
    <nz-tree-select
      style="width: 250px"
      nzPlaceHolder="Please select"
      [nzExpandedKeys]="expandKeys"
      [(ngModel)]="value"
      [nzDropdownMatchSelectWidth]="true"
      [nzDropdownStyle]="{ 'max-height': '300px' }"
      [nzNodes]="nodes"
      [nzAsyncData]="true"
      (nzExpandChange)="onExpandChange($event)"
    ></nz-tree-select>
  