fix(modal): persist modal through configuration changes (#9533)

packages/core/ui/button/index.ios.ts

@@ -1,10 +1,11 @@
 import { ControlStateChangeListener } from '../core/control-state-change';
 import { ButtonBase } from './button-common';
 import { View, PseudoClassHandler } from '../core/view';
-import { borderTopWidthProperty, borderRightWidthProperty, borderBottomWidthProperty, borderLeftWidthProperty, paddingLeftProperty, paddingTopProperty, paddingRightProperty, paddingBottomProperty } from '../styling/style-properties';
+import { backgroundColorProperty, borderTopWidthProperty, borderRightWidthProperty, borderBottomWidthProperty, borderLeftWidthProperty, paddingLeftProperty, paddingTopProperty, paddingRightProperty, paddingBottomProperty } from '../styling/style-properties';
 import { textAlignmentProperty, whiteSpaceProperty } from '../text-base';
 import { layout } from '../../utils';
 import { CoreTypes } from '../../core-types';
+import { Color } from '../../color';
 
 export * from './button-common';
 
@@ -56,6 +57,14 @@ export class Button extends ButtonBase {
 		}
 	}
 
+	[backgroundColorProperty.getDefault](): UIColor {
+		return this.nativeViewProtected.backgroundColor;
+	}
+
+	[backgroundColorProperty.setNative](value: UIColor | Color) {
+		this.nativeViewProtected.backgroundColor = value instanceof Color ? value.ios : value;
+	}
+
 	[borderTopWidthProperty.getDefault](): CoreTypes.LengthType {
 		return {
 			value: this.nativeViewProtected.contentEdgeInsets.top,

packages/core/ui/core/view/index.android.ts

@@ -161,6 +161,7 @@ function initializeDialogFragment() {
 		private _cancelable: boolean;
 		private _shownCallback: () => void;
 		private _dismissCallback: () => void;
+		private activity: WeakRef<android.app.Activity>;
 
 		constructor() {
 			super();
@@ -215,6 +216,7 @@ function initializeDialogFragment() {
 
 		public onCreateView(inflater: android.view.LayoutInflater, container: android.view.ViewGroup, savedInstanceState: android.os.Bundle): android.view.View {
 			const owner = this.owner;
+			this.activity = new WeakRef(this.getActivity());
 			owner._setupAsRootView(this.getActivity());
 			owner._isAddedToNativeVisualTree = true;
 
@@ -252,7 +254,8 @@ function initializeDialogFragment() {
 		public onDismiss(dialog: android.content.DialogInterface): void {
 			super.onDismiss(dialog);
 			const manager = this.getFragmentManager();
-			if (manager) {
+			const activity = this.activity?.get();
+			if (manager && !activity?.isChangingConfigurations()) {
 				removeModal(this.owner._domId);
 				this._dismissCallback();
 			}
@@ -266,6 +269,10 @@ function initializeDialogFragment() {
 		public onDestroy(): void {
 			super.onDestroy();
 			const owner = this.owner;
+			const activity = this.activity?.get();
+			if (!activity?.isChangingConfigurations()) {
+				this.activity = null;
+			}
 
 			if (owner) {
 				// Android calls onDestroy before onDismiss.

packages/core/ui/frame/index.android.ts

@@ -1189,12 +1189,18 @@ class ActivityCallbacksImplementation implements AndroidActivityCallbacks {
 				rootView._tearDownUI(true);
 			}
 
-			const exitArgs = {
-				eventName: application.exitEvent,
-				object: application.android,
-				android: activity,
-			};
-			application.notify(exitArgs);
+			// this may happen when the user changes the system theme
+			// In such case, isFinishing() is false (and isChangingConfigurations is true), and the app will start again (onCreate) with a savedInstanceState
+			// as a result, launchEvent will never be called
+			// possible alternative: always fire launchEvent and exitEvent, but pass extra flags to make it clear what kind of launch/destroy is happening
+			if (activity.isFinishing()) {
+				const exitArgs = {
+					eventName: application.exitEvent,
+					object: application.android,
+					android: activity,
+				};
+				application.notify(exitArgs);
+			}
 		} finally {
 			superFunc.call(activity);
 		}

packages/core/ui/frame/index.ios.ts

@@ -404,13 +404,13 @@ class UINavigationControllerImpl extends UINavigationController {
 	}
 
 	get owner(): Frame {
-		return this._owner.get();
+		return this._owner.get?.();
 	}
 
 	@profile
 	public viewWillAppear(animated: boolean): void {
 		super.viewWillAppear(animated);
-		const owner = this._owner.get();
+		const owner = this._owner.get?.();
 		if (owner && !owner.isLoaded && !owner.parent) {
 			owner.callLoaded();
 		}
@@ -419,7 +419,7 @@ class UINavigationControllerImpl extends UINavigationController {
 	@profile
 	public viewDidDisappear(animated: boolean): void {
 		super.viewDidDisappear(animated);
-		const owner = this._owner?.get();
+		const owner = this._owner?.get?.();
 		if (owner && owner.isLoaded && !owner.parent && !this.presentedViewController) {
 			owner.callUnloaded();
 			owner._tearDownUI(true);
@@ -543,7 +543,7 @@ class UINavigationControllerImpl extends UINavigationController {
 		super.traitCollectionDidChange(previousTraitCollection);
 
 		if (majorVersion >= 13) {
-			const owner = this._owner.get();
+			const owner = this._owner.get?.();
 			if (owner && this.traitCollection.hasDifferentColorAppearanceComparedToTraitCollection && this.traitCollection.hasDifferentColorAppearanceComparedToTraitCollection(previousTraitCollection)) {
 				owner.notify({
 					eventName: IOSHelper.traitCollectionColorAppearanceChangedEvent,