async image loading from data, files and resources for ios

Use the tns_safeDecodeImageNamedCompletion from the widgets framework

Add loadMode on Image with sync and async options for local images

image-source/image-source.android.ts

@@ -44,7 +44,7 @@ export class ImageSource implements definition.ImageSource {
                 // Load BitmapDrawable with getDrawable to make use of Android internal caching
                 var bitmapDrawable = <android.graphics.drawable.BitmapDrawable>res.getDrawable(identifier);
                 if (bitmapDrawable && bitmapDrawable.getBitmap) {
-                    this.android  = bitmapDrawable.getBitmap();
+                    this.android = bitmapDrawable.getBitmap();
                 }
             }
         }
@@ -52,6 +52,12 @@ export class ImageSource implements definition.ImageSource {
         return this.android != null;
     }
 
+    public fromResource(name: string): Promise<boolean> {
+        return new Promise<boolean>((resolve, reject) => {
+            resolve(this.loadFromResource(name));
+        });
+    }
+
     public loadFromFile(path: string): boolean {
         ensureFS();
 
@@ -64,11 +70,23 @@ export class ImageSource implements definition.ImageSource {
         return this.android != null;
     }
 
+    public fromFile(path: string): Promise<boolean> {
+        return new Promise<boolean>((resolve, reject) => {
+            resolve(this.loadFromFile(path));
+        });
+    }
+
     public loadFromData(data: any): boolean {
         this.android = android.graphics.BitmapFactory.decodeStream(data);
         return this.android != null;
     }
 
+    public fromData(data: any): Promise<boolean> {
+        return new Promise<boolean>((resolve, reject) => {
+            resolve(this.loadFromData(data));
+        });
+    }
+
     public loadFromBase64(source: string): boolean {
         if (types.isString(source)) {
             var bytes = android.util.Base64.decode(source, android.util.Base64.DEFAULT);
@@ -77,6 +95,12 @@ export class ImageSource implements definition.ImageSource {
         return this.android != null;
     }
 
+    public fromBase64(data: any): Promise<boolean> {
+        return new Promise<boolean>((resolve, reject) => {
+            resolve(this.loadFromBase64(data));
+        });
+    }
+
     public setNativeSource(source: any): boolean {
         this.android = source;
         return source != null;

image-source/image-source.d.ts

@@ -33,23 +33,47 @@ declare module "image-source" {
         */
         loadFromResource(name: string): boolean;
 
+       /**
+        * Loads this instance from the specified resource name asynchronously.
+        * @param name The name of the resource (without its extension).
+        */
+        fromResource(name: string): Promise<boolean>;
+        
        /**
         * Loads this instance from the specified file.
         * @param path The location of the file on the file system.
         */
         loadFromFile(path: string): boolean;
 
+       /**
+        * Loads this instance from the specified file asynchronously.
+        * @param path The location of the file on the file system.
+        */
+        fromFile(path: string): Promise<boolean>;
+
        /**
         * Loads this instance from the specified native image data.
         * @param data The native data (byte array) to load the image from. This will be either Stream for Android or NSData for iOS.
         */
         loadFromData(data: any): boolean;
+        
+       /**
+        * Loads this instance from the specified native image data asynchronously.
+        * @param data The native data (byte array) to load the image from. This will be either Stream for Android or NSData for iOS.
+        */
+        fromData(data: any): Promise<boolean>;        
 
         /**
          * Loads this instance from the specified native image data.
          * @param source The Base64 string to load the image from.
          */
         loadFromBase64(source: string): boolean;
+        
+        /**
+         * Loads this instance from the specified native image data asynchronously.
+         * @param source The Base64 string to load the image from.
+         */
+        fromBase64(source: string): Promise<boolean>;        
 
        /**
         * Sets the provided native source object (typically a Bitmap).

image-source/image-source.ios.ts

@@ -11,10 +11,30 @@ export class ImageSource implements definition.ImageSource {
     public ios: UIImage;
 
     public loadFromResource(name: string): boolean {
-        this.ios = UIImage.imageNamed(name) || UIImage.imageNamed(`${name}.jpg`);
+        this.ios = (<any>UIImage).tns_safeImageNamed(name) || (<any>UIImage).tns_safeImageNamed(`${name}.jpg`);
         return this.ios != null;
     }
 
+    public fromResource(name: string): Promise<boolean> {
+        return new Promise<boolean>((resolve, reject) => {
+            try {
+                (<any>UIImage).tns_safeDecodeImageNamedCompletion(name, image => {
+                    if (image) {
+                        this.ios = image;
+                        resolve(true);
+                    } else {
+                        (<any>UIImage).tns_safeDecodeImageNamedCompletion(`${name}.jpg`, image => {
+                            this.ios = image;
+                            resolve(true);
+                        });
+                    }
+                });
+            } catch (ex) {
+                reject(ex);
+            }
+        });
+    }
+
     public loadFromFile(path: string): boolean {
         var fileName = types.isString(path) ? path.trim() : "";
 
@@ -26,19 +46,67 @@ export class ImageSource implements definition.ImageSource {
         return this.ios != null;
     }
 
+    public fromFile(path: string): Promise<boolean> {
+        return new Promise<boolean>((resolve, reject) => {
+            try {
+                var fileName = types.isString(path) ? path.trim() : "";
+
+                if (fileName.indexOf("~/") === 0) {
+                    fileName = fs.path.join(fs.knownFolders.currentApp().path, fileName.replace("~/", ""));
+                }
+
+                (<any>UIImage).tns_decodeImageWidthContentsOfFileCompletion(fileName, image => {
+                    this.ios = image;
+                    resolve(true);
+                });
+            } catch (ex) {
+                reject(ex);
+            }
+        });
+    }
+
     public loadFromData(data: any): boolean {
         this.ios = UIImage.imageWithData(data);
         return this.ios != null;
     }
 
+    public fromData(data: any): Promise<boolean> {
+        return new Promise<boolean>((resolve, reject) => {
+            try {
+                (<any>UIImage).tns_decodeImageWithDataCompletion(data, image => {
+                    this.ios = image;
+                    resolve(true);
+                });
+            } catch (ex) {
+                reject(ex);
+            }
+        });
+    }
+
     public loadFromBase64(source: string): boolean {
         if (types.isString(source)) {
             var data = NSData.alloc().initWithBase64EncodedStringOptions(source, NSDataBase64DecodingOptions.NSDataBase64DecodingIgnoreUnknownCharacters);
             this.ios = UIImage.imageWithData(data);
         }
+
         return this.ios != null;
     }
 
+    public fromBase64(source: string): Promise<boolean> {
+        return new Promise<boolean>((resolve, reject) => {
+            try {
+                var data = NSData.alloc().initWithBase64EncodedStringOptions(source, NSDataBase64DecodingOptions.NSDataBase64DecodingIgnoreUnknownCharacters);
+                UIImage.imageWithData["async"](UIImage, [data]).then(image => {
+                    this.ios = image;
+                    resolve(true);
+                });
+
+            } catch (ex) {
+                reject(ex);
+            }
+        });
+    }
+
     public setNativeSource(source: any): boolean {
         this.ios = source;
         return source != null;
@@ -103,4 +171,4 @@ function getImageData(instance: UIImage, format: string, quality = 1.0): NSData
 
     }
     return data;
-}
+}