本文的目的是介绍如何设计一个好用的ReactImage组件？的详细情况，特别关注react组件设计原则的相关信息。我们将通过专业的研究、有关数据的分析等多种方式，为您呈现一个全面的了解如何设计一个好用
本文的目的是介绍如何设计一个好用的 React Image 组件？的详细情况，特别关注react组件设计原则的相关信息。我们将通过专业的研究、有关数据的分析等多种方式，为您呈现一个全面的了解如何设计一个好用的 React Image 组件？的机会，同时也不会遗漏关于Android 设计一个菱形形状的Imageview组件.、com.facebook.imagepipeline.image.CloseableAnimatedImage的实例源码、com.facebook.react.views.image.ImageResizeMode的实例源码、com.facebook.react.views.image.ReactImageManager的实例源码的知识。
本文目录一览：- 如何设计一个好用的 React Image 组件？（react组件设计原则）
- Android 设计一个菱形形状的Imageview组件.
- com.facebook.imagepipeline.image.CloseableAnimatedImage的实例源码
- com.facebook.react.views.image.ImageResizeMode的实例源码
- com.facebook.react.views.image.ReactImageManager的实例源码
如何设计一个好用的 React Image 组件？（react组件设计原则）
前言
本文为笔者阅读 react-image[1] 源码过程中的总结，若有所错漏烦请指出。✨ 仓库传送门[2]
https://github.com/worldzhao/blog/issues/1
<img />可以说是开发过程中极其常用的标签了。但是很多同学都是<img src="xxx.png" />一把梭，直到 UI 小姐姐来找你谈谈人生理想：
-
图片加载太慢，需要展示 loading占位符； -
图片加载失败，加载备选图片或展示 error占位符。
作为开发者的我们，可能会经历以下几个阶段：
-
第一阶段： img标签上使用onLoad以及onError进行处理； -
第二阶段：写一个较为通用的组件； -
第三阶段：抽离 hooks，使用方自定义视图组件（当然也要提供基本组件）；
现在让我们直接从第三阶段开始，看看如何使用少量代码打造一个易用性、封装性以及扩展性俱佳的image组件。
useImage
首先分析可复用的逻辑，可以发现使用者需要关注三个状态：loading、error以及src，毕竟加载图片也是异步请求嘛。
对 react-use[3] 熟悉的同学会很容易联想到
useAsync。
自定义一个 hooks，接收图片链接作为参数，返回调用方需要的三个状态。
基础实现
import * as React from "react";
// 将图片加载转为promise调用形式
function imgPromise(src: string) {
return new Promise((resolve, reject) => {
const i = new Image();
i.onload = () => resolve();
i.onerror = reject;
i.src = src;
});
}
function useImage({ src }: { src: string }): {
src: string | undefined,
isLoading: boolean,
error: any,
} {
const [loading, setLoading] = React.useState(true);
const [error, setError] = React.useState(null);
const [value, setValue] = (React.useState < string) | (undefined > undefined);
React.useEffect(() => {
imgPromise(src)
.then(() => {
// 加载成功
setLoading(false);
setValue(src);
})
.catch((error) => {
// 加载失败
setLoading(false);
setError(error);
});
}, [src]);
return { isLoading: loading, src: value, error: error };
}
我们已经完成了最基础的实现，现在来慢慢优化。
性能优化
对于同一张图片来讲，在组件 A 加载过的图片，组件 B 不用再走一遍new Image()的流程，直接返回上一次结果即可。
+ const cache: {
+ [key: string]: Promise<void>;
+ } = {};
function useImage({
src,
}: {
src: string;
}): { src: string | undefined; isLoading: boolean; error: any } {
const [loading, setLoading] = React.useState(true);
const [error, setError] = React.useState(null);
const [value, setValue] = React.useState<string | undefined>(undefined);
React.useEffect(() => {
+ if (!cache[src]) {
+ cache[src] = imgPromise(src);
+ }
- imgPromise(src)
+ cache[src]
.then(() => {
setLoading(false);
setValue(src);
})
.catch(error => {
setLoading(false);
setError(error);
});
}, [src]);
return { isLoading: loading, src: value, error: error };
}
优化了一丢丢性能。
支持 srcList
上文提到过一点：图片加载失败，加载备选图片或展示error占位符。
展示error占位符我们可以通过error状态去控制，但是加载备选图片的功能还没有完成。
主要思路如下：
-
将入参 src改为srcList，值为图片url或图片（含备选图片）的url数组； -
从第一张开始加载，若失败则加载第二张，直到某一张成功或全部失败，流程结束。类似于 tapable [4] 的 AsyncSeriesBailHook。
对入参进行处理：
const removeBlankArrayElements = (a: string[]) => a.filter((x) => x);
const stringToArray = (x: string | string[]) => (Array.isArray(x) ? x : [x]);
function useImage({ srcList }: { srcList: string | string[] }): {
src: string | undefined,
loading: boolean,
error: any,
} {
// 获取url数组
const sourceList = removeBlankArrayElements(stringToArray(srcList));
// 获取用于缓存的键名
const sourceKey = sourceList.join("");
}
接下来就是重要的加载流程啦，定义promiseFind方法，用于完成以上加载图片的逻辑。
/**
* 注意 此处将imgPromise作为参数传入，而没有直接使用imgPromise
* 主要是为了扩展性
* 后面会将imgPromise方法作为一个参数由使用者传入，使得使用者加载图片的操作空间更大
* 当然若使用者不传该参数，就是用默认的imgPromise方法
*/
function promiseFind(
sourceList: string[],
imgPromise: (src: string) => Promise<void>
): Promise<string> {
let done = false;
// 重新使用Promise包一层
return new Promise((resolve, reject) => {
const queueNext = (src: string) => {
return imgPromise(src).then(() => {
done = true;
// 加载成功 resolve
resolve(src);
});
};
const firstPromise = queueNext(sourceList.shift() || "");
// 生成一条promise链[队列]，每一个promise都跟着catch方法处理当前promise的失败
// 从而继续下一个promise的处理
sourceList
.reduce((p, src) => {
// 如果加载失败 继续加载
return p.catch(() => {
if (!done) return queueNext(src);
return;
});
}, firstPromise)
// 全都挂了 reject
.catch(reject);
});
}
再来改动useImage。
const cache: {
- [key: string]: Promise<void>;
+ [key: string]: Promise<string>;
} = {};
function useImage({
- src,
+ srcList,
}: {
- src: string;
+ srcList: string | string[];
}): { src: string | undefined; loading: boolean; error: any } {
const [loading, setLoading] = React.useState(true);
const [error, setError] = React.useState(null);
const [value, setValue] = React.useState<string | undefined>(undefined);
// 图片链接数组
+ const sourceList = removeBlankArrayElements(stringToArray(srcList));
// cache唯一键名
+ const sourceKey = sourceList.join('''');
React.useEffect(() => {
- if (!cache[src]) {
- cache[src] = imgPromise(src);
- }
+ if (!cache[sourceKey]) {
+ cache[sourceKey] = promiseFind(sourceList, imgPromise);
+ }
- cache[src]
- .then(() => {
+ cache[sourceKey]
+ .then((src) => {
setLoading(false);
setValue(src);
})
.catch(error => {
setLoading(false);
setError(error);
});
}, [src]);
return { isLoading: loading, src: value, error: error };
}
需要注意的一点：现在传入的图片链接可能不是单个src，最终设置的value为promiseFind找到的src，所以 cache 类型定义也有变化。
自定义 imgPromise
前面提到过，加载图片过程中，使用方可能会插入自己的逻辑，所以将 imgPromise 方法作为可选参数loadImg传入，若使用者想自定义加载方法，可传入该参数。
function useImage({
+ loadImg = imgPromise,
srcList,
}: {
+ loadImg?: (src: string) => Promise<void>;
srcList: string | string[];
}): { src: string | undefined; loading: boolean; error: any } {
const [loading, setLoading] = React.useState(true);
const [error, setError] = React.useState(null);
const [value, setValue] = React.useState<string | undefined>(undefined);
const sourceList = removeBlankArrayElements(stringToArray(srcList));
const sourceKey = sourceList.join('''');
React.useEffect(() => {
if (!cache[sourceKey]) {
- cache[sourceKey] = promiseFind(sourceList, imgPromise);
+ cache[sourceKey] = promiseFind(sourceList, loadImg);
}
cache[sourceKey]
.then(src => {
setLoading(false);
setValue(src);
})
.catch(error => {
setLoading(false);
setError(error);
});
}, [sourceKey]);
return { loading: loading, src: value, error: error };
}
实现 Img 组件
完成useImage后，我们就可以基于其实现 Img 组件了。
预先定义好相关 API：
属性 说明 类型 默认值 src 图片链接 string / string[] - loader 可选，加载过程占位元素 ReactNode null unloader 可选，加载失败占位元素 ReactNode null loadImg 可选，图片加载方法，返回一个 Promise (src:string)=>Promise imgPromise 当然，除了以上 API，还有<img />标签原生属性。编写类型声明文件如下：
export type ImgProps = Omit<
React.DetailedHTMLProps<
React.ImgHTMLAttributes<HTMLImageElement>,
HTMLImageElement
>,
"src"
> &
Omit<useImageParams, "srcList"> & {
src: useImageParams["srcList"];
loader?: JSX.Element | null;
unloader?: JSX.Element | null;
};
实现如下：
export default ({
src: srcList,
loadImg,
loader = null,
unloader = null,
...imgProps
}: ImgProps) => {
const { src, loading, error } = useImage({
srcList,
loadImg,
});
if (src) return <img src={src} {...imgProps} />;
if (loading) return loader;
if (error) return unloader;
return null;
};
测试效果如下：
结语
值得注意的是，本文遵循 react-image 大体思路，但部分内容暂未实现（所以代码可读性要好一点）。其它特性，如：
-
支持 Suspense 形式调用； -
默认在渲染图片前会进行 decode，避免页面卡顿或者闪烁。
有兴趣的同学可以看看下面这些文章：
-
用于数据获取的 Suspense（试验阶段） [5] -
错误边界（Error Boundaries） [6] -
React：Suspense 的实现与探讨 [7] -
HTMLImageElement.decode() [8] -
Chrome 图片解码与 Image.decode API [9]
参考资料
react-image: https://github.com/mbrevda/react-image
[2]✨ 仓库传送门: https://github.com/worldzhao/build-your-own-react-image
[3]react-use: https://github.com/streamich/react-use
[4]tapable: https://github.com/webpack/tapable
[5]用于数据获取的 Suspense（试验阶段）: https://zh-hans.reactjs.org/docs/concurrent-mode-suspense.html
[6]错误边界（Error Boundaries）: https://zh-hans.reactjs.org/docs/error-boundaries.html#introducing-error-boundaries
[7]React：Suspense 的实现与探讨: https://zhuanlan.zhihu.com/p/34210780
[8]HTMLImageElement.decode(): https://developer.mozilla.org/zh-CN/docs/Web/API/HTMLImageElement/decode
[9]Chrome 图片解码与 Image.decode API: https://zhuanlan.zhihu.com/p/43991630
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Android 设计一个菱形形状的Imageview组件.
网上没有资料,特来请教下大神
Android 设计一个菱形形状的Imageview组件. >> android
这个答案描述的挺清楚的：
http://www.goodpm.net/postreply/android/1010000007107851/Android设计一个菱形形状的Imageview组件.html
com.facebook.imagepipeline.image.CloseableAnimatedImage的实例源码
项目：GitHub
文件：BoxingFrescoLoader.java
private Drawable createDrawableFromFetchedResult(Context context,CloseableImage image) {
if (image instanceof CloseableStaticBitmap) {
CloseableStaticBitmap closeableStaticBitmap = (CloseableStaticBitmap) image;
BitmapDrawable bitmapDrawable = createBitmapDrawable(context,closeableStaticBitmap.getUnderlyingBitmap());
return (closeableStaticBitmap.getRotationAngle() != 0 && closeableStaticBitmap.getRotationAngle() != -1 ? new OrientedDrawable(bitmapDrawable,closeableStaticBitmap.getRotationAngle()) : bitmapDrawable);
} else if (image instanceof CloseableAnimatedImage) {
AnimatedDrawableFactory animatedDrawableFactory = Fresco.getimagePipelineFactory().getAnimatedFactory().getAnimatedDrawableFactory(context);
if (animatedDrawableFactory != null) {
AnimatedDrawable animatedDrawable = (AnimatedDrawable) animatedDrawableFactory.create(image);
if (animatedDrawable != null) {
return animatedDrawable;
}
}
}
throw new UnsupportedOperationException("Unrecognized image class: " + image);
}
项目：GitHub
文件：AnimatedSingleUsePostprocessorProducerTest.java
@Test
public void testNonStaticBitmapIsPassedOn() {
SingleUsePostprocessorConsumer postprocessorConsumer = produceResults();
CloseableAnimatedImage sourceCloseableAnimatedImage = mock(CloseableAnimatedImage.class);
CloseableReference<CloseableImage> sourceCloseableImageRef =
CloseableReference.<CloseableImage>of(sourceCloseableAnimatedImage);
postprocessorConsumer.onNewResult(sourceCloseableImageRef,Consumer.IS_LAST);
sourceCloseableImageRef.close();
mTestExecutorService.runUntilIdle();
mInorder.verify(mConsumer).onNewResult(any(CloseableReference.class),eq(Consumer.IS_LAST));
mInorder.verifyNoMoreInteractions();
assertEquals(1,mResults.size());
CloseableReference<CloseableImage> res0 = mResults.get(0);
assertTrue(CloseableReference.isValid(res0));
assertSame(sourceCloseableAnimatedImage,res0.get());
res0.close();
verify(sourceCloseableAnimatedImage).close();
}
项目：GitHub
文件：AnimatedRepeatedPostprocessorProducerTest.java
@Test
public void testNonStaticBitmapIsPassedOn() {
RepeatedPostprocessorConsumer postprocessorConsumer = produceResults();
RepeatedPostprocessorRunner repeatedPostprocessorRunner = getRunner();
CloseableAnimatedImage sourceCloseableAnimatedImage = mock(CloseableAnimatedImage.class);
CloseableReference<CloseableImage> sourceCloseableImageRef =
CloseableReference.<CloseableImage>of(sourceCloseableAnimatedImage);
postprocessorConsumer.onNewResult(sourceCloseableImageRef,eq(Consumer.NO_FLAGS));
mInorder.verifyNoMoreInteractions();
assertEquals(1,res0.get());
res0.close();
performCancelAndVerifyOnCancellation();
verify(sourceCloseableAnimatedImage).close();
}
项目：Boxing
文件：BoxingFrescoLoader.java
private Drawable createDrawableFromFetchedResult(Context context,closeableStaticBitmap.getRotationAngle()) : bitmapDrawable);
} else if (image instanceof CloseableAnimatedImage) {
AnimatedDrawableFactory animatedDrawableFactory = Fresco.getimagePipelineFactory().getAnimatedFactory().getAnimatedDrawableFactory(context);
if (animatedDrawableFactory != null) {
AnimatedDrawable animatedDrawable = (AnimatedDrawable) animatedDrawableFactory.create(image);
if (animatedDrawable != null) {
return animatedDrawable;
}
}
}
throw new UnsupportedOperationException("Unrecognized image class: " + image);
}
项目：fresco
文件：AnimatedSingleUsePostprocessorProducerTest.java
@Test
public void testNonStaticBitmapIsPassedOn() {
SingleUsePostprocessorConsumer postprocessorConsumer = produceResults();
CloseableAnimatedImage sourceCloseableAnimatedImage = mock(CloseableAnimatedImage.class);
CloseableReference<CloseableImage> sourceCloseableImageRef =
CloseableReference.<CloseableImage>of(sourceCloseableAnimatedImage);
postprocessorConsumer.onNewResult(sourceCloseableImageRef,res0.get());
res0.close();
verify(sourceCloseableAnimatedImage).close();
}
项目：fresco
文件：AnimatedRepeatedPostprocessorProducerTest.java
@Test
public void testNonStaticBitmapIsPassedOn() {
RepeatedPostprocessorConsumer postprocessorConsumer = produceResults();
RepeatedPostprocessorRunner repeatedPostprocessorRunner = getRunner();
CloseableAnimatedImage sourceCloseableAnimatedImage = mock(CloseableAnimatedImage.class);
CloseableReference<CloseableImage> sourceCloseableImageRef =
CloseableReference.<CloseableImage>of(sourceCloseableAnimatedImage);
postprocessorConsumer.onNewResult(sourceCloseableImageRef,res0.get());
res0.close();
performCancelAndVerifyOnCancellation();
verify(sourceCloseableAnimatedImage).close();
}
项目：GitHub
文件：AnimatedImageFactoryImpl.java
private CloseableImage getCloseableImage(
ImageDecodeOptions options,AnimatedImage image,Bitmap.Config bitmapConfig) {
List<CloseableReference<Bitmap>> decodedFrames = null;
CloseableReference<Bitmap> previewBitmap = null;
try {
final int frameForPreview = options.useLastFrameForPreview ? image.getFrameCount() - 1 : 0;
if (options.forceStaticImage) {
return new CloseableStaticBitmap(
createPreviewBitmap(image,bitmapConfig,frameForPreview),ImmutableQualityInfo.FULL_QUALITY,0);
}
if (options.decodeAllFrames) {
decodedFrames = decodeAllFrames(image,bitmapConfig);
previewBitmap = CloseableReference.cloneOrNull(decodedFrames.get(frameForPreview));
}
if (options.decodePreviewFrame && previewBitmap == null) {
previewBitmap = createPreviewBitmap(image,frameForPreview);
}
AnimatedImageResult animatedImageResult = AnimatedImageResult.newBuilder(image)
.setPreviewBitmap(previewBitmap)
.setFrameForPreview(frameForPreview)
.setDecodedFrames(decodedFrames)
.build();
return new CloseableAnimatedImage(animatedImageResult);
} finally {
CloseableReference.closeSafely(previewBitmap);
CloseableReference.closeSafely(decodedFrames);
}
}
项目：GitHub
文件：AnimatedImageFactoryWebPImpltest.java
@Test
public void testCreateDefaults() {
WebPImage mockWebPImage = mock(WebPImage.class);
// Expect a call to WebPImage.create
TrivialPooledByteBuffer byteBuffer = createByteBuffer();
when(mWebPImageMock.decode(byteBuffer.getNativePtr(),byteBuffer.size()))
.thenReturn(mockWebPImage);
EncodedImage encodedImage = new EncodedImage(
CloseableReference.of(byteBuffer,FAKE_RESOURCE_RELEASER));
encodedImage.setimageFormat(ImageFormat.UNKNowN);
CloseableAnimatedImage closeableImage =
(CloseableAnimatedImage) mAnimatedImageFactory.decodeWebP(
encodedImage,ImageDecodeOptions.defaults(),DEFAULT_BITMAP_CONfig);
// Verify we got the right result
AnimatedImageResult imageResult = closeableImage.getimageResult();
assertSame(mockWebPImage,imageResult.getimage());
assertNull(imageResult.getPreviewBitmap());
assertFalse(imageResult.hasDecodedFrame(0));
// Should not have interacted with these.
verifyZeroInteractions(mMockAnimatedDrawableBackendProvider);
verifyZeroInteractions(mMockBitmapFactory);
}
项目：GitHub
文件：AnimatedImageFactoryGifImpltest.java
@Test
public void testCreateDefaults() {
GifImage mockGifImage = mock(GifImage.class);
// Expect a call to GifImage.create
TrivialPooledByteBuffer byteBuffer = createByteBuffer();
when(mGifImageMock.decode(byteBuffer.getNativePtr(),byteBuffer.size()))
.thenReturn(mockGifImage);
EncodedImage encodedImage = new EncodedImage(
CloseableReference.of(byteBuffer,FAKE_RESOURCE_RELEASER));
encodedImage.setimageFormat(ImageFormat.UNKNowN);
CloseableAnimatedImage closeableImage =
(CloseableAnimatedImage) mAnimatedImageFactory.decodeGif(
encodedImage,DEFAULT_BITMAP_CONfig);
// Verify we got the right result
AnimatedImageResult imageResult = closeableImage.getimageResult();
assertSame(mockGifImage,imageResult.getimage());
assertNull(imageResult.getPreviewBitmap());
assertFalse(imageResult.hasDecodedFrame(0));
// Should not have interacted with these.
verifyZeroInteractions(mMockAnimatedDrawableBackendProvider);
verifyZeroInteractions(mMockBitmapFactory);
}
项目：fresco
文件：AnimatedImageFactoryImpl.java
private CloseableImage getCloseableImage(
ImageDecodeOptions options,frameForPreview);
}
AnimatedImageResult animatedImageResult = AnimatedImageResult.newBuilder(image)
.setPreviewBitmap(previewBitmap)
.setFrameForPreview(frameForPreview)
.setDecodedFrames(decodedFrames)
.build();
return new CloseableAnimatedImage(animatedImageResult);
} finally {
CloseableReference.closeSafely(previewBitmap);
CloseableReference.closeSafely(decodedFrames);
}
}
项目：fresco
文件：AnimatedImageFactoryWebPImpltest.java
@Test
public void testCreateDefaults() {
WebPImage mockWebPImage = mock(WebPImage.class);
// Expect a call to WebPImage.create
TrivialPooledByteBuffer byteBuffer = createByteBuffer();
when(mWebPImageMock.decode(byteBuffer.getNativePtr(),imageResult.getimage());
assertNull(imageResult.getPreviewBitmap());
assertFalse(imageResult.hasDecodedFrame(0));
// Should not have interacted with these.
verifyZeroInteractions(mMockAnimatedDrawableBackendProvider);
verifyZeroInteractions(mMockBitmapFactory);
}
项目：fresco
文件：AnimatedImageFactoryGifImpltest.java
@Test
public void testCreateDefaults() {
GifImage mockGifImage = mock(GifImage.class);
// Expect a call to GifImage.create
TrivialPooledByteBuffer byteBuffer = createByteBuffer();
when(mGifImageMock.decode(byteBuffer.getNativePtr(),imageResult.getimage());
assertNull(imageResult.getPreviewBitmap());
assertFalse(imageResult.hasDecodedFrame(0));
// Should not have interacted with these.
verifyZeroInteractions(mMockAnimatedDrawableBackendProvider);
verifyZeroInteractions(mMockBitmapFactory);
}
项目：GitHub
文件：ExperimentalBitmapAnimationDrawableFactory.java
@Override
public boolean supportsImageType(CloseableImage image) {
return image instanceof CloseableAnimatedImage;
}
项目：GitHub
文件：ExperimentalBitmapAnimationDrawableFactory.java
@Override
public AnimatedDrawable2 createDrawable(CloseableImage image) {
return new AnimatedDrawable2(
createAnimationBackend(
((CloseableAnimatedImage) image).getimageResult()));
}
项目：GitHub
文件：AnimatedImageFactoryWebPImpltest.java
@Test
public void testCreateWithPreviewBitmap() throws Exception {
WebPImage mockWebPImage = mock(WebPImage.class);
Bitmap mockBitmap = MockBitmapFactory.create(50,50,DEFAULT_BITMAP_CONfig);
// Expect a call to WebPImage.create
TrivialPooledByteBuffer byteBuffer = createByteBuffer();
when(mWebPImageMock.decode(byteBuffer.getNativePtr(),byteBuffer.size()))
.thenReturn(mockWebPImage);
when(mockWebPImage.getWidth()).thenReturn(50);
when(mockWebPImage.getHeight()).thenReturn(50);
// For decoding preview frame,expect some calls.
final AnimatedDrawableBackend mockAnimatedDrawableBackend =
createAnimatedDrawableBackendMock(1);
when(mMockAnimatedDrawableBackendProvider.get(
any(AnimatedImageResult.class),isNull(Rect.class)))
.thenReturn(mockAnimatedDrawableBackend);
when(mMockBitmapFactory.createBitmapInternal(50,DEFAULT_BITMAP_CONfig))
.thenReturn(CloseableReference.of(mockBitmap,FAKE_BITMAP_RESOURCE_RELEASER));
AnimatedImageCompositor mockCompositor = mock(AnimatedImageCompositor.class);
powermockito.whenNew(AnimatedImageCompositor.class)
.withAnyArguments()
.thenReturn(mockCompositor);
ImageDecodeOptions imageDecodeOptions = ImageDecodeOptions.newBuilder()
.setDecodePreviewFrame(true)
.build();
EncodedImage encodedImage = new EncodedImage(
CloseableReference.of(byteBuffer,FAKE_RESOURCE_RELEASER));
encodedImage.setimageFormat(ImageFormat.UNKNowN);
CloseableAnimatedImage closeableImage =
(CloseableAnimatedImage) mAnimatedImageFactory.decodeWebP(
encodedImage,imageDecodeOptions,imageResult.getimage());
assertNotNull(imageResult.getPreviewBitmap());
assertFalse(imageResult.hasDecodedFrame(0));
// Should not have interacted with these.
verify(mMockAnimatedDrawableBackendProvider).get(
any(AnimatedImageResult.class),isNull(Rect.class));
verifyNoMoreInteractions(mMockAnimatedDrawableBackendProvider);
verify(mMockBitmapFactory).createBitmapInternal(50,DEFAULT_BITMAP_CONfig);
verifyNoMoreInteractions(mMockBitmapFactory);
verify(mockCompositor).renderFrame(0,mockBitmap);
}
项目：GitHub
文件：AnimatedImageFactoryWebPImpltest.java
@Test
public void testCreateWithDecodeAlFrames() throws Exception {
WebPImage mockWebPImage = mock(WebPImage.class);
Bitmap mockBitmap1 = MockBitmapFactory.create(50,DEFAULT_BITMAP_CONfig);
Bitmap mockBitmap2 = MockBitmapFactory.create(50,expect some calls.
final AnimatedDrawableBackend mockAnimatedDrawableBackend =
createAnimatedDrawableBackendMock(2);
when(
mMockAnimatedDrawableBackendProvider.get(
any(AnimatedImageResult.class),isNull(Rect.class)))
.thenReturn(mockAnimatedDrawableBackend);
when(mMockBitmapFactory.createBitmapInternal(50,DEFAULT_BITMAP_CONfig))
.thenReturn(CloseableReference.of(mockBitmap1,FAKE_BITMAP_RESOURCE_RELEASER))
.thenReturn(CloseableReference.of(mockBitmap2,FAKE_BITMAP_RESOURCE_RELEASER));
AnimatedImageCompositor mockCompositor = mock(AnimatedImageCompositor.class);
powermockito.whenNew(AnimatedImageCompositor.class)
.withAnyArguments()
.thenReturn(mockCompositor);
ImageDecodeOptions imageDecodeOptions = ImageDecodeOptions.newBuilder()
.setDecodePreviewFrame(true)
.setDecodeAllFrames(true)
.build();
EncodedImage encodedImage = new EncodedImage(
CloseableReference.of(byteBuffer,imageResult.getimage());
assertNotNull(imageResult.getDecodedFrame(0));
assertNotNull(imageResult.getDecodedFrame(1));
assertNotNull(imageResult.getPreviewBitmap());
// Should not have interacted with these.
verify(mMockAnimatedDrawableBackendProvider).get(
any(AnimatedImageResult.class),isNull(Rect.class));
verifyNoMoreInteractions(mMockAnimatedDrawableBackendProvider);
verify(mMockBitmapFactory,times(2)).createBitmapInternal(50,mockBitmap1);
verify(mockCompositor).renderFrame(1,mockBitmap2);
}
项目：GitHub
文件：AnimatedImageFactoryGifImpltest.java
@Test
public void testCreateWithPreviewBitmap() throws Exception {
GifImage mockGifImage = mock(GifImage.class);
Bitmap mockBitmap = MockBitmapFactory.create(50,DEFAULT_BITMAP_CONfig);
// Expect a call to WebPImage.create
TrivialPooledByteBuffer byteBuffer = createByteBuffer();
when(mGifImageMock.decode(byteBuffer.getNativePtr(),byteBuffer.size()))
.thenReturn(mockGifImage);
when(mockGifImage.getWidth()).thenReturn(50);
when(mockGifImage.getHeight()).thenReturn(50);
// For decoding preview frame,expect some calls.
final AnimatedDrawableBackend mockAnimatedDrawableBackend =
createAnimatedDrawableBackendMock(1);
when(mMockAnimatedDrawableBackendProvider.get(
any(AnimatedImageResult.class),FAKE_RESOURCE_RELEASER));
encodedImage.setimageFormat(ImageFormat.UNKNowN);
CloseableAnimatedImage closeableImage =
(CloseableAnimatedImage) mAnimatedImageFactory.decodeGif(
encodedImage,mockBitmap);
}
项目：GitHub
文件：AnimatedImageFactoryGifImpltest.java
@Test
public void testCreateWithDecodeAlFrames() throws Exception {
GifImage mockGifImage = mock(GifImage.class);
Bitmap mockBitmap1 = MockBitmapFactory.create(50,DEFAULT_BITMAP_CONfig);
// Expect a call to GifImage.create
TrivialPooledByteBuffer byteBuffer = createByteBuffer();
when(mGifImageMock.decode(byteBuffer.getNativePtr(),expect some calls.
final AnimatedDrawableBackend mockAnimatedDrawableBackend =
createAnimatedDrawableBackendMock(2);
when(
mMockAnimatedDrawableBackendProvider.get(
any(AnimatedImageResult.class),mockBitmap2);
}
项目：fresco
文件：ExperimentalBitmapAnimationDrawableFactory.java
@Override
public boolean supportsImageType(CloseableImage image) {
return image instanceof CloseableAnimatedImage;
}
项目：fresco
文件：ExperimentalBitmapAnimationDrawableFactory.java
@Override
public AnimatedDrawable2 createDrawable(CloseableImage image) {
return new AnimatedDrawable2(
createAnimationBackend(
((CloseableAnimatedImage) image).getimageResult()));
}
项目：fresco
文件：AnimatedImageFactoryWebPImpltest.java
@Test
public void testCreateWithPreviewBitmap() throws Exception {
WebPImage mockWebPImage = mock(WebPImage.class);
Bitmap mockBitmap = MockBitmapFactory.create(50,mockBitmap);
}
项目：fresco
文件：AnimatedImageFactoryWebPImpltest.java
@Test
public void testCreateWithDecodeAlFrames() throws Exception {
WebPImage mockWebPImage = mock(WebPImage.class);
Bitmap mockBitmap1 = MockBitmapFactory.create(50,mockBitmap2);
}
项目：fresco
文件：AnimatedImageFactoryGifImpltest.java
@Test
public void testCreateWithPreviewBitmap() throws Exception {
GifImage mockGifImage = mock(GifImage.class);
Bitmap mockBitmap = MockBitmapFactory.create(50,mockBitmap);
}
项目：fresco
文件：AnimatedImageFactoryGifImpltest.java
@Test
public void testCreateWithDecodeAlFrames() throws Exception {
GifImage mockGifImage = mock(GifImage.class);
Bitmap mockBitmap1 = MockBitmapFactory.create(50,mockBitmap2);
}
项目：CanPhotos
文件：CanViewPagerActivity.java
private void handleAnimateBitmap(CloseableAnimatedImage animatedImage,int position) {
AnimatedDrawableFactory animatedDrawableFactory =
Fresco.getimagePipelineFactory().getAnimatedDrawableFactory();
AnimatedDrawable drawable =
animatedDrawableFactory.create(animatedImage.getimageResult());
Bitmap bitmap = drawable2Bitmap(drawable);
map.put(position,bitmap);
}
com.facebook.react.views.image.ImageResizeMode的实例源码
项目：RNLearn_Project1
文件：RCtimageView.java
@H_301_7@
@ReactProp(name = ViewProps.RESIZE_MODE)
public void setResizeMode(@Nullable String resizeMode) {
ScaleType scaleType = ImageResizeMode.toScaleType(resizeMode);
if (mDrawImage.getScaleType() != scaleType) {
getMutableDrawImage().setScaleType(scaleType);
}
}
com.facebook.react.views.image.ReactImageManager的实例源码
项目：react-native-gcm-android
文件：MainReactPackage.java
@Override
public List<ViewManager> createViewManagers(ReactApplicationContext reactContext) {
return Arrays.<ViewManager>asList(
new ReactDrawerLayoutManager(),new ReacthorizontalscrollviewManager(),new ReactimageManager(),new ReactProgressBarViewManager(),new ReactRawTextManager(),new ReactScrollViewManager(),new ReactSwitchManager(),new ReactTextInputManager(),new ReactTextViewManager(),new ReactToolbarManager(),new ReactViewManager(),new ReactViewPagerManager(),new ReactTextInlineImageViewManager(),new ReactVirtualTextViewManager(),new SwipeRefreshLayoutManager(),new ReactWebViewManager());
}
项目：ReactNativeSignatureExample
文件：MainReactPackage.java
@Override
public List<ViewManager> createViewManagers(ReactApplicationContext reactContext) {
return Arrays.<ViewManager>asList(
ARTRenderableViewManager.createARTGroupViewManager(),ARTRenderableViewManager.createARTShapeViewManager(),ARTRenderableViewManager.createARTTextViewManager(),new ARTSurfaceViewManager(),new ReactDialogPickerManager(),new ReactDrawerLayoutManager(),new ReactDropdownPickerManager(),new FrescoBasedReactTextInlineImageViewManager(),new ReactWebViewManager(),new RecyclerViewBackedScrollViewManager(),new SwipeRefreshLayoutManager());
}
项目：react-native-ibeacon-android
文件：MainReactPackage.java
@Override
public List<ViewManager> createViewManagers(ReactApplicationContext reactContext) {
return Arrays.<ViewManager>asList(
ARTRenderableViewManager.createARTGroupViewManager(),new SwipeRefreshLayoutManager());
}
项目：react-native-Box-loaders
文件：MainReactPackage.java
@Override
public List<ViewManager> createViewManagers(ReactApplicationContext reactContext) {
return Arrays.<ViewManager>asList(
ARTRenderableViewManager.createARTGroupViewManager(),new ReactModalHostManager(),new ReactSliderManager(),new SwipeRefreshLayoutManager());
}
项目：Ironman
文件：MainReactPackage.java
@Override
public List<ViewManager> createViewManagers(ReactApplicationContext reactContext) {
return Arrays.<ViewManager>asList(
ARTRenderableViewManager.createARTGroupViewManager(),new SwipeRefreshLayoutManager());
}
项目：RNLearn_Project1
文件：MainReactPackage.java
@Override
public List<ViewManager> createViewManagers(ReactApplicationContext reactContext) {
List<ViewManager> viewManagers = new ArrayList<>();
viewManagers.add(ARTRenderableViewManager.createARTGroupViewManager());
viewManagers.add(ARTRenderableViewManager.createARTShapeViewManager());
viewManagers.add(ARTRenderableViewManager.createARTTextViewManager());
viewManagers.add(new ARTSurfaceViewManager());
viewManagers.add(new ReactDialogPickerManager());
viewManagers.add(new ReactDrawerLayoutManager());
viewManagers.add(new ReactDropdownPickerManager());
viewManagers.add(new ReacthorizontalscrollviewManager());
viewManagers.add(new ReactimageManager());
viewManagers.add(new ReactModalHostManager());
viewManagers.add(new ReactProgressBarViewManager());
viewManagers.add(new ReactRawTextManager());
viewManagers.add(new ReactScrollViewManager());
viewManagers.add(new ReactSliderManager());
viewManagers.add(new ReactSwitchManager());
viewManagers.add(new FrescoBasedReactTextInlineImageViewManager());
viewManagers.add(new ReactTextInputManager());
viewManagers.add(new ReactTextViewManager());
viewManagers.add(new ReactToolbarManager());
viewManagers.add(new ReactViewManager());
viewManagers.add(new ReactViewPagerManager());
viewManagers.add(new ReactVirtualTextViewManager());
viewManagers.add(new ReactWebViewManager());
viewManagers.add(new SwipeRefreshLayoutManager());
SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(reactContext);
if (preferences.getBoolean("flat_uiimplementation",false)) {
viewManagers.addAll(Arrays.asList(
new RCTViewManager(),new RCTTextManager(),new RCTRawTextManager(),new RCTVirtualTextManager(),new RCTTextInlineImageManager(),new RCtimageViewManager(),new RCTTextInputManager(),new RCTViewPagerManager(),new FlatARTSurfaceViewManager(),new RCTModalHostManager()));
}
return viewManagers;
}
今天关于如何设计一个好用的 React Image 组件？和react组件设计原则的讲解已经结束，谢谢您的阅读，如果想了解更多关于Android 设计一个菱形形状的Imageview组件.、com.facebook.imagepipeline.image.CloseableAnimatedImage的实例源码、com.facebook.react.views.image.ImageResizeMode的实例源码、com.facebook.react.views.image.ReactImageManager的实例源码的相关知识，请在本站搜索。
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