Overview In HarmonyOS 5Ability development, there is significant room for optimizing image loading performance, especially the frustration caused by the lack of a retry mechanism after loading failures in poor network environments. This article introduces an optimized ImageReloadComponent for the Image component in HarmonyOS 5, which enhances image loading efficiency and reduces network consumption through technologies such as local caching, domain validation, and concurrency control. It effectively solves the problem of failed network image loading in the Image component.

I. Component Structure Analysis 1.1 Core Component: ImageReloadComponent @Component export struct ImageReloadComponent { // State management @State isOnError: boolean = false @Require @State @Watch('updateSrc') src: PixelMap | ResourceStr | DrawableDescriptor = ''

  // Image rendering parameters  
  @State objectFit: ImageFit = ImageFit.Cover  
  @State objectRepeat: ImageRepeat = ImageRepeat.NoRepeat  
  @State interpolation: ImageInterpolation = ImageInterpolation.Low  
  
  // Controller instance  
  imageReload: ImageReloadComController = new ImageReloadComController()  
 
  // Lifecycle method  
  async aboutToAppear(): Promise<void> {  
    if (typeof this.src === 'string') {  
      this.src = await this.imageReload.downloadImageToCache(this.src)  
    }  
  }  
 
  // Build method  
  build() {  
    Image(this.src)  
      .objectFit(this.objectFit)  
      .onComplete(() => this.onComplete())  
      .onError(() => this.onError())  
  }  

} Functional Features: Automatic Caching: Triggers image download and caching when the component mounts State Monitoring: Listens for src changes via the @Watch decorator Flexible Rendering: Supports configuration of 12+ image rendering parameters Event Callbacks: Provides complete lifecycle callbacks (onComplete/onError/onFinish) 1.2 Caching Controller: ImageReloadComController Class Inheritance Hierarchy:

AbstractImageCacheController └── ImageReloadComController Core Capability Matrix: FunctionImplementation MethodCache DownloadHTTP requests + local file storageConcurrency ControlPromise locking mechanismDomain ValidationURL parsing + domain whitelist checkCache ManagementFile system operationsTemporary File HandlingAtomic write + rename mechanism

II. Key Technical Implementations