ruby-on-rails - 带有 Rails 5.1 form_with 的嵌套资源

Question

每 this pull request我可以看到一个数组应该传递给 form_with的模型参数。但是，当我提供以下内容时:

<%= form_with(model: [@trip, @activity], local: true) do |f| %>
  ...
<% end %>

Rails 将返回 - ActionView::Template::Error (undefined method activity_path' for #<#<Class:0x007f80231e3070>:0x007f8023010dd8>):
我的路线文件看起来像:

  resources :trips do
    resources :activities
  end

rake routes的输出好像 -

     trip_activities GET    /trips/:trip_id/activities(.:format)          activities#index
                     POST   /trips/:trip_id/activities(.:format)          activities#create
   new_trip_activity GET    /trips/:trip_id/activities/new(.:format)      activities#new
  edit_trip_activity GET    /trips/:trip_id/activities/:id/edit(.:format) activities#edit
       trip_activity GET    /trips/:trip_id/activities/:id(.:format)      activities#show
                     PATCH  /trips/:trip_id/activities/:id(.:format)      activities#update
                     PUT    /trips/:trip_id/activities/:id(.:format)      activities#update
                     DELETE /trips/:trip_id/activities/:id(.:format)      activities#destroy
               trips GET    /trips(.:format)                              trips#index
                     POST   /trips(.:format)                              trips#create
            new_trip GET    /trips/new(.:format)                          trips#new
           edit_trip GET    /trips/:id/edit(.:format)                     trips#edit
                trip GET    /trips/:id(.:format)                          trips#show
                     PATCH  /trips/:id(.:format)                          trips#update
                     PUT    /trips/:id(.:format)                          trips#update
                     DELETE /trips/:id(.:format)                          trips#destroy

还有我的事件 Controller .rb -

  before_action :set_activity, only: %i[show update edit destroy]

  def edit; end

  def update
    dates = calculate_datetimes(params[:date_range])
    @activity.assign_attributes(name: params[:name],
                                summary: params[:summary],
                                start_datetime: dates[0],
                                end_datetime: dates[1])
    if @activity.save
      flash[:success] = 'Activity successfully updated'
      redirect_to(@trip)
    else
      set_humanized_daterange
      render :edit
    end
  end

  private 

  def set_activity
    @activity = Activity.find(params[:id])
  end

tl;博士 - 我应该如何为嵌套资源设置我的 form_with，为什么这个表单认为我想使用 activity_path ?理想情况下，我想将此表单移动到部分表单中，并为我的 #new 和 #edit 操作使用相同的表单。

Answer 1

尝试分别指定模型和网址:

form_with(model: @activity, url: [@trip, @activity])

根据文档， url 的值是“类似于传递给 url_for 或 link_to 的值”，因此使用数组应该可以工作。

这也适用于浅嵌套，因为数组是压缩的。