如何使用带有下拉列表的引导程序

Question

下拉表单显示在页面上，但类别只是笨拙地漂浮在它下面，单击下拉表单没有任何作用。如果我从下拉表单中取出引导程序，那么它就可以完美地工作，但它是一个丑陋的默认版本。

_form.html.erb

<form>
    <select class="form-control">
    <%= f.collection_select :categories, Value::VALUES, :to_s, :to_s, :include_blank => true, class: 'form-control', placeholder: 'Choose Category' %>
  </select>
</form>

价值.rb 模型

class Value < ActiveRecord::Base
    belongs_to :user
    VALUES = ['Courage', 'Determination', 'Gratitude', 'Humor']
end

整个形式

<%= form_for(@value) do |f| %>
  <% if @value.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(@value.errors.count, "error") %> prohibited this value from being saved:</h2>
      <ul>
      <% @value.errors.full_messages.each do |message| %>
        <li><%= message %></li>
      <% end %>
      </ul>
    </div>
  <% end %>
<div class="america">
<form>
  <div class="form-group">
    <%= f.text_field :name, class: 'form-control', placeholder: 'Enter Value' %>
  </div>
  <select class="form-control">
    <%= f.collection_select :categories, Value::VALUES, :to_s, :to_s, :include_blank => true, class: 'form-control', placeholder: 'Choose Category' %>
  </select>
  <%= button_tag(type: 'submit', class: "btn") do %>
  <span class="glyphicon glyphicon-plus"></span>
  <% end %>
  <%= link_to values_path, class: 'btn' do %>
  <span class="glyphicon glyphicon-chevron-left"></span>
  <% end %>
  <%= link_to @value, method: :delete, data: { confirm: 'Are you sure?' }, class: 'btn' do %>
  <span class="glyphicon glyphicon-trash"></span>
  <% end %>
  </form>
</div>
<% end %>

Answer 1

谢谢 ptd

<%= f.collection_select :categories, Value::VALUES, :to_s, :to_s, { :include_blank => true }, {class: 'form-control', placeholder: 'Choose Category'} %>