javascript - JS/jQuery - 将侧导航栏的滚动条设置到特定位置

Question

我有一个侧边导航栏，看起来像这样:

.scroll-box {
  overflow: hidden;
  width: 128px;
}
.filler {
  height: 256px;
  overflow-y: auto;
}
.selector {
  background-color: #369;
  padding: 8px 4px;
  text-align: center;
  flex-grow: 1;
  display: inline-block;
  cursor: pointer;
  box-sizing: border-box;
  transition: .1s !important;
}
.bar {
  height: 8px;
  width: 100%;
  background-color: #808080;
}
.label {
  padding: 4px 8px;
  background-color: #707070;
}
.active {
  background-color: lightgrey;
  color: #369;
}

<div class="scroll-box">
  <div class="label">Dates</div>
  <div class="filler">
    <div class="selector">4-Aug-16</div>
    <div class="selector">4-Aug-16</div>
    <div class="selector">4-Aug-16</div>
    <div class="selector">4-Aug-16</div>
    <div class="selector">4-Aug-16</div>
    <div class="selector">4-Aug-16</div>
    <div class="selector">4-Aug-16</div>
    <div class="selector">4-Aug-16</div>
    <div class="selector active" id="today">15-Aug-16</div>
    <div class="selector">4-Aug-16</div>
    <div class="selector">4-Aug-16</div>
    <div class="selector">4-Aug-16</div>
    <div class="selector">4-Aug-16</div>
    <div class="selector">4-Aug-16</div>
    <div class="selector">4-Aug-16</div>
    <div class="selector">4-Aug-16</div>
    <div class="selector">4-Aug-16</div>
  </div>
  <div class="bar"></div>
</div>

我想得到它，以便在加载页面时，它会自动将侧边导航栏的 View 置于 today id 元素的中心。我试过放置 myUrl#today 但这改变了整个页面滚动，这是我不想要的。我

我只希望侧导航栏中的滚动条更改其位置并以 #today 位为中心。有谁知道这样做的方法吗？

我也愿意使用 jQuery 和 JS。

谢谢。

Answer 1

我认为你可以使用 jQuery 代码，例如

$(document).ready(function(){
  // when document is ready
  // first check if #today is defined in HTML
  // the $('') is the jQuery selector of to select an element
  // $('#today') means select an element with the ID "today"
  // the .length attribute is default javascript attribute to check 
  //     how many of elements selected has existed
  if($('#today').length > 0){
    // the offset() function is a jQuery function that is used for check the
    //    relative distance from the border of current element to its parent
    var distance_to_top = $('#today').offset().top;
    var top_label_height = $('.label').height();
    var distance_to_scroll = distance_to_top - top_label_height - 8; 
    // 8 px is body margin on jsfiddle
    // scrollTop() function is another jQuery function to scroll an     
    //     overflow element
    $('.filler').scrollTop(distance_to_scroll);
  }
});

找到今天元素相对于其父元素的偏移量，然后减去标签高度，因为标签将覆盖#today 的顶部。滚动到顶部

可以在here 找到演示。