HarmonyOS 设置沉浸式后在任务列表界面，应用的顶部显示白色

只需要在页面容器加上.expandSafeArea([SafeAreaType.SYSTEM], [SafeAreaEdge.TOP, SafeAreaEdge.BOTTOM])即可，请参考文档：https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/ts-universal-attributes-expand-safe-area-V5#expandsafearea

参考示例：

import { mStatusBarManagerInstance } from '../util/StatusBarManager';
import { router, window } from '@kit.ArkUI';

@Entry
@Component
struct Index {
  @State message: string = 'Hello World';
  @State statusBarHeight: number = 0;

  aboutToAppear(): void {

  }

  enabledImmersive: boolean = false;
  @State name: string = '开启沉浸式'

  build() {
    RelativeContainer() {
      Text(this.message)
        .id('HelloWorld')
        .fontSize(50)
        .fontWeight(FontWeight.Bold)
        .alignRules({
          center: { anchor: '__container__', align: VerticalAlign.Center },
          middle: { anchor: '__container__', align: HorizontalAlign.Center }
        })
        .onClick(() => {
          router.pushUrl({
            url: 'pages/DetailPage'
          })
        })
      Button(this.name).onClick((event) => {
        this.enabledImmersive = !this.enabledImmersive;

        if (this.enabledImmersive) {

        } else {

        }
      }).alignRules({
        center: { anchor: 'HelloWorld', align: VerticalAlign.Bottom },
        middle: { anchor: '__container__', align: HorizontalAlign.Center }
      }).margin({ top: 50 })
    }
    .backgroundColor(0x18cbbb)
    .height('100%')
    .width('100%')
    .margin({ top: this.statusBarHeight })

    .expandSafeArea([SafeAreaType.SYSTEM], [SafeAreaEdge.TOP, SafeAreaEdge.BOTTOM])
  }
}