Question

我有以下型号：

class Account
  has_many :account_configs
  accepts_nested_attributes_for :account_configs
end

class AccountConfig
  belongs_to :account
end

控制器

def show
end


def new
  @account = Account.new
  @account_config = @account.account_configs.build
end

def create
  @account = Account.new(account_params)
  if @account.save
    redirect_to account_path(@account), notice: 'Account was successfully created.'
  else
    render :new
  end
end

def account_params
      params.require(:account).permit(:name, account_configs_attributes: [:id, :type, :duration, :branch]) if params[:account]
end

以嵌套形式创建模型Account后，我应该在show页面中显示它。我需要遍历此ActiveRecord_Associations_CollectionProxy-@account.account_configs。以前也有一个layout_builder文件。我还需要为此页面扩展相同的布局。当我尝试像这样循环

@account.account_configs.each do |config|
  #here extending from the layout which has other check methods
end

我收到此错误：undefined method each_with_index for #<AccountConfig:0----->。

但如果我在同一页面上使用each，则可以扩展并渲染布局，而不是where。我可以使用where，但是要重复很多代码。在这种情况下，我应该怎么做才能使此错误消失？

错误日志

D, [2019-07-24T14:06:35.851681 #25672] DEBUG -- :   Account Load (1.2ms)  SELECT  `accounts`.* FROM `accounts` WHERE `accounts`.`id` = 5 LIMIT 1
D, [2019-07-24T14:06:35.863820 #25672] DEBUG -- :   AccountConfig Load (1.3ms)  SELECT  `account_config`.* FROM `account_config` WHERE `account_config`.`account_id` = 5  ORDER BY `account_config`.`id` ASC LIMIT 1
D, [2019-07-24T14:06:35.874536 #25672] DEBUG -- :   CACHE (0.0ms)  SELECT  `account_config`.* FROM `account_config` WHERE `account_config`.`account_id` = 5  ORDER BY `account_config`.`id` ASC LIMIT 1  [["account_id", 5]]
D, [2019-07-24T14:06:35.887123 #25672] DEBUG -- :   Account Load (1.1ms)  SELECT `accounts`.`id`, `accounts`.`name` FROM `accounts` WHERE `accounts`.`account_id` = 5
D, [2019-07-24T14:06:35.896571 #25672] DEBUG -- :   AccountConfig Load (1.2ms)  SELECT  `account_config`.* FROM `account_config` WHERE `account_config`.`account_id` = 5  ORDER BY `account_config`.`id` ASC LIMIT 1000
I, [2019-07-24T14:06:35.922217 #25672]  INFO -- :   Rendered customer/accounts/show.html.erb within layouts/customer (62.6ms)
I, [2019-07-24T14:06:35.930145 #25672]  INFO -- : Completed 500 Internal Server Error in 101ms (ActiveRecord: 6.9ms)
F, [2019-07-24T14:06:35.960592 #25672] FATAL -- : 
NoMethodError - undefined method `each_with_index' for #<AccountConfig:0x00005581ed35b6e0>:
  lib/layout_builder.rb:693:in `records'
  app/views/customer/accounts/show.html.erb:37:in `block (4 levels) in _app_views_customer_accounts_show_html_erb___136536495548701304_47008262570920'
  lib/layout_builder.rb:641:in `initialize'
  lib/layout_builder.rb:216:in `record_list'
  app/views/customer/accounts/show.html.erb:33:in `block (3 levels) in _app_views_customer_accounts_show_html_erb___136536495548701304_47008262570920'
  app/views/customer/accounts/show.html.erb:31:in `block (2 levels) in _app_views_customer_accounts_show_html_erb___136536495548701304_47008262570920'
  lib/layout_builder.rb:162:in `block in article'
  lib/layout_builder.rb:281:in `level'
  lib/layout_builder.rb:160:in `article'
  app/views/customer/accounts/show.html.erb:2:in `block in _app_views_customer_accounts_show_html_erb___136536495548701304_47008262570920'
  lib/layout_builder.rb:153:in `page'
  app/views/customer/accounts/show.html.erb:1:in `_app_views_customer_accounts_show_html_erb___136536495548701304_47008262570920'

D, [2019-07-24T14:06:36.118610 #25672] DEBUG -- : 
D, [2019-07-24T14:06:36.118734 #25672] DEBUG -- : 
I, [2019-07-24T14:06:36.118873 #25672]  INFO -- : Started POST "/__better_errors/60b69c8a4bd7e26b/variables" for 127.0.0.1 at 2019-07-24 14:06:36 +0530

show.html.erb

<% configs = @account.account_configs %>    

<% configs.each do |config| %>
<div class="custom-class"><h2><%= "#{config.type}" %></h2></div>

  <% a.record_list configs do |rl| %>
    <% rl.header 'duration' %>
    <% rl.header 'branch' %>
    <% rl.records do |data| %>
      <% if data.type == "#{config.type}" %>
        <% rl.show data.duration %>
        <% rl.show data.branch %>
      <% end %>
    <% end %>
  <% end %>
<% end %>

Answer 1

@account.account_configs.each do |config|将循环以块变量AccountConfig的形式为您提供每个config单个对象，您在其上调用了each_with_index

each_with_index仅支持collection/enumerable对象，而不支持单个对象AccountConfig。

当我在User对象上调用该方法时，我遇到了相同的错误

NoMethodError: undefined method `each_with_index' for #<User:0x00000007128c00>

检查关注each_with_index，

lib/layout_builder.rb:216:in `record_list'
lib/layout_builder.rb:693:in `records'

解决方案-

您可以通过将对象config传递为[config]来解决，该对象将充当可枚举的对象

Answer 2

我们不能在单个对象上使用each_with_index，它可以用于活动记录收集。如果您需要当前循环内的account_configs对象的索引。试试这个循环。

@account.account_configs.each_with_index do |config, index|
  # index - will give the current loop count.
end

Rails 4中模型的未定义方法`each_with_index'

2 个答案: