javascript - 如何在Bootstrap中为*独立*几个进度条部分设置动画？

Question

我有一些 Bootstrap 代码，当用户查看它时，它可以很好地为进度条部分设置动画。

然而它动画 全部 页面中的进度条而不是动画仅限 该查看部分中的进度条。结果，当用户转到进度条的另一部分时，这些已经是动画的，他看不到任何动画。

那么我的问题是:如何修改下面的代码以在查看不同部分时独立制作动画？

CSS

#skills {
  padding: 60px 0;
}

#skills .progress {
  height: 35px;
  margin-bottom: 10px;
}

#skills .progress .skill {
  font-family: "Open Sans", sans-serif;
  line-height: 35px;
  padding: 0;
  margin: 0 0 0 20px;
  text-transform: uppercase;
}

#skills .progress .skill .val {
  float: right;
  font-style: normal;
  margin: 0 20px 0 0;
}

#skills .progress-bar {
  width: 1px;
  text-align: left;
  transition: .9s;
}

JS

// Skills section
$('#skills').waypoint(function() {
  $('.progress .progress-bar').each(function() {
    $(this).css("width", $(this).attr("aria-valuenow") + '%');
  });
}, { offset: '80%'} );

HTML

<!-- The first section of progress bars somewhere in the page -->
<section id="skills">
  <div class="skills-content">
    <div class="progress">
      <div class="progress-bar" role="progressbar" aria-valuenow="60" aria-valuemin="0" aria- 
   valuemax="100"></div>
        <span class="skill">Skillset 1 - Skill 1 <i class="val"></i></span>
      </div>
    </div>
    <div class="progress">
      <div class="progress-bar" role="progressbar" aria-valuenow="20" aria-valuemin="0" aria- 
   valuemax="100"></div>
        <span class="skill">Skillset 1 - Skill 2 <i class="val"></i></span>
    </div>
  </div>
</section>

<!-- Another section of progress bars further down the page -->
<section id="skills">
  <div class="skills-content">
    <div class="progress">
      <div class="progress-bar" role="progressbar" aria-valuenow="40" aria-valuemin="0" aria- 
   valuemax="100"></div>
        <span class="skill">Skillset N - Skill 1 <i class="val"></i></span>
      </div>
    </div>
    <div class="progress">
      <div class="progress-bar" role="progressbar" aria-valuenow="80" aria-valuemin="0" aria- 
   valuemax="100"></div>
        <span class="skill">Skillset N - Skill 2 <i class="val"></i></span>
      </div>
    </div>
    <div class="progress">
      <div class="progress-bar" role="progressbar" aria-valuenow="20" aria-valuemin="0" aria- 
   valuemax="100"></div>
        <span class="skill">Skillset N - Skill 3 <i class="val"></i></span>
    </div>
  </div>
</section>

Answer 1

我只是注意到你没有正确关闭你的部分元素和其他标签

<section class="skills">
    <div class="skills-content">
        <div class="progress">
            <div class="progress-bar" role="progressbar" aria-valuenow="60" aria-valuemin="0" aria- valuemax="100">
            </div>
            <span class="skill">Skillset 1 - Skill 1 <i class="val"></i></span>
        </div>
        <div class="progress">
            <div class="progress-bar" role="progressbar" aria-valuenow="20" aria-valuemin="0" aria- valuemax="100">
            </div>
            <span class="skill">Skillset 1 - Skill 2 <i class="val"></i></span>
        </div>
    </div>
</section>

<!-- Another section of progress bars further down the page -->
<section class="skills">
    <div class="skills-content">
        <div class="progress">
            <div class="progress-bar" role="progressbar" aria-valuenow="40" aria-valuemin="0" aria- valuemax="100">
            </div>
            <span class="skill">Skillset N - Skill 1 <i class="val"></i></span>
        </div>
        <div class="progress">
            <div class="progress-bar" role="progressbar" aria-valuenow="80" aria-valuemin="0" aria- valuemax="100">
            </div>
            <span class="skill">Skillset N - Skill 2 <i class="val"></i></span>
        </div>
        <div class="progress">
            <div class="progress-bar" role="progressbar" aria-valuenow="20" aria-valuemin="0" aria- valuemax="100">
            </div>
            <span class="skill">Skillset N - Skill 3 <i class="val"></i></span>
        </div>
    </div>
</section>

当你的航点功能调用你所有的进度元素而不是只有子进度元素时

$('#skills').waypoint(function() {
  $('.progress .progress-bar').each(function() { // <- you are getting all progress elements
    $(this).css("width", $(this).attr("aria-valuenow") + '%');
  });
}, { offset: '80%'} );

改成

$('.skills').waypoint(function () {
   var el = this.element;
   var children = $(el).find(".progress-bar");
   $(children).each(function () { // <- make sure getting only children elements
        $(this).css("width", $(this).attr("aria-valuenow") + '%');
   });
}, { offset: '80%' });

并确保其他技能部分在页面加载时不被用户查看(不在视口(viewport)中)