在Angular中单击时显示/隐藏<ul>

Question

我正在尝试在HTML上显示菜单。目前它显示所有子菜单选项。我希望它显示所点击项目的选项。

以下是我的home.html代码

  <ul class="navbar-nav">
    <li data-toggle="dropdown" class="nav-item" *ngFor="let page of list;let i = index" id="id{{page.link_id}}"><span  (click)="showsubmenu(i)">{{page.link_name}}<i class="iconn" *ngIf="page.flg[0].SHOW_ICON=='YES'"><ion-icon name="md-arrow-dropdown"></ion-icon></i></span>

     <ul *ngFor="let sublink of page.sublink; let j=index;"><li >{{sublink.SUBLINK_NAME}}</li></ul>


    </li>
  </ul>

默认情况下，子菜单选项即将推出，请参见下面的屏幕截图：

下面的

home.ts代码：

export class HomePage {

 list = [];submenu;
  json_data = [
    {"link_id":"38","link_name":"Contact","flg":[{"SHOW_ICON":"NO"}],"sublink":[]},
    {"link_id":"37","link_name":"Offices","flg":[{"SHOW_ICON":"YES"}],"sublink":[{"SUBLINK_NAME":"test11","SUBLINK_OF":"37","SUBLINK_ID":"10005"}]},
    {"link_id":"34","link_name":"Products","flg":[{"SHOW_ICON":"YES"}],"sublink":[{"SUBLINK_NAME":"Quick Patrol","SUBLINK_OF":"34","SUBLINK_ID":"10004"},{"SUBLINK_NAME":"Link2","SUBLINK_OF":"34","SUBLINK_ID":"10013"}]},
    {"link_id":"33","link_name":"Home","flg":[{"SHOW_ICON":"NO"}],"sublink":[]}
  ];

  constructor(public navCtrl: NavController) {
this.list = this.json_data;
  }


  showsubmenu(index){

    this.submenu= this.list[index]["link_id"];
    console.log(this.submenu);
    this.submenu=this.list[index]["sublink"];
    console.log(this.submenu.length);

  }
}

Answer 1

引入一个新属性，该属性将保留打开的菜单索引。使用ngIf切换显示/隐藏子菜单：

<强> HTML：

//First li
<li (click)="show === i ? show =- 1: show = i" ....>

//second li
<li *ngIf="show === i">....

<强>打字稿：

...
show = -1;
...

DEMO

Answer 2

<ng-container *ngIf="page.flg[0]=='NO'?null:true"><ul *ngFor="let sublink of page.sublink; let j=index;"><li >{{sublink.SUBLINK_NAME}}</li></ul></ng-container>

在* .ts中，您可以添加

showsubmenu(index) { this.list[index]['flg'][0] === 'NO'? 'YES' : 'NO'; }

如果你将'flg'键保持为布尔值而不是字符串数组会更好。而不是'showsubmenu（）'，你可以在html本身处理flg键值，如：

(click)="page.flg?null:true"