perf(ios): UIImage memory leaks (#9783)

apps/toolbox/src/pages/a11y.ts

@@ -17,6 +17,7 @@ export class AccessibilityModel extends Observable {
 	accessibilityLiveRegions = AccessibilityLiveRegion;
 	accessibilityRole = AccessibilityRole;
 	accessibilityState = AccessibilityState;
+	largeImageSrc = 'https://i.picsum.photos/id/669/5000/5000.jpg?hmac=VlpchW0ODhflKm0SKOYQrc8qysLWbqKmDS1MGT9apAc';
 
 	constructor() {
 		super();
@@ -26,6 +27,11 @@ export class AccessibilityModel extends Observable {
 		const checked = (args.object as Switch).checked;
 		console.log(checked);
 		this.set('switchCheckedText', `${this.labelText} ${checked}`);
+
+		// prettier-ignore
+		this.set('largeImageSrc', checked ? 
+			'https://i.picsum.photos/id/669/5000/5000.jpg?hmac=VlpchW0ODhflKm0SKOYQrc8qysLWbqKmDS1MGT9apAc' : 
+			'https://i.picsum.photos/id/684/5000/5000.jpg?hmac=loiXO_OQ-y86XY_hc7p3qJdY39fSd9CuDM0iA_--P4Q');
 	}
 
 	openModal() {

apps/toolbox/src/pages/a11y.xml

@@ -12,13 +12,16 @@
             
             <Image src="res://icon" width="50" class="view-item a11y" accessibilityLabel="Image with explicit attribute role" accessibilityRole="{{accessibilityRole.Image}}" />
             <Image src="res://icon" width="50" class="view-item a11y a11y-role-image" accessibilityLabel="Image with css defined role" />
+            
+            
+            <Image src="{{ largeImageSrc }}" width="50" class="view-item a11y a11y-role-image" accessibilityLabel="Image with css defined role" />
 
             <Switch checked="true" class="view-item a11y" accessibilityLabel="Switch with attribute state" accessibilityState="{{accessibilityState.Checked}}" checkedChange="{{checkedChange}}" />
             <Switch checked="true" class="view-item a11y a11y-state-checked" accessibilityLabel="Switch with css state" checkedChange="{{checkedChange}}" />
 
-            <TextView hint="TextView" text="{{switchCheckedText}}" class="view-item a11y" accessibilityLabel="TestView with a value" accessibilityLiveRegion="{{accessibilityLiveRegions.Polite}}"/>
-            <TextField hint="TextField" class="view-item a11y" accessibilityLabel="Plain jane TextField" accessibilityHint="Tell us your real name Jane"/>
-            <TextView hint="TextView" class="view-item a11y" accessibilityLabel="Nice TextView" accessibilityHint="Tell us about yourself Jane"/>
+            <TextView hint="TextView" text="{{switchCheckedText}}" class="view-item a11y" accessibilityLabel="TestView with a value" accessibilityLiveRegion="{{accessibilityLiveRegions.Polite}}" />
+            <TextField hint="TextField" class="view-item a11y" accessibilityLabel="Plain jane TextField" accessibilityHint="Tell us your real name Jane" />
+            <TextView hint="TextView" class="view-item a11y" accessibilityLabel="Nice TextView" accessibilityHint="Tell us about yourself Jane" />
             <GridLayout rows="25" columns="*" class="view-item" accessibilityLabel="No can go GridLayout" accessibilityHint="A grid that will not get bigger when increasing accessible text size">
               <Label text="IN-Accessible Grid" class="view-item text-center" />
             </GridLayout>
@@ -28,7 +31,7 @@
               <Label rowSpan="2" col="1" text="Hi" />
             </GridLayout>
             <Button text="Open Modal" class="view-item" tap="{{openModal}}" />
-            <Slider value="10" minValue="0" maxValue="100" class="view-item a11y" accessibilityLabel="Slider" accessibilityHint="A smooth slider" accessibilityValue="10"/>
+            <Slider value="10" minValue="0" maxValue="100" class="view-item a11y" accessibilityLabel="Slider" accessibilityHint="A smooth slider" accessibilityValue="10" />
           </StackLayout>
       </ScrollView>
     </GridLayout>

packages/core/ui/image/image-common.ts

@@ -28,10 +28,16 @@ export abstract class ImageBase extends View implements ImageDefinition {
 		this.style.tintColor = value;
 	}
 
+	public disposeImageSource() {
+		// override in subclass
+	}
+
 	/**
 	 * @internal
 	 */
 	public _createImageSourceFromSrc(value: string | ImageSource | ImageAsset): void {
+		this.disposeImageSource();
+
 		const originalValue = value;
 		const sync = this.loadMode === 'sync';
 		if (typeof value === 'string' || value instanceof String) {

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

@@ -2,7 +2,7 @@ import { ImageBase, stretchProperty, imageSourceProperty, tintColorProperty, src
 import { ImageSource } from '../../image-source';
 import { Color } from '../../color';
 import { Trace } from '../../trace';
-import { layout } from '../../utils';
+import { layout, queueGC } from '../../utils';
 
 export * from './image-common';
 
@@ -24,21 +24,28 @@ export class Image extends ImageBase {
 		this._setNativeClipToBounds();
 	}
 
-	public disposeNativeView(): void {
-		super.disposeNativeView();
+	public disposeImageSource() {
+		if (this.nativeViewProtected?.image === this.imageSource?.ios) {
+			this.nativeViewProtected.image = null;
+		}
 
 		if (this.imageSource?.ios) {
 			this.imageSource.ios = null;
-			// causes crash currently:
-			// release the native UIImage
-			// CFRelease(this.imageSource.ios);
 		}
 
 		this.imageSource = null;
 
+		queueGC();
+	}
+
+	public disposeNativeView(): void {
+		super.disposeNativeView();
+
 		if (this.nativeViewProtected?.image) {
 			this.nativeViewProtected.image = null;
 		}
+
+		this.disposeImageSource();
 	}
 
 	private setTintColor(value: Color) {
@@ -46,15 +53,23 @@ export class Image extends ImageBase {
 			if (value && this.nativeViewProtected.image && !this._templateImageWasCreated) {
 				this.nativeViewProtected.image = this.nativeViewProtected.image.imageWithRenderingMode(UIImageRenderingMode.AlwaysTemplate);
 				this._templateImageWasCreated = true;
+				queueGC();
 			} else if (!value && this.nativeViewProtected.image && this._templateImageWasCreated) {
 				this._templateImageWasCreated = false;
 				this.nativeViewProtected.image = this.nativeViewProtected.image.imageWithRenderingMode(UIImageRenderingMode.Automatic);
+				queueGC();
 			}
 			this.nativeViewProtected.tintColor = value ? value.ios : null;
 		}
 	}
 
 	public _setNativeImage(nativeImage: UIImage) {
+		if (this.nativeViewProtected?.image) {
+			this.nativeViewProtected.image = null;
+
+			queueGC();
+		}
+
 		if (this.nativeViewProtected) {
 			this.nativeViewProtected.image = nativeImage;
 		}
@@ -169,6 +184,10 @@ export class Image extends ImageBase {
 	}
 
 	[imageSourceProperty.setNative](value: ImageSource) {
+		if (value !== this.imageSource) {
+			this.disposeImageSource();
+		}
+
 		this._setNativeImage(value ? value.ios : null);
 	}
 

packages/core/utils/index.d.ts

@@ -187,6 +187,11 @@ export namespace ad {
  */
 export function GC();
 
+/**
+ * An utility function that queues a garbage collection, subseqent calls will be throttled and only one gc will be executed.
+ */
+export function queueGC();
+
 /**
  * Releases the reference to the wrapped native object
  * @param object The Java/Objective-C object to release.

packages/core/utils/utils-common.ts

@@ -3,6 +3,8 @@ import { dispatchToMainThread, isMainThread } from './mainthread-helper';
 import { sanitizeModuleName } from '../ui/builder/module-name-sanitizer';
 import * as layout from './layout-helper';
 
+import { GC } from './index';
+
 export { layout };
 export * from './mainthread-helper';
 export * from './macrotask-scheduler';
@@ -129,3 +131,17 @@ export function mainThreadify(func: Function): (...args: any[]) => void {
 		executeOnMainThread(() => func.apply(this, argsToPass));
 	};
 }
+
+let hasQueuedGC = false;
+export function queueGC() {
+	if (hasQueuedGC) {
+		return;
+	}
+
+	hasQueuedGC = true;
+
+	setTimeout(() => {
+		hasQueuedGC = false;
+		GC();
+	}, 1000);
+}