PowerImage

A powerful plugin that fully uses the native image library's ability to display images on the flutter side.

Features:

Supports the ability to load ui.Image. In the solution based on external texture, the user could not get the real ui.Image to use, which made the image library powerless in this special usage scenario.
Support image preloading capability. Just like flutter precacheImage. This is very useful in some scenarios that require high image display speed.
Added texture cache to connect with flutter's imageCache! Unified image cache to avoid memory problems caused by mixing native images.
Emulators are supported. Before flutter-1.23.0-18.1.pre, the emulator could not display Texture Widget.
Improve the custom image type channel. Solve the demand for business custom image acquisition.
Perfect exception capture and collection.
Support animation.

Usage

Installation

power_image：It is recommended to use the latest version
power_image_ext：You need to choose the version based on the flutter version you are using. Go to power_image_ext for details！

Add the following to your pubspec.yaml file:

dependencies:
  power_image:
    git:
      url: 'git@github.com:alibaba/power_image.git'
      ref: '0.1.0'
      
dependency_overrides:
  power_image_ext:
    git:
      url: 'git@github.com:alibaba/power_image_ext.git'
      ref: '2.5.3'

Setup

Flutter

1. Replace `ImageCache` with `ImageCacheExt`.

/// call before runApp()
PowerImageBinding();

/// return ImageCacheExt in createImageCache(), 
/// if you have extends with WidgetsFlutterBinding
class XXX extends WidgetsFlutterBinding {
  @override
  ImageCache createImageCache() {
    return ImageCacheExt();
  }
}

2. Setup PowerImageLoader

Initialize and set the global default rendering mode, renderingTypeTexture is texture mode, renderingTypeExternal is ffi mode In addition, there are exception reports in PowerImageSetupOptions, and the sampling rate of exception reports can be set.

    PowerImageLoader.instance.setup(PowerImageSetupOptions(renderingTypeTexture,
        errorCallbackSamplingRate: 1.0,
        errorCallback: (PowerImageLoadException exception) {

    }));

iOS

PowerImage provides basic image types, including network, file, nativeAsset, and flutter assets. Users need to customize their corresponding loaders.

    [[PowerImageLoader sharedInstance] registerImageLoader:[PowerImageNetworkImageLoader new] forType:kPowerImageImageTypeNetwork];
    [[PowerImageLoader sharedInstance] registerImageLoader:[PowerImageAssetsImageLoader new] forType:kPowerImageImageTypeNativeAsset];
    [[PowerImageLoader sharedInstance] registerImageLoader:[PowerImageFlutterAssertImageLoader new] forType:kPowerImageImageTypeAsset];
    [[PowerImageLoader sharedInstance] registerImageLoader:[PowerImageFileImageLoader new] forType:kPowerImageImageTypeFile];

The loader needs to follow the PowerImageLoaderProtocol protocol:

typedef void(^PowerImageLoaderCompletionBlock)(BOOL success, PowerImageResult *imageResult);

@protocol PowerImageLoaderProtocol <NSObject>
@required
- (void)handleRequest:(PowerImageRequestConfig *)requestConfig completed:(PowerImageLoaderCompletionBlock)completedBlock;
@end

Network image loader example:

- (void)handleRequest:(PowerImageRequestConfig *)requestConfig completed:(PowerImageLoaderCompletionBlock)completedBlock {
    
    /// CDN optimization, you need transfer reqSize to native image loader!
    /// CDN optimization, you need transfer reqSize to native image loader!
    /// like this: [[SDWebImageManager sharedManager] downloadImageWithURL:[NSURL URLWithString:requestConfig.srcString] viewSize:reqSize completed:
    CGSize reqSize = requestConfig.originSize;
    /// attention.

    
    [[SDWebImageManager sharedManager] loadImageWithURL:[NSURL URLWithString:requestConfig.srcString] options:nil progress:^(NSInteger receivedSize, NSInteger expectedSize, NSURL * _Nullable targetURL) {

        } completed:^(UIImage * _Nullable image, NSData * _Nullable data, NSError * _Nullable error, SDImageCacheType cacheType, BOOL finished, NSURL * _Nullable imageURL) {
            if (image != nil) {
                completedBlock([PowerImageResult successWithImage:image]);
            }else {
                completedBlock([PowerImageResult failWithMessage:error.localizedDescription]);
            }
    }];

}

native asset loader example:

- (void)handleRequest:(PowerImageRequestConfig *)requestConfig completed:(PowerImageLoaderCompletionBlock)completedBlock {
    UIImage *image = [UIImage imageNamed:requestConfig.srcString];
    if (image) {
        completedBlock([PowerImageResult successWithImage:image]);
    }else {
        completedBlock([PowerImageResult failWithMessage:@"MyAssetsImageLoader UIImage imageNamed: nil"]);
    }
}

flutter asset loader example:

- (void)handleRequest:(PowerImageRequestConfig *)requestConfig completed:(PowerImageLoaderCompletionBlock)completedBlock {
    UIImage *image = [self flutterImageWithName:requestConfig];
    if (image) {
        completedBlock([PowerImageResult successWithImage:image]);
    } else {
        completedBlock([PowerImageResult failWithMessage:@"flutterImageWithName nil"]);
    }
}

- (UIImage*)flutterImageWithName:(PowerImageRequestConfig *)requestConfig {
    NSString *name = requestConfig.srcString;
    NSString *package = requestConfig.src[@"package"];
    NSString *filename = [name lastPathComponent];
    NSString *path = [name stringByDeletingLastPathComponent];
    for (int screenScale = [UIScreen mainScreen].scale; screenScale > 1; --screenScale) {
        NSString *key = [self lookupKeyForAsset:[NSString stringWithFormat:@"%@/%d.0x/%@", path, screenScale, filename] fromPackage:package];
        UIImage *image = [UIImage imageNamed:key inBundle:[NSBundle mainBundle] compatibleWithTraitCollection:nil];
        if (image) {
            return image;
        }
    }
    NSString *key = [self lookupKeyForAsset:name fromPackage:package];

    /// webp iOS < 14 not support 
    if ([name hasSuffix:@".webp"] && !(@available(ios 14.0, *))) {
        NSString *mPath = [[NSBundle mainBundle] pathForResource:key ofType:nil];
        NSData *webpData = [NSData dataWithContentsOfFile:mPath];
        return [UIImage sd_imageWithWebPData:webpData];
    }
    return [UIImage imageNamed:key inBundle:[NSBundle mainBundle] compatibleWithTraitCollection:nil];
}

- (NSString *)lookupKeyForAsset:(NSString *)asset fromPackage:(NSString *)package {
    if (package && [package isKindOfClass:[NSString class]] && ![package isEqualToString:@""]) {
        return [FlutterDartProject lookupKeyForAsset:asset fromPackage:package];
    }else {
        return [FlutterDartProject lookupKeyForAsset:asset];
    }
}

file loader example:

- (void)handleRequest:(PowerImageRequestConfig *)requestConfig completed:(PowerImageLoaderCompletionBlock)completedBlock {
    
    UIImage *image = [[UIImage alloc] initWithContentsOfFile:requestConfig.srcString];

    if (image) {
        completedBlock([PowerImageResult successWithImage:image]);
    } else {
        completedBlock([PowerImageResult failWithMessage:@"UIImage initWithContentsOfFile nil"]);
    }
}

Android

PowerImage provides basic image types, including network, file, nativeAsset, and flutter assets. Users need to customize their corresponding loaders.

PowerImageLoader.getInstance().registerImageLoader(
                new PowerImageNetworkLoader(this.getApplicationContext()), "network");
PowerImageLoader.getInstance().registerImageLoader(
                new PowerImageNativeAssetLoader(this.getApplicationContext()), "nativeAsset");
PowerImageLoader.getInstance().registerImageLoader(
                new PowerImageFlutterAssetLoader(this.getApplicationContext()), "asset");
PowerImageLoader.getInstance().registerImageLoader(
                new PowerImageFileLoader(this.getApplicationContext()), "file");

The loader needs to follow the PowerImageLoaderProtocol protocol:

public interface PowerImageLoaderProtocol {
    void handleRequest(PowerImageRequestConfig request, PowerImageResult result);
}

Network image loader example:

@Override
public void handleRequest(PowerImageRequestConfig request, PowerImageResult result) {
    Glide.with(context).load(request.srcString()).into(new CustomTarget<Drawable>(
        request.width <= 0 ? Target.SIZE_ORIGINAL : request.width,
        request.height <= 0 ? Target.SIZE_ORIGINAL : request.height){

        @Override
        public void onResourceReady(@NonNull Drawable resource, @Nullable Transition<? super Drawable> transition) {
            if (resource instanceof BitmapDrawable) {
                BitmapDrawable bitmapDrawable = (BitmapDrawable)resource;
                result.onResult(true, bitmapDrawable.getBitmap());
            } else if (resource instanceof GifDrawable) {
                result.onResult(true, ((GifDrawable) resource).getFirstFrame());
            } else {
                result.onResult(false, null);
            }
        }

        @Override
        public void onLoadFailed(@Nullable Drawable errorDrawable) {
            super.onLoadFailed(errorDrawable);
            result.onResult(false, null);
        }

        @Override
        public void onLoadCleared(@Nullable Drawable placeholder) {

        }
    });
}

native asset loader example:

@Override
public void handleRequest(PowerImageRequestConfig request, PowerImageResult result) {
    Resources resources = context.getResources();
    int resourceId = 0;
    try {
        resourceId = resources.getIdentifier(request.srcString(),
                                             "drawable", context.getPackageName());
    } catch (Resources.NotFoundException e) {
        // 资源未找到
        e.printStackTrace();
    }
    if (resourceId == 0) {
        result.onResult(false, null);
        return;
    }
    Glide.with(context).load(resourceId).into(
        new CustomTarget<Drawable>(request.width <= 0 ? Target.SIZE_ORIGINAL : request.width,
                                   request.height <= 0 ? Target.SIZE_ORIGINAL : request.height) {
            @Override
            public void onResourceReady(@NonNull Drawable resource,
                                        @Nullable Transition<? super Drawable> transition) {
                if (resource instanceof BitmapDrawable) {
                    BitmapDrawable bitmapDrawable = (BitmapDrawable) resource;
                    result.onResult(true, bitmapDrawable.getBitmap());
                } else {
                    result.onResult(false, null);
                }
            }

            @Override
            public void onLoadFailed(@Nullable Drawable errorDrawable) {
                super.onLoadFailed(errorDrawable);
                result.onResult(false, null);
            }

            @Override
            public void onLoadCleared(@Nullable Drawable placeholder) {

            }
        });
}

flutter asset loader example:

@Override
public void handleRequest(PowerImageRequestConfig request, PowerImageResult result) {
    String name = request.srcString();
    if (name == null || name.length() <= 0) {
        result.onResult(false, null);
        return;
    }
    String assetPackage = "";
    if (request.src != null) {
        assetPackage = (String) request.src.get("package");
    }
    String path;
    if (assetPackage != null && assetPackage.length() > 0) {
        path = FlutterMain.getLookupKeyForAsset(name, assetPackage);
    } else {
        path = FlutterMain.getLookupKeyForAsset(name);
    }
    if (path == null || path.length() <= 0) {
        result.onResult(false, null);
        return;
    }
    Uri asset = Uri.parse("file:///android_asset/" + path);
    Glide.with(context).load(asset).into(
        new CustomTarget<Drawable>(request.width <= 0 ? Target.SIZE_ORIGINAL : request.width,
                                   request.height <= 0 ? Target.SIZE_ORIGINAL : request.height) {
            @Override
            public void onResourceReady(@NonNull Drawable resource,
                                        @Nullable Transition<? super Drawable> transition) {
                if (resource instanceof BitmapDrawable) {
                    BitmapDrawable bitmapDrawable = (BitmapDrawable) resource;
                    result.onResult(true, bitmapDrawable.getBitmap());
                } else if (resource instanceof GifDrawable) {
                    result.onResult(true, ((GifDrawable) resource).getFirstFrame());
                }
            }

            @Override
            public void onLoadCleared(@Nullable Drawable placeholder) {

            }

            @Override
            public void onLoadFailed(@Nullable Drawable errorDrawable) {
                super.onLoadFailed(errorDrawable);
                result.onResult(false, null);
            }
        });
}

file loader example:

@Override
public void handleRequest(PowerImageRequestConfig request, PowerImageResult result) {
    String name = request.srcString();
    if (name == null || name.length() <= 0) {
        result.onResult(false, null);
        return;
    }
    Uri asset = Uri.parse("file://" + name);
    Glide.with(context).load(asset).into(
        new CustomTarget<Drawable>(request.width <= 0 ? Target.SIZE_ORIGINAL : request.width,
                                   request.height <= 0 ? Target.SIZE_ORIGINAL : request.height) {
            @Override
            public void onResourceReady(@NonNull Drawable resource,
                                        @Nullable Transition<? super Drawable> transition) {
                if (resource instanceof BitmapDrawable) {
                    BitmapDrawable bitmapDrawable = (BitmapDrawable) resource;
                    result.onResult(true, bitmapDrawable.getBitmap());
                } else if (resource instanceof GifDrawable) {
                    result.onResult(true, ((GifDrawable) resource).getFirstFrame());
                }
            }

            @Override
            public void onLoadCleared(@Nullable Drawable placeholder) {

            }

            @Override
            public void onLoadFailed(@Nullable Drawable errorDrawable) {
                super.onLoadFailed(errorDrawable);
                result.onResult(false, null);
            }
        });
}

API

network image:

  PowerImage.network(
    String src, {
    Key? key,
    String? renderingType,
    double? imageWidth,
    double? imageHeight,
    this.width,
    this.height,
    this.frameBuilder,
    this.errorBuilder,
    this.fit = BoxFit.cover,
    this.alignment = Alignment.center,
    this.semanticLabel,
    this.excludeFromSemantics = false,
  })

nativeAsset:

PowerImage.nativeAsset(
    String src, {
    Key? key,
    String? renderingType,
    double? imageWidth,
    double? imageHeight,
    this.width,
    this.height,
    this.frameBuilder,
    this.errorBuilder,
    this.fit = BoxFit.cover,
    this.alignment = Alignment.center,
    this.semanticLabel,
    this.excludeFromSemantics = false,
  })

Flutter asset:

  PowerImage.asset(
    String src, {
    Key? key,
    String? renderingType,
    double? imageWidth,
    double? imageHeight,
    String? package,
    this.width,
    this.height,
    this.frameBuilder,
    this.errorBuilder,
    this.fit = BoxFit.cover,
    this.alignment = Alignment.center,
    this.semanticLabel,
    this.excludeFromSemantics = false,
  })

File:

  PowerImage.file(String src,
      {Key key,
      this.width,
      this.height,
      this.frameBuilder,
      this.errorBuilder,
      this.fit = BoxFit.cover,
      this.alignment = Alignment.center,
      String renderingType,
      double imageWidth,
      double imageHeight})

Custom Image Type:

  /// 自定义 imageType\src
  /// 效果：将src encode 后，完成地传递给 native 对应 imageType 注册的 loader
  /// 使用场景：
  /// 例如，自定义加载相册照片，通过自定义 imageType 为 "album"，
  /// native 侧注册 "album" 类型的 loader 自定义图片的加载。  
PowerImage.type(
    String imageType, {
    required PowerImageRequestOptionsSrc src,
    Key? key,
    String? renderingType,
    double? imageWidth,
    double? imageHeight,
    this.width,
    this.height,
    this.frameBuilder,
    this.errorBuilder,
    this.fit = BoxFit.cover,
    this.alignment = Alignment.center,
    this.semanticLabel,
    this.excludeFromSemantics = false,
  })

.options

  /// 更加灵活的方式，通过自定义options来展示图片
  ///
  /// PowerImageRequestOptions({
  ///   @required this.src,   //资源
  ///   @required this.imageType, //资源类型，如网络图，本地图或者自定义等
  ///   this.renderingType, //渲染方式，默认全局
  ///   this.imageWidth,  //图片的渲染的宽度
  ///   this.imageHeight, //图片渲染的高度
  /// });
  ///
  /// PowerExternalImageProvider（FFI[bitmap]方案）
  /// PowerTextureImageProvider（texture方案）
  ///
  /// 使用场景：
  /// 例如，自定义加载相册照片，通过自定义 imageType 为 "album"，
  /// native 侧注册 "album" 类型的 loader 自定义图片的加载。
  ///
PowerImage.options(
    PowerImageRequestOptions options, {
    Key? key,
    this.width,
    this.height,
    this.frameBuilder,
    this.errorBuilder,
    this.fit = BoxFit.cover,
    this.alignment = Alignment.center,
    this.semanticLabel,
    this.excludeFromSemantics = false,
  })

Example

Network

          return PowerImage.network(
            'https://flutter.github.io/assets-for-api-docs/assets/widgets/owl.jpg',
            width: 100,
            height: 100,
          );

Best practice

How it works

https://mp.weixin.qq.com/s/TdTGK21S-Yd3aD-yZDoYyQ

allenymt/power_image