具有默认/设置值的多个嵌套表单

Question

我必须在 Rails 中重建一个如下所示的表单：

您正在查看的是一个可以有多个年级（或学年）的学生，并且对于每个年级（或学年），您都可以添加评估。共有三个评估（开始、中期和最终），每个评估都有一定数量的科目。我得到了他们所在学校的可用科目，以便价值可以更新/改变，但我只希望有学校教授的科目。用户不应该能够“添加主题”...我想像您在上面看到的那样定义它们。

我的问题是，我该如何实现？我有它的工作，所以我可以为学生添加无限数量的成绩（或学年），但我无法弄清楚如何无缝添加另一个嵌套表格，按每个年级的评估分类，所有科目都预设在每个年级下评估。型号如下：

Class Student < ApplicationRecord

  belongs_to :school
  has_many :student_grades, inverse_of: :student, dependent: :destroy
  accepts_nested_attributes_for :student_grades, reject_if: :all_blank, allow_destroy: true

  validates :status, presence: true
  validates :school_id, presence: true
  validates :first_name, presence: true
  validates :middle_name, presence: false
  validates :last_name, presence: true

  enum :status => [:active, :applying, :graduated, :expelled]

end

class StudentGrade < ApplicationRecord

  belongs_to :student
  belongs_to :computer, optional: true
  has_many :student_grade_subject_assessments, inverse_of: :student_grade, dependent: :destroy
  accepts_nested_attributes_for :student_grade_subject_assessments, reject_if: :all_blank, allow_destroy: true

  validates :student_id, presence: true
  validates :school_year, presence: true
  validates :grade, presence: true
  validates :computer_id, presence: false

end

class StudentGradeSubjectAssessment < ApplicationRecord

  belongs_to :student_grade
  belongs_to :subject

  validates :student_grade_id, presence: true
  validates :subject_id, presence: true
  validates :assessment_type, presence: true
  validates :percentage, presence: false
  validates :comments, presence: false
  validates :plan, presence: false

  enum :assessment_type => [:beginning_assessment, :mid_term_assessment, :final_assessment]

end

_form.html.erb

<%= form_for(@student, html: { multipart: true }) do |f| %>

    <div class="tab-content">
      <div class="tab-pane active" id="student-profile">
        <div class="row">
          <div class="col-xs-12 col-sm-4">
            <div class="form-group">
              <%= f.label :last_name, 'Last Name' %><br>
              <%= f.text_field :last_name, class: 'form-control' %>
            </div>
          </div>
          <div class="col-xs-12 col-sm-4">
            <div class="form-group">
              <%= f.label :first_name, 'First Name' %><br>
              <%= f.text_field :first_name, class: 'form-control' %>
            </div>
          </div>
          <div class="col-xs-12 col-sm-4">
            <div class="form-group">
              <%= f.label :middle_name, 'Middle Name' %><br>
              <%= f.text_field :middle_name, class: 'form-control' %>
            </div>
          </div>
          <div class="col-xs-12 col-sm-4">
            <div class="form-group">
              <%= f.label :school_id %><br>
              <%= f.collection_select :school_id, School.all.order(:name), :id, :name, {prompt: "Choose..."}, {class: 'form-control'} %>
            </div>
          </div>
        </div>
      </div>
      <div class="tab-pane" id="grades">
        <%= f.fields_for :student_grades do |student_grade| %>
            <%= render 'student_grade_fields', :f => student_grade %>
        <% end %>
        <div class='links'>
          <%= link_to_add_association 'Add School Year', f, :student_grades, class: "btn btn-success" %>
        </div>
      </div>
    </div>

    <%= f.submit "Save Student", class: "btn btn-success" %>

<% end %>

_student_grade_fields.html.erb 只包含相应模型的字段，但这也是我为StudentGradeSubjectAssessment 放置表单的地方。

Answer 1

您似乎想要这样的东西：

@student.student_grades.each do |grade|
  ...year, grade, computer stuff for the grade

  grade.student_grade_subject_assessments.where(assessment_type: :beginning_assessment).each do |assessment|
    ...stuff for each beginning assessment per subject
  end

  grade.student_grade_subject_assessments.where(assessment_type: :middle_assessment).each do |assessment|
    ...stuff for each middle assessment per subject
  end

  grade.student_grade_subject_assessments.where(assessment_type: :end_assessment).each do |assessment|
    ...stuff for each final assessment per subject
  end
end

您还可以通过按评估类型对一个查询进行分组来为每种评估类型保存多个查询，如下所示：

grade.student_grade_subject_assessments.group_by(:assessment_type)

这将生成一个哈希，其中键是评估类型，值是该评估类型的所有科目的数组（已按年级划分）。这是doc 的示例。