嵌套表格不及格belongs_to的：ID

Question

我有以下型号

class Project < ActiveRecord::Base 
    has_many :assignments, :conditions => {:deleted_at => nil} 
    has_many :members, :conditions => {:deleted_at => nil} 
    accepts_nested_attributes_for :members, :allow_destroy => true 
end 

class Member < ActiveRecord::Base 
    belongs_to :project 
    belongs_to :person 
    belongs_to :role 

    has_many :assignments, :dependent => :destroy, :conditions => {:deleted_at => nil} 
    accepts_nested_attributes_for :assignments, :allow_destroy => true 


    validates_presence_of  :role_id 
    validates_presence_of  :project_id 
end 

，我以为控制器将填充在project.save的member.project_id每个嵌套成员记录。但是，我收到验证错误，指出project_id为空。

我控制器的方法：

def create 
    # @project is created in before_filter 
    if @project.save 
     flash[:notice] = "Successfully created project." 
     redirect_to @project 
    else 
     render :action => 'new' 
    end 
    end 

我是否需要手动设置PROJECT_ID在每个嵌套成员记录？或者当创建成员记录时，控制器需要填充什么？

Answer 1

创建Member对象是这样的：

@member = @project.members.build