feat(ios): handle scene delegates with soft reboot

NathanWalker · NathanWalker · commit 6c1479b255b8 · 2026-07-20T13:52:31.000-07:00
diff --git a/packages/core/application/application.ios.ts b/packages/core/application/application.ios.ts
@@ -127,6 +127,16 @@ function supportsMultipleScenes(): boolean {
 	return UIApplication.sharedApplication?.supportsMultipleScenes;
 }
 
+/**
+ * Number of times the JS runtime has been soft-rebooted in this process via
+ * NativeScriptRuntime.reloadApplication / restartWithConfig. 0 on first boot.
+ * Provided as a global by the iOS runtime (v9+); older runtimes report 0.
+ */
+function getRuntimeReloadCount(): number {
+	const runtime = (globalThis as any).NativeScriptRuntime;
+	return runtime && typeof runtime.reloadCount === 'number' ? runtime.reloadCount : 0;
+}
+
 @NativeClass
 class Responder extends UIResponder implements UIApplicationDelegate {
 	get window(): UIWindow {
@@ -269,6 +279,13 @@ export class iOSApplication extends ApplicationCommon implements IiOSApplication
 
 	private _notificationObservers: NotificationObserver[] = [];
 
+	// Strong references to delegates recreated after an in-process soft reboot
+	// (NativeScriptRuntime.reloadApplication). UIApplication.delegate is an
+	// `assign` property and UIScene keeps its own reference to the delegate we
+	// replace, so without these the fresh instances would be deallocated.
+	private _softRebootAppDelegate: UIApplicationDelegate;
+	private _softRebootSceneDelegates = new Map<UIScene, UIWindowSceneDelegate>();
+
 	displayedOnce = false;
 	displayedLinkTarget: CADisplayLinkTarget;
 	displayedLink: CADisplayLink;
@@ -323,6 +340,8 @@ export class iOSApplication extends ApplicationCommon implements IiOSApplication
 	}
 
 	private runAsEmbeddedApp() {
+		this._reattachNativeDelegatesAfterSoftReboot();
+
 		// TODO: this rootView should be held alive until rootController dismissViewController is called.
 		const rootView = this.createRootView(this._rootView, true);
 		if (!rootView) {
@@ -357,6 +376,13 @@ export class iOSApplication extends ApplicationCommon implements IiOSApplication
 				window = UIWindow.alloc().initWithWindowScene(targetScene);
 				this._setWindowForScene(window, targetScene);
 				this._setupWindowForScene?.(window, targetScene);
+
+				// If the scene's delegate was recreated after a soft reboot, point it
+				// at the new window so `scene.delegate.window` queries resolve.
+				const freshSceneDelegate = this._softRebootSceneDelegates.get(targetScene);
+				if (freshSceneDelegate) {
+					freshSceneDelegate.window = window;
+				}
 			}
 		}
 
@@ -367,12 +393,12 @@ export class iOSApplication extends ApplicationCommon implements IiOSApplication
 		// May be null on a freshly recreated window — expected; the replace-root
 		// path below sets it. Only the embedder path needs an existing controller.
 		const rootController = window.rootViewController;
-        const embedderDelegate = NativeScriptEmbedder.sharedInstance().delegate;
+		const embedderDelegate = NativeScriptEmbedder.sharedInstance().delegate;
 
-        // Embed into host app requires an existing root view controller
-        if (embedderDelegate && !rootController) {
-            return;
-        }
+		// Embed into host app requires an existing root view controller
+		if (embedderDelegate && !rootController) {
+			return;
+		}
 
 		const controller = this.getViewController(rootView);
 
@@ -406,6 +432,67 @@ export class iOSApplication extends ApplicationCommon implements IiOSApplication
 		this.notifyAppStarted();
 	}
 
+	/**
+	 * After an in-process soft reboot (NativeScriptRuntime.reloadApplication /
+	 * restartWithConfig), the Objective-C delegate classes created by the
+	 * previous JS isolate still exist and UIKit keeps dispatching to their
+	 * now-inert instances: their method callbacks bail out because the isolate
+	 * that implemented them is gone. Notification-center observers are
+	 * re-registered by the new isolate, but delegate-based dispatch (custom
+	 * UIApplicationDelegate methods like push-token/openURL callbacks, and the
+	 * UIScene delegates used by scene-lifecycle apps) stays pinned to the old
+	 * bundle. Recreate those delegates from this bundle's classes and re-point
+	 * UIKit at them.
+	 */
+	private _reattachNativeDelegatesAfterSoftReboot(): void {
+		if (getRuntimeReloadCount() <= 0) {
+			// First boot: UIApplicationMain (or the host app) set up delegates.
+			return;
+		}
+
+		if (isEmbedded()) {
+			// The host app owns the UIApplication delegate; never touch it.
+			return;
+		}
+
+		const app = UIApplication.sharedApplication;
+		if (!app) {
+			return;
+		}
+
+		// Fresh application delegate from the new bundle. Assigning `delegate`
+		// does not retain (unlike the UIApplicationMain launch path), so keep a
+		// strong reference ourselves.
+		this.delegate ??= Responder as any;
+		const freshDelegate = (<any>this.delegate).new() as UIApplicationDelegate;
+		this._softRebootAppDelegate = freshDelegate;
+		app.delegate = freshDelegate;
+
+		// Re-point already-connected scenes at fresh scene delegates so scene
+		// lifecycle and user-implemented scene delegate methods (shortcuts,
+		// openURLContexts, userActivity continuation, etc.) reach this isolate.
+		// Newly connecting scenes are covered by the fresh application delegate's
+		// applicationConfigurationForConnectingSceneSessionOptions, which returns
+		// this bundle's SceneDelegate class.
+		if (this.supportsScenes()) {
+			this._softRebootSceneDelegates.clear();
+			const scenes = app.connectedScenes?.allObjects;
+			for (let i = 0; scenes && i < scenes.count; i++) {
+				const scene = scenes.objectAtIndex(i);
+				if (!(scene instanceof UIWindowScene)) {
+					continue;
+				}
+				const freshSceneDelegate = SceneDelegate.new() as UIWindowSceneDelegate;
+				scene.delegate = freshSceneDelegate;
+				this._softRebootSceneDelegates.set(scene, freshSceneDelegate);
+			}
+		}
+
+		if (Trace.isEnabled()) {
+			Trace.write(`Reattached application delegate${this._softRebootSceneDelegates.size ? ` and ${this._softRebootSceneDelegates.size} scene delegate(s)` : ''} after soft reboot (reloadCount: ${getRuntimeReloadCount()})`, Trace.categories.NativeLifecycle);
+		}
+	}
+
 	private getViewController(rootView: View): UIViewController {
 		let viewController: UIViewController = rootView.viewController || rootView.ios;
 
