HarmonyOS 鸿蒙Next WaterFlow瀑布流用LazyForEach懒加载的数组怎么清空

可以试一下如下方法：

清除dataArray中的数据：

class BasicDataSource <T> implements IDataSource {
  private listeners: DataChangeListener[] = [];
public totalCount(): number {
return 0;
}
public getData(index: number): T | undefined {
return undefined;
}
// 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) {
this.listeners.push(listener);
}
}
// 该方法为框架侧调用，为LazyForEach组件向其数据源处添加listener监听
unregisterDataChangeListener(listener: DataChangeListener): void {
const pos = this.listeners.indexOf(listener);
if (pos >= 0) {
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);
})
}
// 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);
})
}
// 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);
})
}
// 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);
})
}
}
@Observed
export default class LazyDataSource<T> extends BasicDataSource<T> {
dataArray: T[] = [];
public totalCount(): number {
return this.dataArray.length;
}
//获取某一项
public getData(index: number): T {
return this.dataArray[index];
}
//根据索引添加数据
public addData(index: number, data: T): void {
this.dataArray.splice(index, 0, data);
this.notifyDataAdd(index);
}
//列表尾部添加数据
public pushData(data: T): void {
this.dataArray.push(data);
this.notifyDataAdd(this.dataArray.length - 1);
}
//刷新数据–一页
public refreshData(newData: T[]): void {
this.dataArray = []
newData.forEach(element => {
this.pushData(element)
});
this.notifyDataReload();
}
//获取数据–多页
public getAllData(newData: T[]): void {
this.dataArray = […this.dataArray,…newData]
this.notifyDataReload();
}
//删除
public deleteData(index: number): void {
this.dataArray.splice(index, 1);
this.notifyDataDelete(index);
}
//获取列表数据
public getDataList(): T[] {
return this.dataArray;
}
//删除全部数据
public clear(): void {
this.empty()
this.refresh()
}
public empty(): void {
this.dataArray = []
}
public refresh(): void {
this.notifyDataReload();
}
}