grouped_collection_select 的过滤下拉列表选项答案

【问题标题】：Filter drop down list option for grouped_collection_selectgrouped_collection_select 的过滤下拉列表选项
【发布时间】：2016-08-15 16:37:33
【问题描述】：

这不是作业。我这样做是为了提高我的 RoR 技能。

我同时拥有Manufacturer 和Model 实体。我正确设置了所有关系，用户必须在选择Model 之前选择Manufacturer。我为自己创建的应用程序添加了更多功能。现在，我想从Model 下拉列表中过滤掉name，其中name 包含单词(Other)。

Model 实体中的name 属性示例：F20、F10 (Other)、E90。

我想过滤掉包含(Other) 的模型名称。 SQL 语句为Model.where.not("name LIKE ?", "%(Other)%")。选择manufacturer 后，将显示F20 和E90。 F10 (Other) 将被排除，因为名称中包含单词 (Other)。

这就是我的下拉列表表单。

<%= bootstrap_form_tag url: '/quotation/tints/generate' do |f| %>
    <div class="field">
        <%= f.collection_select :manufacturer_id, Manufacturer.order(:name), :id, :name, {:prompt => "Select Manufacturer"} %> 
    </div>

    <div class="field">
        <%= f.grouped_collection_select :model_id, Manufacturer.order(:name), :models, :name, :id, :name, {:prompt => "Select Model"} %> 
    </div>

    //Some code here that are not related
<% end %>

我尝试过的：在我的tints_controller 中，这个和我已经更新了我的表单，以便使用我修改过的内容。

  def quotation
    @listmanufacturer = Manufacturer.order(:name)
    @listmodel = Model.where.not("name LIKE ?", "%(Other)%")
    render 'quotation'
  end

我的表格

<%= bootstrap_form_tag url: '/quotation/tints/generate' do |f| %>
    <div class="field">
        <%= f.collection_select :manufacturer_id, @listmanufacturer, :id, :name, {:prompt => "Select Manufacturer"} %> 
    </div>

    <div class="field">
        <%= f.grouped_collection_select :model_id, @listmanufacturer, @listmodel, :name, :id, :name, {:prompt => "Select Model"} %> 
    </div>

    //Some code here that are not related
<% end %>

但是，我收到了类似TypeError: nil is not a symbol 的错误消息。我无法修改我的models_controller，因为下拉列表在不同的视图中被使用了几次。有些视图需要带有单词(Other) 的模型，有些则不需要。

@listmodel 是破坏一切的部分。通过将:models 替换为@listmodel，我希望过滤掉包含(Other) 的模型名称。

非常感谢任何帮助！

注意：到目前为止，我的应用程序运行正常。 model 中的所有关系均已正确设置，routes 已配置。

更新，更多日志

ActionView::Template::Error (#<ActiveRecord::Relation [#<Model id: 1, name: "Kancil Old", manufacturer_id: 1, created_at: "2016-08-14 16:12:24", updated_at: "2016-08-14 16:12:24">, #<Model id: 2, name: "Kancil 04", manufacturer_id: 1, created_at: "2016-08-14 16:12:24", updated_at: "2016-08-14 16:12:24">, #<Model id: 3, name: "Kembara", manufacturer_id: 1, created_at: "2016-08-14 16:12:24", updated_at: "2016-08-14 16:12:24">, #<Model id: 4, name: "Kenari", manufacturer_id: 1, created_at: "2016-08-14 16:12:24", updated_at: "2016-08-14 16:12:24">, #<Model id: 5, name: "Kelisa", manufacturer_id: 1, created_at: "2016-08-14 16:12:24", updated_at: "2016-08-14 16:12:24">, #<Model id: 6, name: "Myvi 05", manufacturer_id: 1, created_at: "2016-08-14 16:12:24", updated_at: "2016-08-14 16:12:24">, #<Model id: 7, name: "Rusa", manufacturer_id: 1, created_at: "2016-08-14 16:12:24", updated_at: "2016-08-14 16:12:24">, #<Model id: 8, name: "Viva", manufacturer_id: 1, created_at: "2016-08-14 16:12:24", updated_at: "2016-08-14 16:12:24">, #<Model id: 9, name: "Alza", manufacturer_id: 1, created_at: "2016-08-14 16:12:24", updated_at: "2016-08-14 16:12:24">, #<Model id: 10, name: "Myvi Ii", manufacturer_id: 1, created_at: "2016-08-14 16:12:24", updated_at: "2016-08-14 16:12:24">, ...]> is not a symbol nor a string):
     6:         </div>
     7: 
     8:         <div class="field">
     9:             <%= f.grouped_collection_select :model_id, @listmanufacturer, @listmodel, :name, :id, :name, {:prompt => "Select Model"} %> 
    10:         </div>
    11: 
    12:         <div class="field">

app/views/tints/quotation.html.erb:9:in `block in _app_views_tints_quotation_html_erb__1724914643_132263140'
app/views/tints/quotation.html.erb:3:in `_app_views_tints_quotation_html_erb__1724914643_132263140'
app/controllers/tints_controller.rb:47:in `quotation'
  Rendering C:/Ruby22-x64/lib/ruby/gems/2.2.0/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/rescues/template_error.html.erb within rescues/layout
  Rendering C:/Ruby22-x64/lib/ruby/gems/2.2.0/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/rescues/_source.html.erb
  Rendered C:/Ruby22-x64/lib/ruby/gems/2.2.0/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/rescues/_source.html.erb (9.0ms)
  Rendering C:/Ruby22-x64/lib/ruby/gems/2.2.0/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/rescues/_trace.html.erb
  Rendered C:/Ruby22-x64/lib/ruby/gems/2.2.0/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/rescues/_trace.html.erb (5.0ms)
  Rendering C:/Ruby22-x64/lib/ruby/gems/2.2.0/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/rescues/_request_and_response.html.erb
  Rendered C:/Ruby22-x64/lib/ruby/gems/2.2.0/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/rescues/_request_and_response.html.erb (1.0ms)
  Rendered C:/Ruby22-x64/lib/ruby/gems/2.2.0/gems/actionpack-5.0.0/lib/action_dispatch/middleware/templates/rescues/template_error.html.erb within rescues/layout (539.0ms)
DEPRECATION WARNING: #original_exception is deprecated. Use #cause instead. (called from status_code_with_paginate at C:/Ruby22-x64/lib/ruby/gems/2.2.0/gems/will_paginate-3.1.0/lib/will_paginate/railtie.rb:49)

【问题讨论】：

您在哪一行得到错误？请发布错误的堆栈跟踪
我的猜测：括号可能是需要转义的特殊字符???
@TarynEast 我不这么认为。我在index.html.erb 中使用Model.where.not("name LIKE ?", "%(Other)%")，并且在没有转义字符的情况下工作得很好。
@p4sh4 添加了错误代码，我不确定这是否是您的意思。
在您的服务器日志中（例如log/development.log），您将能够找到应用程序中发生的所有事情的列表...包括您遇到的错误（type error）和紧随其后的是一大组 20-30 行，看起来像带数字的文件名。该集合称为堆栈跟踪，它准确地向您显示导致错误的代码行。看看其中的前 3-4 行对我们（以及您的扩展）会有所帮助:)

标签： sql ruby-on-rails ruby

【解决方案1】：

在我的Manufacturer model，

class Manufacturer < ApplicationRecord
    //Something here
    def listmodel 
        models.where.not("name LIKE ?", "%(Other)%")
    end 
end

在我的form，

<%= bootstrap_form_tag url: '/quotation/tints/generate' do |f| %>
        <div class="field">
            <%= f.collection_select :manufacturer_id, Manufacturer.all.order(:name), :id, :name, {:prompt => "Select Manufacturer"} %> 
        </div>

        <div class="field">
            <%= f.grouped_collection_select :model_id, Manufacturer.all.order(:name), :listmodel, :name, :id, :name, {:prompt => "Select Model"} %> 
        </div>
        //More code here
<% end %>

现在在我的下拉列表中，名称包含 (Other) 的模型将被排除在外。

【讨论】：