rest of the session.
-Portrait, flat and unknown device poses do not release the initial landscape hold.
-Turning the option off keeps the existing rotation behavior. Leaving the session
-restores portrait; foregrounding the same session does not reapply a released hold.
-iPad orientation and multitasking are unaffected.
+On iPhone, Settings → Screen orientation (屏幕方向) → Lock landscape after connecting
+(连接建立后锁定横屏) is disabled by default and saved locally. When enabled, the session
+enters and stays in landscape; when disabled, it follows the device orientation.
+Leaving the session restores portrait, and returning to a background session keeps
+that session's orientation setting. The physical-device monitoring that released
+the initial landscape hold has been removed. iPad orientation and multitasking
+are unaffected.
 
 ## System keyboard and remote text