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crowmagnumbNathanWalker
crowmagnumb
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NathanWalker
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feat(ImageSource): resize method (#8678)
1 parent f4313e3 commit 6081343

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‎api-reports/NativeScript.api.md‎

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@@ -1198,6 +1198,8 @@ export class ImageSource {
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// @deprecated (undocumented)
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loadFromResource(name: string): boolean;
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resize(maxSize: number, options?: any): ImageSource;
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rotationAngle: number;
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saveToFile(path: string, format: "png" | "jpeg" | "jpg", quality?: number): boolean;

‎nativescript-core/image-source/image-source-common.ts‎

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export function getScaledDimensions(
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width: number,
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height: number,
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maxSize: number
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) {
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if (height >= width) {
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if (height <= maxSize) {
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// if image already smaller than the required height
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return { width, height };
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}
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return {
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width: Math.round((maxSize * width) / height),
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height: maxSize
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};
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}
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if (width <= maxSize) {
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// if image already smaller than the required width
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return { width, height };
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}
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return {
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width: maxSize,
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height: Math.round((maxSize * height) / width)
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};
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}

‎nativescript-core/image-source/image-source.android.ts‎

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@@ -10,6 +10,8 @@ import { getNativeApplication } from "../application";
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import { Font } from "../ui/styling/font";
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import { Color } from "../color";
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import { getScaledDimensions } from "./image-source-common";
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export { isFileOrResourcePath };
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let http: typeof httpModule;
@@ -337,6 +339,18 @@ export class ImageSource implements ImageSourceDefinition {
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return outputStream.toString();
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}
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public resize(maxSize: number, options?: any): ImageSource {
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const dim = getScaledDimensions(this.android.getWidth(), this.android.getHeight(), maxSize);
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const bm: android.graphics.Bitmap = android.graphics.Bitmap.createScaledBitmap(
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this.android,
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dim.width,
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dim.height,
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options && options.filter
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);
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return new ImageSource(bm);
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}
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}
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function getTargetFormat(format: "png" | "jpeg" | "jpg"): android.graphics.Bitmap.CompressFormat {

‎nativescript-core/image-source/image-source.d.ts‎

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@@ -209,6 +209,19 @@ export class ImageSource {
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* @param quality Optional parameter, specifying the quality of the encoding. Defaults to the maximum available quality. Quality varies on a scale of 0 to 100.
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*/
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toBase64String(format: "png" | "jpeg" | "jpg", quality?: number): string;
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/**
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* Returns a new ImageSource that is a resized version of this image with the same aspect ratio, but the max dimension set to the provided maxSize.
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* @param maxSize The maximum pixel dimension of the resulting image.
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* @param options Optional parameter, Only used for android, options.filter is a boolean which
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* determines whether or not bilinear filtering should be used when scaling the bitmap.
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* If this is true then bilinear filtering will be used when scaling which has
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* better image quality at the cost of worse performance. If this is false then
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* nearest-neighbor scaling is used instead which will have worse image quality
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* but is faster. Recommended default is to set filter to 'true' as the cost of
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* bilinear filtering is typically minimal and the improved image quality is significant.
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*/
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resize(maxSize: number, options?: any): ImageSource;
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}
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/**

‎nativescript-core/image-source/image-source.ios.ts‎

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@@ -9,6 +9,8 @@ import { Color } from "../color";
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import { path as fsPath, knownFolders } from "../file-system";
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import { isFileOrResourcePath, RESOURCE_PREFIX, layout } from "../utils/utils";
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import { getScaledDimensions } from "./image-source-common";
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export { isFileOrResourcePath };
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let http: typeof httpModule;
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return res;
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}
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public resize(maxSize: number, options?: any): ImageSource {
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const size: CGSize = this.ios.size;
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const dim = getScaledDimensions(
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size.width,
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size.height,
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maxSize
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);
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const newSize: CGSize = CGSizeMake(dim.width, dim.height);
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UIGraphicsBeginImageContextWithOptions(newSize, true, this.ios.scale);
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this.ios.drawInRect(CGRectMake(0, 0, newSize.width, newSize.height));
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const resizedImage = UIGraphicsGetImageFromCurrentImageContext();
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UIGraphicsEndImageContext();
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return new ImageSource(resizedImage);
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}
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}
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function getFileName(path: string): string {

‎tests/app/image-source/image-source-tests.ts‎

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@@ -295,3 +295,13 @@ export function testLoadFromFontIconCode() {
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TKUnit.assert(img.width !== null, "img.width");
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TKUnit.assert(img.height !== null, "img.width");
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}
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export function testResize() {
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const img = ImageSource.fromFileSync(imagePath);
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const newSize = Math.floor(Math.max(img.width, img.height) / 2);
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const resized = img.resize(newSize);
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TKUnit.assert(resized.width === newSize || resized.height === newSize, "Image not resized correctly");
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}

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