From 08ce45959c46e04f7c1f8f7e2f4478cf53c1341b Mon Sep 17 00:00:00 2001
From: Rossen Hristov <rossen.hristov@telerik.com>
Date: Mon, 20 Apr 2015 09:44:29 +0300
Subject: [PATCH] Fixed the memory leaks in iOS.

---
 apps/cuteness.io/main-page.xml             |  2 +-
 apps/cuteness.io/reddit-item-view-model.ts | 70 ++++++++++------------
 ui/image-cache/image-cache.ios.ts          | 58 +++++++++++++++++-
 ui/image/image-common.ts                   | 19 +++---
 ui/image/image.android.ts                  |  8 ++-
 ui/image/image.d.ts                        |  4 +-
 ui/image/image.ios.ts                      | 18 ++++--
 7 files changed, 120 insertions(+), 59 deletions(-)

diff --git a/apps/cuteness.io/main-page.xml b/apps/cuteness.io/main-page.xml
index 311245c70..e062e9486 100644
--- a/apps/cuteness.io/main-page.xml
+++ b/apps/cuteness.io/main-page.xml
@@ -7,7 +7,7 @@
             <ListView.itemTemplate>
               <!-- Binding in template property of an component will use the bindingContext provided by the component. -->
               <GridLayout columns="auto, *, auto" rows="auto, 25">
-                <Image imageSource="{{ thumbnailImageSource || defaultThumbnailImageSource }}" cssClass="thumbnail" rowSpan="2"/>
+                <Image src="{{ thumbnailImage }}" cssClass="thumbnail" rowSpan="2"/>
                 <Label text="{{ title || 'Downloading...' }}" textWrap="true" cssClass="title" col="1" colSpan="2" minHeight="50" />
                 <Label text="{{ author ? 'by ' + author : '' }}" cssClass="author" col="1" row="1" />
                 <Label text="{{ num_comments ? num_comments + ' comments' : '' }}" cssClass="comments" col="2" row="1" />
diff --git a/apps/cuteness.io/reddit-item-view-model.ts b/apps/cuteness.io/reddit-item-view-model.ts
index 3c36bc9ed..a4b5af2c4 100644
--- a/apps/cuteness.io/reddit-item-view-model.ts
+++ b/apps/cuteness.io/reddit-item-view-model.ts
@@ -8,7 +8,7 @@ var firstThumbnailImageSource = imageSource.fromFile("~/res/first-image.png");
 var defaultImageSource = imageSource.fromFile("~/res/reddit-logo-transparent.png");
 
 var ISLOADING = "isLoading";
-var THUMBNAIL_IMAGE_SOURCE = "thumbnailImageSource";
+var THUMBNAIL_IMAGE = "thumbnailImage";
 var IMAGE_SOURCE = "imageSource";
 
 export class RedditViewModel extends observable.Observable {
@@ -42,45 +42,39 @@ export class RedditViewModel extends observable.Observable {
         }
     }
 
-    private _thumbnailImageSource: imageSource.ImageSource;
-    get thumbnailImageSource(): imageSource.ImageSource {
-        if (this._source) {
-            if (this._source.title === "reddit 101") {
-                this._thumbnailImageSource = firstThumbnailImageSource;
-            } else if (redditAppViewModel.cache) {
-                var url = this._source.thumbnail;
-
-                var imgSource: imageSource.ImageSource;
-                var image = redditAppViewModel.cache.get(url);
-                if (image) {
-                    imgSource = imageSource.fromNativeSource(image);
-                }
-
-                if (imgSource) {
-                    this._thumbnailImageSource = imgSource;
-                }
-                else if (_isValidImageUrl(url)) {
-                    this.isLoading = true;
-
-                    redditAppViewModel.cache.push({
-                        key: url,
-                        url: url,
-                        completed: (image: any, key: string) => {
-                            if (url === key) {
-                                this.isLoading = false;
-                                var imgSource = imageSource.fromNativeSource(image);
-                                this._thumbnailImageSource = imgSource;
-                                this.notify({ object: this, eventName: observable.knownEvents.propertyChange, propertyName: THUMBNAIL_IMAGE_SOURCE, value: imgSource });
-                            }
-                        }
-                    });
-                } else {
-                    this._thumbnailImageSource = redditAppViewModel.defaultNoThumbnailImageSource;
-                }
-            }
+    get thumbnailImage(): imageSource.ImageSource {
+        if (!this._source) {
+            return redditAppViewModel.defaultThumbnailImageSource;
         }
 
-        return this._thumbnailImageSource || redditAppViewModel.defaultThumbnailImageSource;
+        if (this._source.title === "reddit 101") {
+            return firstThumbnailImageSource;
+        }
+
+        var url = this._source.thumbnail;
+        
+        if (!_isValidImageUrl(url)) { 
+            return redditAppViewModel.defaultNoThumbnailImageSource
+        }
+
+        var image = redditAppViewModel.cache.get(url);
+        if (image) {
+            return image;
+        }
+
+        this.isLoading = true;
+        redditAppViewModel.cache.push({
+            key: url,
+            url: url,
+            completed: (image: any, key: string) => {
+                if (url === key) {
+                    this.isLoading = false;
+                    this.notify({ object: this, eventName: observable.knownEvents.propertyChange, propertyName: THUMBNAIL_IMAGE, value: image });
+                }
+            }
+        });
+
+        return redditAppViewModel.defaultThumbnailImageSource;
     }
 
     get imageSource(): imageSource.ImageSource {
diff --git a/ui/image-cache/image-cache.ios.ts b/ui/image-cache/image-cache.ios.ts
index e9dd60330..04c8df8e7 100644
--- a/ui/image-cache/image-cache.ios.ts
+++ b/ui/image-cache/image-cache.ios.ts
@@ -1,22 +1,77 @@
 import common = require("ui/image-cache/image-cache-common");
 import httpRequest = require("http/http-request");
+import utils = require("utils/utils");
+import trace = require("trace");
 
 module.exports.knownEvents = common.knownEvents;
 
+//class NSCacheDelegateImpl extends NSObject implements NSCacheDelegate {
+//    public static ObjCProtocols = [NSCacheDelegate];
+
+//    static new(): NSCacheDelegateImpl {
+//        return <NSCacheDelegateImpl>super.new();
+//    }
+
+//    public cacheWillEvictObject(cache: NSCache, obj: any): void {
+//        trace.write("NSCacheDelegateImpl.cacheWillEvictObject(" + obj + ");", trace.categories.Debug);
+//    }
+//}
+
+class MemmoryWarningHandler extends NSObject {
+    static new(): MemmoryWarningHandler {
+        return <MemmoryWarningHandler>super.new();
+    }
+
+    private _cache: NSCache;
+
+    public initWithCache(cache: NSCache): MemmoryWarningHandler {
+        this._cache = cache;
+        
+        NSNotificationCenter.defaultCenter().addObserverSelectorNameObject(this, "clearCache", "UIApplicationDidReceiveMemoryWarningNotification", null);
+        trace.write("[MemmoryWarningHandler] Added low memory observer.", trace.categories.Debug);
+        
+        return this;
+    }
+
+    public dealloc(): void {
+        NSNotificationCenter.defaultCenter().removeObserverNameObject(this, "UIApplicationDidReceiveMemoryWarningNotification", null);
+        trace.write("[MemmoryWarningHandler] Removed low memory observer.", trace.categories.Debug);
+        super.dealloc();
+    }
+
+    public clearCache(): void {
+        trace.write("[MemmoryWarningHandler] Clearing Image Cache.", trace.categories.Debug);
+        this._cache.removeAllObjects();
+        utils.GC();
+    }
+
+    public static ObjCExposedMethods = {
+        "clearCache": { returns: interop.types.void, params: [] }
+    };
+}
+
+
 export class Cache extends common.Cache {
     private _cache: NSCache;
+    //private _delegate: NSCacheDelegate;
+    private _memoryWarningHandler: MemmoryWarningHandler;
 
     constructor() {
         super();
 
         this._cache = new NSCache();
+        
+        //this._delegate = NSCacheDelegateImpl.new();
+        //this._cache.delegate = this._delegate;
+
+        this._memoryWarningHandler = MemmoryWarningHandler.new().initWithCache(this._cache);
     }
 
     public _downloadCore(request: common.DownloadRequest) {
         var that = this;
         httpRequest.request({ url: request.url, method: "GET" })
             .then(response => {
-                var image = UIImage.imageWithData(response.content.raw);
+                var image = UIImage.alloc().initWithData(response.content.raw);
                 that._onDownloadCompleted(request.key, image);
             });
     }
@@ -35,5 +90,6 @@ export class Cache extends common.Cache {
 
     public clear() {
         this._cache.removeAllObjects();
+        utils.GC();
     }
 }
\ No newline at end of file
diff --git a/ui/image/image-common.ts b/ui/image/image-common.ts
index 33ed43351..dad61cd07 100644
--- a/ui/image/image-common.ts
+++ b/ui/image/image-common.ts
@@ -15,15 +15,11 @@ var IMAGE = "Image";
 var ISLOADING = "isLoading";
 var STRETCH = "stretch";
 
-function isValidSrc(src: any): boolean {
-    return types.isString(src);
-}
-
 function onSrcPropertyChanged(data: dependencyObservable.PropertyChangeData) {
     var image = <Image>data.object;
     var value = data.newValue;
 
-    if (isValidSrc(value)) {
+    if (types.isString(value)) {
         value = value.trim();
         image.imageSource = null;
         image["_url"] = value;
@@ -46,6 +42,9 @@ function onSrcPropertyChanged(data: dependencyObservable.PropertyChangeData) {
         // Support binding the iamgeSource trough the src propoerty
         image.imageSource = value;
     }
+    else {
+        image._setNativeImage(value);
+    }
 }
 
 export class Image extends view.View implements definition.Image {
@@ -54,7 +53,7 @@ export class Image extends view.View implements definition.Image {
         SRC,
         IMAGE,
         new proxy.PropertyMetadata(
-            "",
+            undefined,
             dependencyObservable.PropertyMetadataSettings.None,
             onSrcPropertyChanged
             )
@@ -99,10 +98,10 @@ export class Image extends view.View implements definition.Image {
         this._setValue(Image.imageSourceProperty, value);
     }
 
-    get src(): string {
+    get src(): any {
         return this._getValue(Image.srcProperty);
     }
-    set src(value: string) {
+    set src(value: any) {
         this._setValue(Image.srcProperty, value);
     }
 
@@ -117,6 +116,10 @@ export class Image extends view.View implements definition.Image {
         this._setValue(Image.stretchProperty, value);
     }
 
+    public _setNativeImage(nativeImage: any) {
+        //
+    }
+
     public onMeasure(widthMeasureSpec: number, heightMeasureSpec: number): void {
 
         // We don't call super because we measure native view with specific size.     
diff --git a/ui/image/image.android.ts b/ui/image/image.android.ts
index 3ecf995a9..b0c566d3d 100644
--- a/ui/image/image.android.ts
+++ b/ui/image/image.android.ts
@@ -36,9 +36,7 @@ function onImageSourcePropertyChanged(data: dependencyObservable.PropertyChangeD
         return;
     }
 
-    if (image.android) {
-        image.android.setImageBitmap(data.newValue ? data.newValue.android : null);
-    }
+    image._setNativeImage(data.newValue ? data.newValue.android : null);
 }
 
 // register the setNativeValue callback
@@ -55,4 +53,8 @@ export class Image extends imageCommon.Image {
     public _createUI() {
         this._android = new android.widget.ImageView(this._context);
     }
+
+    public _setNativeImage(nativeImage: any) {
+        this.android.setImageBitmap(nativeImage);
+    }
 }
\ No newline at end of file
diff --git a/ui/image/image.d.ts b/ui/image/image.d.ts
index 3a506e352..27b8b6ab5 100644
--- a/ui/image/image.d.ts
+++ b/ui/image/image.d.ts
@@ -31,9 +31,9 @@ declare module "ui/image" {
         imageSource: imageSource.ImageSource;
 
         /**
-         * Gets or sets the URL of the image.
+         * Gets or sets the source of the Image. This can be either an URL string or a native image instance.
          */
-        src: string;
+        src: any;
 
         /**
          * Gets a value indicating if the image is currently loading
diff --git a/ui/image/image.ios.ts b/ui/image/image.ios.ts
index 76b642a89..268d81097 100644
--- a/ui/image/image.ios.ts
+++ b/ui/image/image.ios.ts
@@ -30,20 +30,18 @@ function onStretchPropertyChanged(data: dependencyObservable.PropertyChangeData)
 
 function onImageSourcePropertyChanged(data: dependencyObservable.PropertyChangeData) {
     var image = <Image>data.object;
-    image.ios.image = data.newValue ? data.newValue.ios : null;
-
-    if (isNaN(image.width) || isNaN(image.height)) {
-        image.requestLayout();
-    }
+    image._setNativeImage(data.newValue ? data.newValue.ios : null);
 }
 
 // register the setNativeValue callback
 (<proxy.PropertyMetadata>imageCommon.Image.imageSourceProperty.metadata).onSetNativeValue = onImageSourcePropertyChanged;
 (<proxy.PropertyMetadata>imageCommon.Image.stretchProperty.metadata).onSetNativeValue = onStretchPropertyChanged;
 
+
+
 export class Image extends imageCommon.Image {
     private _ios: UIImageView;
-    
+
     constructor(options?: definition.Options) {
         super(options);
 
@@ -57,4 +55,12 @@ export class Image extends imageCommon.Image {
     get ios(): UIImageView {
         return this._ios;
     }
+
+    public _setNativeImage(nativeImage: any) {
+        this.ios.image = nativeImage;
+
+        if (isNaN(this.width) || isNaN(this.height)) {
+            this.requestLayout();
+        }
+    }
 } 
\ No newline at end of file