垫树不会自动关闭子级

Question

我使用来自https://material.angular.io/components/tree/examples的动态数据修改了树中的代码。

它可以加载数据，但是当我关闭父节点而不关闭子节点时，它无法正常工作。

我不知道我在做什么错。在文档的示例中，它从头到尾分别关闭每个级别。但是我没有。

这是我的代码：

import { Component, OnInit, Injectable } from '@angular/core';
import { FlatTreeControl } from '@angular/cdk/tree';
import { CollectionViewer, SelectionChange } from '@angular/cdk/collections';
import { BehaviorSubject, Observable, merge } from 'rxjs';
import { CatalogoBean, FilterBean } from '../../../common/rest/services/Beans';
import { map } from 'rxjs/operators';
import { ClasificacionControllerNg } from '../../../common/rest/services/ClasificacionControllerNg';
import { MatTreeFlatDataSource } from '@angular/material/tree';

export class FlatNode {
  constructor(public catalogo: CatalogoBean,
    public level: number = 1, public expandable: boolean = catalogo.hijos,
    public isLoading?: boolean) { }
}

@Injectable({ providedIn: 'root' })
export class DynamicDataBase {
  constructor(private clasificacionController: ClasificacionControllerNg) {
  }

  initialData(): Observable<any> {
    const filterBean = {
      inicio: 0,
      maximo: 0,
      direccion: '',
      sort: undefined,
      id: 0,
    } as FilterBean;
    return this.clasificacionController.listCatalogo(filterBean);
  }


  getChildren(node: CatalogoBean): Observable<any> {
    const filterBean = {
      inicio: 0,
      maximo: 0,
      direccion: '',
      sort: undefined,
      id: node.idcatalogo,
    } as FilterBean;
    return this.clasificacionController.listCatalogo(filterBean);
  }

  isExpandable(node: CatalogoBean): boolean {
    return node.hijos;
  }
}

export class DynamicDataSource {
  dataChange: BehaviorSubject<FlatNode[]> = new BehaviorSubject<FlatNode[]>([]);

  get data(): FlatNode[] {
    return this.dataChange.value;
  }
  set data(value: FlatNode[]) {
    this.treeControl.dataNodes = value;
    this.dataChange.next(value);
  }

  constructor(private treeControl: FlatTreeControl<FlatNode>,
    private database: DynamicDataBase) {
  }

  disconnect(collectionViewer: CollectionViewer): void {
  }

  connect(collectionViewer: CollectionViewer): Observable<FlatNode[]> {
    this.treeControl.expansionModel.changed.subscribe(change => {
      if ((change as SelectionChange<FlatNode>).added ||
        (change as SelectionChange<FlatNode>).removed) {
        this.handleTreeControl(change as SelectionChange<FlatNode>);
      }
    });

    return merge(collectionViewer.viewChange, this.dataChange).pipe(map((node) => this.data));
  }

  handleTreeControl(change: SelectionChange<FlatNode>) {
    if (change.added) {
      change.added.forEach(node => this.toggleNode(node, true));
    }
    if (change.removed) {
      change.removed.reverse().forEach((node) => this.toggleNode(node, false));
    }
  }

  toggleNode(node: FlatNode, expand: boolean) {
    const index = this.data.indexOf(node);
    let children: Array<CatalogoBean>;

    if (!node.catalogo.hijos || index < 0) { // If no children, or cannot find the node, no op
      return;
    } else {
      this.database.getChildren(node.catalogo).subscribe((catalogos: Array<CatalogoBean>) => {
        children = catalogos.filter(catalogo => catalogo.idcatalogo !== -1);
        if (expand) {
          node.isLoading = true;
          const nodes = children.map(catalogo =>
            new FlatNode(catalogo, node.level + 1, this.database.isExpandable(catalogo), false));
          this.data.splice(index + 1, 0, ...nodes);
          // notify the change
          this.dataChange.next(this.data);
          node.isLoading = false;
        } else { // CERRADO
          this.data.splice(index + 1, children.length);
          this.dataChange.next(this.data);
        }
      });
    }
  }

}

@Component({
  selector: 'app-tree-example',
  templateUrl: './tree-example.component.html',
  styleUrls: ['./tree-example.component.css'],
})
export class TreeExampleComponent {

  treeControl: FlatTreeControl<FlatNode>;

  dataSource: DynamicDataSource;

  getLevel = (node: FlatNode) => node.level;

  isExpandable = (node: FlatNode) => node.expandable;

  hasChild = (_: number, _nodeData: FlatNode) => _nodeData.expandable;

  constructor(private clasificacionController: ClasificacionControllerNg, database: DynamicDataBase) {
    this.treeControl = new FlatTreeControl<FlatNode>(this.getLevel, this.isExpandable);
    this.dataSource = new DynamicDataSource(this.treeControl, database);
    database.initialData().subscribe((catalogos: Array<CatalogoBean>) => {
      catalogos = catalogos.filter(catalogo => catalogo.idcatalogo !== -1);
      this.dataSource.data = catalogos.map(node => new FlatNode(node, 0, node.hijos, false));
    });
  }
}

我们非常感谢您的帮助。