显示/隐藏多个 div 取决于屏幕角度 2

Question

我想使用一些按钮来使用 angular2 显示/隐藏多个 div

页面最初会显示所有 div。当小屏幕时，我隐藏所有 div，然后单独的按钮显示特定的 div，同时隐藏其余部分。

任何帮助将不胜感激。

<div class="buttons">
<a class="button" id="showdiv1">Div 1</a>
<a class="button" id="showdiv2">Div 2</a>
<a class="button" id="showdiv3">Div 3</a>
</div>


<div class="row">
  <div class="col-xlg-4 col-xl-5 col-lg-12 col-sm-12 col-xs-12 hidden-sm-down">
  </div>

   <div class="col-xlg-4 col-xl-5 col-lg-12 col-sm-12 col-xs-12 hidden-sm-down">
  </div>

   <div class="col-xlg-4 col-xl-5 col-lg-12 col-sm-12 col-xs-12 hidden-sm-down">
  </div>
</div>

Answer 1

使用@HostListener 和resize 事件来确定视口的宽度。然后在您的组件中设置一个具有此值的属性，然后您可以将其提供给 HTML 模板中的ngIf*。

import { Component, HostListener, AfterViewInit } from '@angular/core';

@Component()

export class AppComponent { 

  windowWidth: number = window.innerWidth;

  //initial values, The window object may still be undefined during this hook, let me know if that's the case and we'll figure out a better hook for the initial value
  ngAfterViewInit() {
      this.windowWidth = window.innerWidth;
  }

  //if screen size changes it'll update
  @HostListener('window:resize', ['$event'])
  resize(event) {
      this.windowWidth = window.innerWidth;
  }

}

<!-- Then any HTML element you wish to toggle apply the *ngIf directive as so: -->

<div *ngIf*="windowWidth > 800">content</div>