HarmonyOS List的item中的某个字段改变之后如何刷新页面展示

可以使用@State和@Observed， 父组件和Entry中调用的组件建立双向连接，这样就可以实现数据的局部刷新了，Demo如下：

@Component
struct Child {
  @Link items: TestList[];
  build() {
    Column() {
      ForEach(this.items, (item: TestList) => {
        ChildChild({ item: item });
      })
      Button(`Button: push`).onClick(() => {
        this.items[0].index1 = 3;
        this.items[0].str = 'Third';
      })
    }
  }
}

@Component
struct ChildChild {
  @State item: TestList = new TestList();
  build() {
    Column() {
      Text(`${this.item.index1}+'-----'${this.item.str}`)
    }
  }
}
@Entry
@Component
struct Parent {
  @State arr: TestList[] = [];
  aboutToAppear() {
    let test1: TestList = new TestList();
    test1.index1 = 1;
    test1.str = 'First';
    this.arr.push(test1)
    let test2: TestList = new TestList();
    test2.index1 = 2;
    test2.str = 'Second';
    this.arr.push(test2)
  }
  build() {
    Column() {
      Child({ items: this.arr })
      Button(`Button: push`).onClick(() => {
        this.arr[1].index1 = 4;
        this.arr[1].str = 'Fourth';
      })
    }
  }
}
@Observed
class TestList {
  index1: number = 0;
  str: string = '';
}