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交互呈现

比如说我点击leaf 1-1-1的话  这个tree自动把leaf 1-1-1滚动到可视区域

实现方法

我是拿tree外层的div，设置ocerflow auto的，让外层div进行滚动，让选择元素呈现再可视区

1、滚动div已经确定

2、要拿取到选择元素在页面上的位置，也就是距离顶部的的距离，offsetTop，取offsetTop的时候会发现，选择元素的offsetTop拿取不到，那我们可以考虑拿取相邻的offsetTop，然后再减去相邻元素的自身高度就可以了

3、在选择元素进行滚动定位的过程中，会发现要取唯一值，直接查看dom发现只能取到titile，这个不是唯一值，所以要给dom添加key作为唯一值

上代码

 <div #treeContainer style="height: 200px; overflow-y: auto">
          <nz-tree
            [nzData]="catalogueNodes"
            #TreeComponent
            nzBlockNode
            [nzTreeTemplate]="nzTreeTemplate"
            (nzClick)="onCatalogueClick($event)"
            [nzSelectedKeys]="defaultSelectedKeys"
            [nzExpandedKeys]="defaultExpandedKeys"
          >
          </nz-tree>
          <ng-template #nzTreeTemplate let-node let-origin="origin">
            <div style="display: flex; justify-content: space-between" class="tree-node" [attr.rowKey]="node.key">
              <div>{{ node.title }}</div>
              <div class="node-bt" *ngIf="!node.isDisabled">
                <button nz-button nzType="primaryText" (click)="onBtnDeleteCatalogueClick($event, node)"
                  ><i nz-icon nzType="delete" nzTheme="outline"></i
                ></button>
              </div>
            </div>
          </ng-template>
        </div>

  @ViewChild('treeContainer') treeContainer!: ElementRef;
@ViewChild('TreeComponent') treeComponent!: NzTreeComponent;

  scrollKnowledge(key: string) {
    // 展开对应的父节点 
    let tmpNodeKey = this.treeComponent.getTreeNodeByKey('10021')?.parentNode?.key;
    if (!tmpNodeKey) tmpNodeKey = key;
    this.catalogueNodes = [...this.expandNodeData(this.catalogueNodes, tmpNodeKey!)];

    let ele = this.treeContainer.nativeElement.querySelector(
      `.ant-tree-treenode nz-tree-node-title .tree-node[rowKey='${10021}']`
    );
// ele.parentNode.parentNode.nextElementSibling    父亲节点父亲节点的相邻节点
    let offsetTop =
      ele.parentNode.parentNode.nextElementSibling.offsetTop -
      ele.parentNode.parentNode.nextElementSibling.offsetHeight * 1;

    this.treeContainer.nativeElement.scrollTo(0, offsetTop);
  }

  /**
   * 展开指定节点
   * @param data NzTreeNodeOptions[]
   * @param key string
   * @returns NzTreeNodeOptions[]
   */
  expandNodeData(data: NzTreeNodeOptions[], key: string): NzTreeNodeOptions[] {
    for (let i = 0; i < data.length; i++) {
      if (data[i].key === key) {
        data[i].expanded = true;
        break;
      }
      if (data[i].children) {
        this.expandNodeData(data[i].children!, key);
      }
    }
    return data;
  }

我这里数据写死掉了   你们可以用传进来的key去对应