From e6beb1d8165f8c84b8a8f4632d10fed31c1ad68a Mon Sep 17 00:00:00 2001
From: Dimitris-Rafail Katsampas <katsampasdr@gmail.com>
Date: Wed, 29 Jan 2025 21:26:59 +0200
Subject: [PATCH] fix(core): pseudo-class handlers failing to unsubscribe
 listeners (#10680)

---
 packages/core/ui/button/index.android.ts      |  1 +
 packages/core/ui/button/index.ios.ts          | 32 ++++++++++++-------
 .../ui/core/control-state-change/index.ios.ts |  9 +++---
 packages/core/ui/core/view/view-common.ts     | 22 +++++++------
 .../editable-text-base-common.ts              | 16 +++++++---
 packages/core/ui/styling/style-scope.ts       |  4 +--
 6 files changed, 51 insertions(+), 33 deletions(-)

diff --git a/packages/core/ui/button/index.android.ts b/packages/core/ui/button/index.android.ts
index 2660d8c43..09aa8ba98 100644
--- a/packages/core/ui/button/index.android.ts
+++ b/packages/core/ui/button/index.android.ts
@@ -103,6 +103,7 @@ export class Button extends ButtonBase {
 			this.on(GestureTypes[GestureTypes.touch], onButtonStateChange);
 		} else {
 			this.off(GestureTypes[GestureTypes.touch], onButtonStateChange);
+			this._removeVisualState('highlighted');
 		}
 	}
 
diff --git a/packages/core/ui/button/index.ios.ts b/packages/core/ui/button/index.ios.ts
index a5f87a780..753b1e136 100644
--- a/packages/core/ui/button/index.ios.ts
+++ b/packages/core/ui/button/index.ios.ts
@@ -29,6 +29,12 @@ export class Button extends ButtonBase {
 
 	public disposeNativeView(): void {
 		this._tapHandler = null;
+
+		if (this._stateChangedHandler) {
+			this._stateChangedHandler.stop();
+			this._stateChangedHandler = null;
+		}
+
 		super.disposeNativeView();
 	}
 
@@ -37,28 +43,32 @@ export class Button extends ButtonBase {
 		return this.nativeViewProtected;
 	}
 
-	public onUnloaded() {
-		super.onUnloaded();
-		if (this._stateChangedHandler) {
-			this._stateChangedHandler.stop();
-		}
-	}
-
 	@PseudoClassHandler('normal', 'highlighted', 'pressed', 'active')
 	_updateButtonStateChangeHandler(subscribe: boolean) {
 		if (subscribe) {
 			if (!this._stateChangedHandler) {
+				const viewRef = new WeakRef<Button>(this);
+
 				this._stateChangedHandler = new ControlStateChangeListener(this.nativeViewProtected, observableVisualStates, (state: string, add: boolean) => {
-					if (add) {
-						this._addVisualState(state);
-					} else {
-						this._removeVisualState(state);
+					const view = viewRef?.deref?.();
+
+					if (view) {
+						if (add) {
+							view._addVisualState(state);
+						} else {
+							view._removeVisualState(state);
+						}
 					}
 				});
 			}
 			this._stateChangedHandler.start();
 		} else {
 			this._stateChangedHandler.stop();
+
+			// Remove any possible pseudo-class leftovers
+			for (const state of observableVisualStates) {
+				this._removeVisualState(state);
+			}
 		}
 	}
 
diff --git a/packages/core/ui/core/control-state-change/index.ios.ts b/packages/core/ui/core/control-state-change/index.ios.ts
index d03a85b44..a6db87661 100644
--- a/packages/core/ui/core/control-state-change/index.ios.ts
+++ b/packages/core/ui/core/control-state-change/index.ios.ts
@@ -2,9 +2,9 @@
 
 @NativeClass
 class ObserverClass extends NSObject {
-	public callback: WeakRef<ControlStateChangeListenerCallback>;
+	public callback: ControlStateChangeListenerCallback;
 
-	public static initWithCallback(callback: WeakRef<ControlStateChangeListenerCallback>): ObserverClass {
+	public static initWithCallback(callback: ControlStateChangeListenerCallback): ObserverClass {
 		const observer = <ObserverClass>ObserverClass.alloc().init();
 		observer.callback = callback;
 
@@ -12,8 +12,7 @@ class ObserverClass extends NSObject {
 	}
 
 	public observeValueForKeyPathOfObjectChangeContext(path: string, object: UIControl) {
-		const callback = this.callback?.deref();
-
+		const callback = this.callback;
 		if (callback) {
 			callback(path, object[path]);
 		}
@@ -30,7 +29,7 @@ export class ControlStateChangeListener implements ControlStateChangeListenerDef
 	constructor(control: UIControl, states: string[], callback: ControlStateChangeListenerCallback) {
 		this._control = control;
 		this._states = states;
-		this._observer = ObserverClass.initWithCallback(new WeakRef(callback));
+		this._observer = ObserverClass.initWithCallback(callback);
 	}
 
 	public start() {
diff --git a/packages/core/ui/core/view/view-common.ts b/packages/core/ui/core/view/view-common.ts
index bc1338b03..dec605166 100644
--- a/packages/core/ui/core/view/view-common.ts
+++ b/packages/core/ui/core/view/view-common.ts
@@ -53,19 +53,21 @@ export function viewMatchesModuleContext(view: ViewDefinition, context: ModuleCo
 
 export function PseudoClassHandler(...pseudoClasses: string[]): MethodDecorator {
 	const stateEventNames = pseudoClasses.map((s) => ':' + s);
-	const listeners = Symbol('listeners');
 
-	return <T>(target: Object, propertyKey: string | symbol, descriptor: TypedPropertyDescriptor<T>) => {
-		function update(change: number) {
-			const prev = this[listeners] || 0;
-			const next = prev + change;
-			if (prev <= 0 && next > 0) {
-				this[propertyKey](true);
-			} else if (prev > 0 && next <= 0) {
-				this[propertyKey](false);
+	return <T>(target: Object, propertyKey: string, descriptor: TypedPropertyDescriptor<T>) => {
+		// This will help keep track of pseudo-class subscription changes
+		const subscribeKey = Symbol(propertyKey + '_flag');
+
+		function onSubscribe(subscribe: boolean) {
+			if (subscribe != !!this[subscribeKey]) {
+				this[subscribeKey] = subscribe;
+				this[propertyKey](subscribe);
 			}
 		}
-		stateEventNames.forEach((s) => (target[s] = update));
+
+		for (const eventName of stateEventNames) {
+			target[eventName] = onSubscribe;
+		}
 	};
 }
 
diff --git a/packages/core/ui/editable-text-base/editable-text-base-common.ts b/packages/core/ui/editable-text-base/editable-text-base-common.ts
index 5ed2fee13..166774899 100644
--- a/packages/core/ui/editable-text-base/editable-text-base-common.ts
+++ b/packages/core/ui/editable-text-base/editable-text-base-common.ts
@@ -34,19 +34,25 @@ export abstract class EditableTextBase extends TextBase implements EditableTextB
 	public autocorrect: boolean;
 	public hint: string;
 	public maxLength: number;
+	public placeholderColor: Color;
 	public valueFormatter: (value: string) => string;
 
 	public abstract dismissSoftInput();
 	public abstract _setInputType(inputType: number): void;
 	public abstract setSelection(start: number, stop?: number);
-	placeholderColor: Color;
 
 	@PseudoClassHandler('focus', 'blur')
-	_updateTextBaseFocusStateHandler(subscribe) {
-		const method = subscribe ? 'on' : 'off';
+	_updateTextBaseFocusStateHandler(subscribe: boolean) {
+		if (subscribe) {
+			this.on('focus', focusChangeHandler);
+			this.on('blur', focusChangeHandler);
+		} else {
+			this.off('focus', focusChangeHandler);
+			this.off('blur', focusChangeHandler);
 
-		this[method]('focus', focusChangeHandler);
-		this[method]('blur', focusChangeHandler);
+			this._removeVisualState('focus');
+			this._removeVisualState('blur');
+		}
 	}
 }
 
diff --git a/packages/core/ui/styling/style-scope.ts b/packages/core/ui/styling/style-scope.ts
index e8dcd5ed8..08eaecd39 100644
--- a/packages/core/ui/styling/style-scope.ts
+++ b/packages/core/ui/styling/style-scope.ts
@@ -792,7 +792,7 @@ export class CssState {
 					const eventName = ':' + pseudoClass;
 					view.addEventListener(':' + pseudoClass, this._onDynamicStateChangeHandler);
 					if (view[eventName]) {
-						view[eventName](+1);
+						view[eventName](true);
 					}
 				});
 			}
@@ -812,7 +812,7 @@ export class CssState {
 					const eventName = ':' + pseudoClass;
 					view.removeEventListener(eventName, this._onDynamicStateChangeHandler);
 					if (view[eventName]) {
-						view[eventName](-1);
+						view[eventName](false);
 					}
 				});
 			}