Rails 3.2.1嵌套表单和accepts_nested_attributes_for返回:: Client（xxxxx）expected，got array（xxxxx）“

Question

请在我输入所有数据后，当我尝试保存我的数据输入表格（复杂表格）时，请帮助我了解我出错的地方以便收到此消息？

我有五个模型如下：

class Contract < AR::Base
  has_many :clientlines
  has_many :codelines
  has_many :clients, :through => :clientlines
  has_many :codes, :through => :codelines

  accepts_nested_attributes_for :clientlines
end

class Clientline < AR::Base
  belongs_to :contract
  belongs_to :client

  accepts_nested_attributes_for :contract
end

class Client < AR::Base
  has_many :clientlines
  has_many :contracts, :through => :clientlines
end

class Codeline < AR::Base
  belongs_to :contract
  belongs_to :code
  units_alloc

  accepts_nested_attributes_for :code
end

class Code < AR::Base
  has_many :codelines
  has_many :contracts, :through => :codelines
end

我使用以下文章作为我的设计来源：

http://rubysource.com/complex-rails-forms-with-nested-attributes/

在我的app / controller / contracts_controller.rb中，我有以下内容：

def new
  @contract = Contract.new
  4.times { @contract.codes.build }
  4.times { @contract.codelines.build }
end

def create
  @contract = Contract.new(params[:contract])
  if @contract.save
    flash[:success] = "New Contract has been saved"
    redirect_to @contract # this redirects to the contract show page
  else
    @title = "You have some errors"
    render 'new'
  end
end
.
.
.
end

我将复杂的表格放在一起如下：

- provide(:title, 'Add Contract')
%h2 New Contract
=form_for(@contract) do |f|
  =render 'shared/contract_error_messages', object: f.object
  =render 'fields', f:  f
  .actions
    = f.submit "Save", class: 'save strong round'

部分_fields：

<fieldset><legend>Enter Contract Details</legend>
.field
  = f.label :name, "AuthNum"
  %br/
  = f.text_field  :authnum, :size => 10, :class => "ui-state-default"
.field
  = f.label :name, "Start Date"
  %br/
  = f.text_field  :st_date, :size => 12, :class => "ui-state-default"
.field
  = f.label :name, "End Date"
  %br/
  = f.text_field  :end_date, :size => 12, :class => "ui-state-default"
</fieldset>
<fieldset><legend>Enter Client Details</legend>
= f.fields_for :clients do |ff|
  .field
    = ff.label :name, "First Name"
    %br/
    = ff.text_field :f_name, :size => 15, :class => "ui-state-default"
  .field
    = ff.label :name, "MI"
    %br/
    = ff.text_field :mi, :size => 3, :class => "ui-state-default"
  .field
     = ff.label :name, "Last Name"
     %br/
     = ff.text_field :l_name, :size => 15, :class => "ui-state-default"
  .field
     = ff.label :name, "Birth Date"
     %br/
     = ff.text_field :birth_date, :size => 12, :class => "ui-state-default"
  .field
     = ff.label :name, "Address1"
     %br/
     = ff.text_field :address1, :size => 25, :class => "ui-state-default"
  .field
     = ff.label :name, "Address2"
     %br/
     = ff.text_field :address2, :size => 25, :class => "ui-state-default"
  .field
     = ff.label :name, "City"
     %br/
     = ff.text_field :city, :size => 15, :class => "ui-state-default"
  .field
     = ff.label :name, "ZipCode"
     %br/
     = ff.text_field :zip_code, :size => 10, :class => "ui-state-default"
  .field
     = ff.label :name, "State"
     %br/
     = ff.text_field :state, :size => 15, :class => "ui-state-default"
  .field
     = ff.label :name, "MedicareNum"
     %br/
     = ff.text_field :medicarenum, :size => 20, :class => "ui-state-default"
  .field
     = ff.label :name, "MedicaidNum"
     %br/
     = ff.text_field :medicaidnum, :size => 20, :class => "ui-state-default"
  .field
     = ff.label :name, "MemberNum"
     %br/
     = ff.text_field :membernum, :size => 20, :class => "ui-state-default"
  .field
     = ff.label :name, "SocSerCareMgr"
     %br/
     = ff.text_field :socsercaremgr, :size => 20, :class => "ui-state-default"
  .field
     = ff.label :name, "SSCM_Ph"
     %br/
     = ff.text_field :sscm_ph, :size => 15, :class => "ui-state-default"
  .field
     = ff.label :name, "NurseCareMgr"
     %br/
     = ff.text_field :nursecaremgr, :size => 20, :class => "ui-state-default"
  .field
     = ff.label :name, "NCM_Ph"
     %br/
     = ff.text_field :ncm_ph, :size => 15, :class => "ui-state-default"
  .field
     = ff.label :name, "EmergencyContact"
     %br/
     = ff.text_field :emergencycontact, :size => 20, :class => "ui-state-default"
  .field
     = ff.label :name, "EC_Ph"
     %br/
     = ff.text_field :ec_ph, :size => 15, :class => "ui-state-default"
  .field
     = ff.label :name, "PrimaryCarePhy"
     %br/
     = ff.text_field :primarycarephy, :size => 20, :class => "ui-state-default"
  .field
     = ff.label :name, "PCPhy_Ph"
     %br/
     = ff.text_field :pcphy_ph, :size => 15, :class => "ui-state-default"
</fieldset>
<fieldset><legend>Enter Billing Code Details</legend>
= f.fields_for :codes do |ff|
  .field
    = ff.label :name, "Code Name"
    %br/
    = ff.text_field :code_name, :size => 15, :class => "ui-state-default"
  .field
    = ff.label :name, "Status"
    %br/
    = ff.text_field :status, :size => 10, :class => "ui-state-default"
  .field
    = ff.label :name, "Description"
    %br/
    = ff.text_field :description, :size => 25, :class => "ui-state-default"
= f.fields_for :codelines do |ff|
  .field
    = ff.label :name, "Units Alloc"
    %br/
    = ff.text_field :units_alloc, :precision => 6, :scale => 2, :size => 10, :class => 
    "ui-state-default"
</fieldset>

我的首要问题是，一旦我输入了表单上的所有数据，然后按下“保存”即可。按钮我得到以下内容：

CollactsController中的ActiveRecord :: Association TypeMisMatch #Create。 预期客户端（#xxxxxx），得到阵列（#xxxxxx）。

另一个问题是，如果我包含＆＃39; accepts_nested_attributes_for：codelines＆＃39;在我的合约模型中，＆＃39; units_alloc＆＃39;属性从我的表单中消失。

在这两个问题上，我们将非常感谢任何帮助或指导。我花了一些时间阅读复杂的表格，观看了复杂的表格和＃39;我已阅读并重新阅读关于关联的Rails指南以及accept_nested_attributes_for方法的API文档。显然，我对这些概念的理解还没有达到解决这些问题所需的全面理解，因此我呼吁帮助。

更新 应用程序/控制器/ contracts_controller.rb

class ContractsController < ApplicationController

def index
  @contracts = Contract.paginate(page: params[:page])
end

def show
  @contract = Contract.find(params[:id])
end

def new
  @contract = Contract.new
  @contract.codes.build
  @contract.codelines.build
  @contract.clients.build
end

def create
  raise params[:contract].to_s ------ **this is line #19**
  @contract = Contract.new(params[:contract])
  if @contract.save
    flash[:success] = "New Contract has been saved"
    redirect_to @contract # this redirects to the contract show page
  else
    @title = "You have some errors"
    render 'new'
  end
end

def edit
  @contract = Contract.find(param[:id])
end

def update
  if @contract.update_attributes(params[:contract])
    flash[:success] = "Contract Profile updated"
    redirect_to @contract
  else
    render 'edit'
  end
end
end

我添加了＆＃34;提升参数[：contract] .to_s＆＃34;作为我在contract_controller.rb中创建操作的第一行，输出如下：

RuntimeError in ContractsController#create

{"authnum"=>"700900", "st_date"=>"04/03/2012", "end_date"=>"06/29/2012", "clients"=> 
{"f_name"=>"Lefty", "mi"=>"L", "l_name"=>"Right", "birth_date"=>"07/18/1979", 
"address1"=>"54 Frosty Lane", "address2"=>"", "city"=>"Frave", "zip_code"=>"54806",
"state"=>"WI", "medicarenum"=>"789987456", "medicaidnum"=>"931579135", 
"membernum"=>"890333-3", "socsercaremgr"=>"Caring Serving",
"sscm_ph"=>"1-444-444-4444", "nursecaremgr"=>"Caring Nurse", 
"ncm_ph"=>"1-555-555-5555", "emergencycontact"=>"Quick Response", 
"ec_ph"=>"1-666-666-6666", "primarycarephy"=>"This One", "pcphy_ph"=>"1-777-777-7777"},
"codes"=>{"code_name"=>"S-5463", "status"=>"Active", "description"=>"Transition from
sch to mkt"}, "codelines"=>{"units_alloc"=>"80.00"}}

Rails.root: /home/tom/rails_projects/tracking
Application Trace | Framework Trace | Full Trace

app/controllers/contracts_controller.rb:19:in `create'

Request

Parameters:

{"utf8"=>"✓",
"authenticity_token"=>"/i21h2vwzuDPjIrCXzYEIAg41FnMxfGdCQQggjqcZjY=",
"contract"=>{"authnum"=>"700900",
"st_date"=>"04/03/2012",
"end_date"=>"06/29/2012",
"clients"=>{"f_name"=>"Lefty",
"mi"=>"L",
"l_name"=>"Right",
"birth_date"=>"07/18/1979",
"address1"=>"54 Frosty Lane",
"address2"=>"",
"city"=>"Frave",
"zip_code"=>"54806",
"state"=>"WI",
"medicarenum"=>"789987456",
"medicaidnum"=>"931579135",
"membernum"=>"890333-3",
"socsercaremgr"=>"Caring Serving",
"sscm_ph"=>"1-444-444-4444",
"nursecaremgr"=>"Caring Nurse",
"ncm_ph"=>"1-555-555-5555",
"emergencycontact"=>"Quick Response",
"ec_ph"=>"1-666-666-6666",
"primarycarephy"=>"This One",
"pcphy_ph"=>"1-777-777-7777"},
"codes"=>{"code_name"=>"S-5463",
"status"=>"Active",
"description"=>"Transition from sch to mkt"},
"codelines"=>{"units_alloc"=>"80.00"}},
"commit"=>"Save"}

更新1

我将contract_controller的新动作更改为：

def new
  @contract = Contract.new

通过契约构建代码行对象，然后通过代码行对象构建代码

  codelines = @contract.codelines.build
  codelines.codes.build

通过合同构建clientlines对象，然后通过clientlines对象构建客户端

  clientlines = @contract.clientlines.build
  clientlines.clients.build
end

我还通过添加accepts_nested_attributes_for：clientlines，：codelines以及添加attr_accessor行来更改我的合约模型。

class Contract < ActiveRecord::Base
  has_many :clientlines
  has_many :codelines
  has_many :clients, :through => :clientlines
  has_many :codes, :through => :codelines

  accepts_nested_attributes_for :clients
  accepts_nested_attributes_for :codes
  accepts_nested_attributes_for :clientlines
  accepts_nested_attributes_for :codelines

  attr_accessor :codes, :clients, :clientlines, :codelines
end

我现在在我的参数中有关联名称的nested_attribute_writers，但现在我的错误已更改为：

NoMethodError in ContractsController#new

undefined method `build' for nil:NilClass

现在的问题是，＆＃34;让attr_accessor引用所有关联是否正确？＆＃34; 我的另一个问题是，＆＃34;我是否必须使用form_helper为客户端，代码和代码行创建记录？＆＃34;我问这个的原因是，尽管我在contract_controller中有构建操作，但似乎它仍然是零。 如果对第二个问题的回答是肯定的，你可以指导我一些资源来指导我建立一个form_helper吗？我正在检查RailsGuides。

感谢。

更新2

我一直在圈子里，我将contract_controller的新动作改为：

def new
  @contract = Contract.new

  @contract.codes.build
  @contract.clients.build
end

我还将合同模型改回：

class Contract < ActiveRecord::Base
  has_many :clientlines
  has_many :codelines
  has_many :clients, :through => :clientlines
  has_many :codes, :through => :codelines

  accepts_nested_attributes_for :clients
  accepts_nested_attributes_for :codes

  attr_accessible :clients_attributes, :codes_attributes etc
end

最后，我删除了我的视图partial，_ fields.html.haml中与代码行相关的部分，即：

= f.fields_for :codelines do |ff| and the next four lines

现在我的params有必要的＆＃34; clients_attributes＆＃34;和＆＃34; codes_attributes＆＃34;结果表格保存到适当的表格中。我还有一些问题，即代码行中的额外属性，＆＃39; units_alloc＆＃39;和其他一些事情，但事情看起来更好。

Answer 1

好的，所以问题在于表单的设置方式。

您的contract模型可以接受clientlines的嵌套属性，但是，您尝试接受clients，code的嵌套属性。

为此，您需要按照以下方式设置Contract模型：

class Contract < AR::Base
  has_many :clientlines
  has_many :codelines
  has_many :clients, :through => :clientlines
  has_many :codes, :through => :codelines

  accepts_nested_attributes_for :codes
  accepts_nested_attributes_for :clients
end

我想我理解你的困惑，因为ClientLines是codes和clients的所有者，你应该接受嵌套属性的关系，但这是不正确的。

使用has_many :codes, :through => :clientlines后，您已在Contract和Code之间设置了第一类关联，因此，如果您想在codes中创建新的contract }表单，然后您需要在accepts_nested_attributes_for :codes模型中说Contract。

希望这有帮助。

因此，关于您上次发布参数的问题，问题是:codes和:clients。如果您的accepts_nested_attributes_for :codes模型中有accepts_nested_attributes_for :clients和Contract代码，那么这应该可以正常使用。

问题是，为了正确构建客户端或代码，您还需要构建其父对象。所以你的控制器看起来应该更像这样：

class ContractsController < ApplicationController
  def new
    @contract = Contract.new

    #Build the codelines object throught the contract, then build the codes through the codelines object
    codelines =  @contract.codelines.build
    codelines.build_code

    # Do the same for the clients
    clientlines = @contract.clientlines.build
    clientlines.build_client
  end

现在，如果您已正确完成此操作，而不是在:clients中看到:codes或params，则应该看到:clients_attributes或:codes_attributes。< / p>

我真的认为应该这样做。

Answer 2

第一个答案是一个很大的帮助，但它没有让我一直到解决方案。 我找到了一个解决方案，它确实将我带到了这个网站的最后debugging nested_forms。

这是你读过的第九个项目，如果你正在使用has_many：通过关联，那么你需要将你的nested_form基于连接模型或接近它的东西。

我通过在这里和那里重构一些代码来快速运行测试，现在我有一个可行的嵌套表单，它向控制器提供正确的参数，然后控制器正确地处理它，我的代码行表现在只有一个记录。