如何用角度子列表?

• 1个
• 2个

<mat-sidenav-container fxFlex>
  <mat-sidenav mode="side" opened>
    <mat-tab-group>
      <mat-tab label="case 1">
        <mat-nav-list>
          <mat-list-item *ngFor="let step of case 1" (click)="selectedStep = step">
            <mat-icon matListAvatar svgIcon="icons:{{step.icon}}" class="avatar"></mat-icon>
            <span>{{step.name}}</span>
          </mat-list-item>
        </mat-nav-list>
      </mat-tab>
    </mat-tab-group>
  </mat-sidenav>

但是

• 1个
  • 1.2款
• • 2.1款
  • 2.2款
  • 2.3款