jQuery 实现 modal 可以拖放
Gemfile
gem 'jquery-ui-rails'
执行 bundle install ，重启 rails s
application.js
//= require jquery-ui/widgets/draggable
application.scss
*= require jquery-ui/draggable
// application.js
$(document).ready(function() {
$("#complainModal").find(".modal-dialog").draggable({
handle: ".modal-header"
});
}）
html.erb
<div class="modal fade modal-draggable message-modal-style" id="complainModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel">
<div class="modal-dialog ui-draggable">
<div class="modal-content">
<div class="modal-header ui-draggable-handle">
<button type="button" class="close" data-dismiss="modal" aria-label="Close">
<span aria-hidden="true">×</span>
</button>
<h4 class="modal-title" id="complainModalLabel">您对本题有什么想说的？</h4>
</div>
<%= render "form" %>
</div>
</div>
</div>