HarmonyOS 鸿蒙Next LazyForEach + Lottie动画 内存占用过大

HarmonyOS 鸿蒙Next LazyForEach + Lottie动画 内存占用过大
参考 [如何定位列表中Canvas加载Lottie动画卡顿的问题-测试与调优-常见问题手册 - 华为HarmonyOS开发者 (huawei.com)] 编码。

用profiler观察滑动时的实时内存变化，发现内存占用过大。搞不清楚是代码原因还是GC不足。

根据官方文档编写如下两个文件代码于pages目录，lottie动画路径请自行添加：

//Index.ets

/**
* BasicDataSource代码见文档末尾附件: string类型数组的BasicDataSource代码
*/
import { NineListItem } from './NineListItem';

// BasicDataSource实现了IDataSource接口，用于管理listener监听，以及通知LazyForEach数据更新
class BasicDataSource implements IDataSource {
  private listeners: DataChangeListener[] = [];
  private originDataArray: string[] = [];

  public totalCount(): number {
    return 0;
  }

  public getData(index: number): string {
    return this.originDataArray[index];
  }

  // 该方法为框架侧调用，为LazyForEach组件向其数据源处添加listener监听
  registerDataChangeListener(listener: DataChangeListener): void {
    if (this.listeners.indexOf(listener) < 0) {
      console.info('add listener');
      this.listeners.push(listener);
    }
  }

  // 该方法为框架侧调用，为对应的LazyForEach组件在数据源处去除listener监听
  unregisterDataChangeListener(listener: DataChangeListener): void {
    const pos = this.listeners.indexOf(listener);
    if (pos >= 0) {
      console.info('remove listener');
      this.listeners.splice(pos, 1);
    }
  }

  // 通知LazyForEach组件需要重载所有子组件
  notifyDataReload(): void {
    this.listeners.forEach(listener => {
      listener.onDataReloaded();
    })
  }

  // 通知LazyForEach组件需要在index对应索引处添加子组件
  notifyDataAdd(index: number): void {
    this.listeners.forEach(listener => {
      listener.onDataAdd(index);
      // 写法2：listener.onDatasetChange([{type: DataOperationType.ADD, index: index}]);
    })
  }

  // 通知LazyForEach组件在index对应索引处数据有变化，需要重建该子组件
  notifyDataChange(index: number): void {
    this.listeners.forEach(listener => {
      listener.onDataChange(index);
      // 写法2：listener.onDatasetChange([{type: DataOperationType.CHANGE, index: index}]);
    })
  }

  // 通知LazyForEach组件需要在index对应索引处删除该子组件
  notifyDataDelete(index: number): void {
    this.listeners.forEach(listener => {
      listener.onDataDelete(index);
      // 写法2：listener.onDatasetChange([{type: DataOperationType.DELETE, index: index}]);
    })
  }

  // 通知LazyForEach组件将from索引和to索引处的子组件进行交换
  notifyDataMove(from: number, to: number): void {
    this.listeners.forEach(listener => {
      listener.onDataMove(from, to);
      // 写法2：listener.onDatasetChange(
      //         [{type: DataOperationType.EXCHANGE, index: {start: from, end: to}});
    })
  }

  notifyDatasetChange(operations: DataOperation[]): void {
    this.listeners.forEach(listener => {
      listener.onDatasetChange(operations);
    })
  }
}

class MyDataSource extends BasicDataSource {
  private dataArray: string[] = [];

  public totalCount(): number {
    return this.dataArray.length;
  }

  public getData(index: number): string {
    return this.dataArray[index];
  }

  public pushData(data: string): void {
    this.dataArray.push(data);
    this.notifyDataAdd(this.dataArray.length - 1);
  }
}

declare class ArkTools {
  static hintGC(): void;
}

@Entry
@Component
struct MyComponent {
  private data: MyDataSource = new MyDataSource();

  aboutToAppear() {
    for (let i = 0; i <= 50; i++) {
      this.data.pushData(`Hello ${i}`)
    }
  }

  build() {

    Column(){
      Button("触发HintGC").onClick((event: ClickEvent) => {
      ArkTools.hintGC();  //方法内直接调用
    })

      List({ space: 3 }) {
        LazyForEach(this.data, (item: string) => {

          NineListItem({index:item})

        }, (item: string) => item)
      }.cachedCount(2)
    }


  }
}

//NineListItem.ets

import Lottie, { AnimationItem } from '@ohos/lottie'

@Reusable
@Component
export struct NineListItem {
  @State @Require index: string = 'a';
  @State isPlaying: boolean = false;
  private mainRenderingSettings: RenderingContextSettings = new RenderingContextSettings(true)
  private mainCanvasRenderingContext: CanvasRenderingContext2D =
    new CanvasRenderingContext2D(this.mainRenderingSettings)
  private animateName: string = "homeLiveFeedAnimate" + (Math.random() * 1000).toFixed()

  private animateItem: AnimationItem | null = null;

  aboutToDisappear(): void {
    // 组件销毁时先释放动画对象
    this.animateItem?.destroy();
    this.animateItem = null;
    Lottie.destroy(this.animateName)
  }

  build() {
    Row() {

            Canvas(this.mainCanvasRenderingContext)
              .width(200)
              .height(200)
              .backgroundColor(Color.Gray)
              .onReady(() => {
                this.animateItem?.destroy();
                // 加载动画
                if (this.animateItem != null) {
                  // 可在此生命回调周期中加载动画，可以保证动画尺寸正确
                  this.animateItem?.resize();
                } else {
                  // 抗锯齿的设置
                  this.mainCanvasRenderingContext.imageSmoothingEnabled = true;
                  this.mainCanvasRenderingContext.imageSmoothingQuality = 'medium'
                  this.animateItem = Lottie.loadAnimation({
                    container: this.mainCanvasRenderingContext,
                    renderer: 'canvas', // canvas 渲染模式
                    loop: true,
                    autoplay: false,
                    name: this.animateName,
                    contentMode: 'Contain',
                    path: "pages/lottie/animation.json",
                  })
                  this.animateItem.changeColor([225, 25, 100, 1]);
                  this.animateItem.play()
                }})
      Text("Hello!!")


    }
  }
}