personal-conference/app/views/admin/writing_conferences/index.html.erb

<script src="https://kit.fontawesome.com/1fa49cfdc9.js" crossorigin="anonymous"></script>
<script>
function MergeUrl(){
  location.href = '<%= merge_admin_writing_conferences_path %>'
}
</script>
<table class="table main-list">
  <thead>
    <tr>
      <th class="span1"><%= t('personal_plugins.year') %></th>
      <th class="span7"><%= t('module_name.personal_conference') %></th>
      <th class="span1"><%= t('personal_plugins.author') %></th>
    </tr>
  </thead>
  <tbody id="tbody_writing_conferences" class="sort-holder">
    <%= render 'writing_conference' %>
  </tbody>
</table>

<div class="bottomnav clearfix">
  <div class="action pull-right">
    <div class="dropup upload-button">
      <button class="btn btn-primary" type="button" onclick="MergeUrl()">
        <i class="far fa-object-group"></i>
        <span class="group"></span><%= t('personal_conference.merge') %>
      </button>
      <button class="btn btn-primary dropdown-toggle" type="button" data-toggle="dropdown">
        <i class="icon-upload-alt icon-white"></i><%= t('personal_conference.upload') %>
        <span class="caret"></span>
      </button>
      <div class="dropdown-menu upload-box">
        <form action="/admin/writing_conferences/import_from_excel" method="post" enctype="multipart/form-data">
          <%= hidden_field_tag :authenticity_token, form_authenticity_token %>
          <input type="file" name="import_file" >
            <button class="btn btn-primary" type="submit"><%= t(:submit) %></button>
            <a class="" href="/admin/writing_conferences/download_excel_format.xlsx">Download excel format</a>
        </form>
      </div>
    </div>
    <%= link_to content_tag(:i, nil, :class => 'icon-plus icon-white') + t(:new_), new_admin_writing_conference_path, :class => 'btn btn-primary' %>
  <%= link_to content_tag(:i, nil, :class => 'icon-cog icon-white') + t('setting'), admin_writing_conference_setting_path, :class => 'btn btn-primary pull-right' %>
  </div>
  <div class="pagination pagination-centered">
    <%= content_tag :div, paginate(@writing_conferences), class: "pagination pagination-centered" %>
  </div>
</div>
<% if params[:error] == "1" %>
  <script type="text/javascript">
    alert("File cannot be imported. File has more than 500 entries. Please seperate the entries in different files.");
    window.location.href = "<%= admin_writing_conferences_url %>"
  </script>
<% end %>