问向下滚动时自动隐藏角度材质工具栏(顶部导航栏)

EN

.exemple-toolbar {
  position: sticky;
  top: -200px;
  padding-top: 200px;
  height: 250px;
}

scrollTop = 0;
hideNav = false;

onScroll(event) {
  this.hideNav = this.scrollTop < event.target.scrollTop;
  this.scrollTop = event.target.scrollTop;
}

.container {
  height: 100vh;
  overflow-y: scroll;
  overflow-x: hidden;
}

.nav {
  position: fixed;
  height: 50px;
  display: flex;
}

.nav.hide-nav {
  display: none; /* You can play on opacity for nice transitions*/
}

<div class="container" (scroll)="onScroll($event)">

  <div class="nav" [class.hide-nav]="hideNav">
     <!-- Nav -->
  </div>

<!--content-->

</div>