我有一个Bootstrap 4崩溃如下......
<a data-toggle="collapse" href="#collapseNEWS" aria-expanded="true" aria-controls="collapseNEWS"><i class="fa fa-chevron-circle-up" aria-hidden="true"></i></a>
<div class="row collapse in" id="collapseNEWS">Content</div>
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除非单击字体真棒图标,否则会自动显示内容.我在初始加载时显示fa-chevron-circle-up图标.
单击图标后,内容将关闭,我想显示fa-chevron-circle-down图标.我怎么做到这一点?
我查看了alpha文档:http: //v4-alpha.getbootstrap.com/components/collapse/
......但我不清楚我如何建立状态以显示......
<i class="indicator fa fa-chevron-circle-up" aria-hidden="true"></i>
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要么...
<i class="indicator fa fa-chevron-circle-down" aria-hidden="true"></i>
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谢谢新泽西州