2

Railsプログラミングは初めてで、オブジェクトの基本的な保存を試みています。私のコントローラーのコードは次のとおりです。

    def create 
       @subject = Subject.new
       @subject.resource_id = params[:subject][:resource_id]
       @subject.student_id = params[:subject][:student_id]
       @subject.baseid = params[:subject][:baseid]
       @subject = params[:subject]

       respond_to do |format|  # line 50
         if @subject.save      # line 51
            format.html { redirect_to @subject, :notice => 'Subject was successfully created.' }
            format.json { render :json => @subject, :status => :created, :location => @subject }
         else
            format.html { render :action => "new" }
            format.json { render :json => @subject.errors, :status => :unprocessable_entity }
         end
       end
    end

そして、私のビューコードは次のようになります:

    <%= form_for(@subject) do |f| %>
      <% if @subject.errors.any? %>
        <div id="error_explanation">
          <h2><%= pluralize(@subject.errors.count, "error") %> prohibited this subject from being saved:</h2>

          <ul>
          <% @subject.errors.full_messages.each do |msg| %>
            <li><%= msg %></li>
          <% end %>
          </ul>
        </div>
      <% end %>

      <div class="field">
        <%= f.label :Subject %><br />
        <%= f.text_field :name %>
      </div>
      <div class="field">
        <%= f.label :baseid %><br />
        <%= f.number_field :baseid %>
      </div>
      <div class="field">
        <%= f.label :Resource %><br />
        <%= select(:subject, :resource_id, Resource.all.collect { |r| [ r.title, r.id ] }, { :prompt => true }) %>
      </div>
      <div class="field">
        <%= f.label :Student %><br />
        <%= select(:subject, :student_id, Student.all.collect { |s| [s.name, s.id ] }, { :include_blank => true }) %>
      </div>
      <div class="field">
        <%= f.label :Graded? %><br />
        <%= f.check_box :graded %>
      </div>
      <div class="field">
        <%= f.label :Student_scored %><br />
        <%= f.check_box :studentupdate %>
      </div>
      <div class="field">
        <%= f.label  :Monday %><br />
        <%= f.check_box :AssignOnMonday %>
      </div>
      <div class="field">
        <%= f.label :Tuesday %><br />
        <%= f.check_box :AssignOnTuesday %>
      </div>
      <div class="field">
        <%= f.label :Wednesday %><br />
        <%= f.check_box :AssignOnWednesday %>
      </div>
      <div class="field">
        <%= f.label :Thursday %><br />
        <%= f.check_box :AssignOnThursday %>
      </div>
      <div class="field">
        <%= f.label :Friday %><br />
        <%= f.check_box :AssignOnFriday %>
      </div>
      <div class="actions">
        <%= f.submit %>
      </div>
    <% end %>

保存しようとすると、「if @subject.save」という行でエラーが発生し、「save」は未定義のメソッドです。他のオブジェクトを保存しても問題ありません。コントローラーとビューの間の相互作用である必要がありますが、私はそれを理解することはできません。

生成された HTML は次のようになります。

{"utf8"=>"✓",
 "authenticity_token"=>"6BNo+WhSXreJekQvRo10DSp46LBNPkxskBREZr41q+Y=",
 "subject"=>{"name"=>"ttesting",
 "baseid"=>"11",
 "resource_id"=>"1",
 "student_id"=>"1",
 "graded"=>"1",
 "studentupdate"=>"0",
 "AssignOnMonday"=>"1",
 "AssignOnTuesday"=>"1",
 "AssignOnWednesday"=>"1",
 "AssignOnThursday"=>"0",
 "AssignOnFriday"=>"0"},
 "commit"=>"Create Subject"}

そしてトレースダンプ:

app/controllers/subjects_controller.rb:51:in `block in create'
actionpack (3.2.2) lib/action_controller/metal/mime_responds.rb:278:in `call'
actionpack (3.2.2) lib/action_controller/metal/mime_responds.rb:278:in `retrieve_collector_from_mimes'
actionpack (3.2.2) lib/action_controller/metal/mime_responds.rb:194:in `respond_to'
app/controllers/subjects_controller.rb:50:in `create'
actionpack (3.2.2) lib/action_controller/metal/implicit_render.rb:4:in `send_action'
actionpack (3.2.2) lib/abstract_controller/base.rb:167:in `process_action'
actionpack (3.2.2) lib/action_controller/metal/rendering.rb:10:in `process_action'
actionpack (3.2.2) lib/abstract_controller/callbacks.rb:18:in `block in process_action'
activesupport (3.2.2) lib/active_support/callbacks.rb:414:in `_run__4186951750656382860__process_action__4279552811083519369__callbacks'
activesupport (3.2.2) lib/active_support/callbacks.rb:405:in `__run_callback'
activesupport (3.2.2) lib/active_support/callbacks.rb:385:in `_run_process_action_callbacks'
activesupport (3.2.2) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (3.2.2) lib/abstract_controller/callbacks.rb:17:in `process_action'
actionpack (3.2.2) lib/action_controller/metal/rescue.rb:29:in `process_action'
actionpack (3.2.2) lib/action_controller/metal/instrumentation.rb:30:in `block in process_action'
activesupport (3.2.2) lib/active_support/notifications.rb:123:in `block in instrument'
activesupport (3.2.2) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (3.2.2) lib/active_support/notifications.rb:123:in `instrument'
actionpack (3.2.2) lib/action_controller/metal/instrumentation.rb:29:in `process_action'
actionpack (3.2.2) lib/action_controller/metal/params_wrapper.rb:205:in `process_action'
activerecord (3.2.2) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
actionpack (3.2.2) lib/abstract_controller/base.rb:121:in `process'
actionpack (3.2.2) lib/abstract_controller/rendering.rb:45:in `process'
actionpack (3.2.2) lib/action_controller/metal.rb:203:in `dispatch'
actionpack (3.2.2) lib/action_controller/metal/rack_delegation.rb:14:in `dispatch'
actionpack (3.2.2) lib/action_controller/metal.rb:246:in `block in action'
actionpack (3.2.2) lib/action_dispatch/routing/route_set.rb:67:in `call'
actionpack (3.2.2) lib/action_dispatch/routing/route_set.rb:67:in `dispatch'
actionpack (3.2.2) lib/action_dispatch/routing/route_set.rb:30:in `call'
journey (1.0.3) lib/journey/router.rb:68:in `block in call'
journey (1.0.3) lib/journey/router.rb:56:in `each'
journey (1.0.3) lib/journey/router.rb:56:in `call'
actionpack (3.2.2) lib/action_dispatch/routing/route_set.rb:594:in `call'
actionpack (3.2.2) lib/action_dispatch/middleware/best_standards_support.rb:17:in `call'
rack (1.4.1) lib/rack/etag.rb:23:in `call'
rack (1.4.1) lib/rack/conditionalget.rb:35:in `call'
actionpack (3.2.2) lib/action_dispatch/middleware/head.rb:14:in `call'
actionpack (3.2.2) lib/action_dispatch/middleware/params_parser.rb:21:in `call'
actionpack (3.2.2) lib/action_dispatch/middleware/flash.rb:242:in `call'
rack (1.4.1) lib/rack/session/abstract/id.rb:205:in `context'
rack (1.4.1) lib/rack/session/abstract/id.rb:200:in `call'
actionpack (3.2.2) lib/action_dispatch/middleware/cookies.rb:338:in `call'
activerecord (3.2.2) lib/active_record/query_cache.rb:64:in `call'
activerecord (3.2.2) lib/active_record/connection_adapters/abstract/connection_pool.rb:443:in `call'
actionpack (3.2.2) lib/action_dispatch/middleware/callbacks.rb:28:in `block in call'
activesupport (3.2.2) lib/active_support/callbacks.rb:405:in `_run__665871749096871788__call__3768009419737595332__callbacks'
activesupport (3.2.2) lib/active_support/callbacks.rb:405:in `__run_callback'
activesupport (3.2.2) lib/active_support/callbacks.rb:385:in `_run_call_callbacks'
activesupport (3.2.2) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (3.2.2) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
actionpack (3.2.2) lib/action_dispatch/middleware/reloader.rb:65:in `call'
actionpack (3.2.2) lib/action_dispatch/middleware/remote_ip.rb:31:in `call'
actionpack (3.2.2) lib/action_dispatch/middleware/debug_exceptions.rb:16:in `call'
actionpack (3.2.2) lib/action_dispatch/middleware/show_exceptions.rb:56:in `call'
railties (3.2.2) lib/rails/rack/logger.rb:26:in `call_app'
railties (3.2.2) lib/rails/rack/logger.rb:16:in `call'
actionpack (3.2.2) lib/action_dispatch/middleware/request_id.rb:22:in `call'
rack (1.4.1) lib/rack/methodoverride.rb:21:in `call'
rack (1.4.1) lib/rack/runtime.rb:17:in `call'
activesupport (3.2.2) lib/active_support/cache/strategy/local_cache.rb:72:in `call'
rack (1.4.1) lib/rack/lock.rb:15:in `call'
actionpack (3.2.2) lib/action_dispatch/middleware/static.rb:61:in `call'
railties (3.2.2) lib/rails/engine.rb:479:in `call'
railties (3.2.2) lib/rails/application.rb:220:in `call'
rack (1.4.1) lib/rack/content_length.rb:14:in `call'
railties (3.2.2) lib/rails/rack/log_tailer.rb:14:in `call'
rack (1.4.1) lib/rack/handler/webrick.rb:59:in `service'
/Users/Lon/.rbenv/versions/1.9.3-p125/lib/ruby/1.9.1/webrick/httpserver.rb:138:in `service'
/Users/Lon/.rbenv/versions/1.9.3-p125/lib/ruby/1.9.1/webrick/httpserver.rb:94:in `run'
/Users/Lon/.rbenv/versions/1.9.3-p125/lib/ruby/1.9.1/webrick/server.rb:191:in `block in start_thread'

提案をいただければ幸いです。

ありがとう、

ロン


Google マップにはいくつのズーム レベルがありますか

私の知る限り、MKMapview無限のズームレベルがあります。任意の距離でズームインおよびズームアウトできます。

MKMapviewAndroid で働いている私の友人は、ズーム レベルが 10であると言っています。

どちらが正しいですか?

ここにドキュメントがあります

4

1 に答える 1

2

この行:

 @subject = params[:subject]

あなたのバグを引き起こします。@subject を上書きしています。サブジェクトではなく、ハッシュになりました。したがって、それに対して save を呼び出すことはできません

に置き換えます

@subject.attributes = params[:subject]

また、リクエストごとまたはユーザーごとに一括割り当てを承認する方法については、RailsCast Dynamic Mass Assignment を参照してください。

于 2012-08-06T04:19:37.190 に答える