我正在研究包含物品的todolist。我正在我的用户#show中加载部分但收到此错误：
在32毫秒内完成500内部服务器错误
NameError - undefined local variable or method `item' for #<#<Class:0x007f8205179fd8>:0x007f8207517e90>:
app/views/items/_item.html.erb:1:in `_app_views_items__item_html_erb___4608125545228137447_70098222191840'
actionview (4.2.0) lib/action_view/template.rb:145:in `block in render'
activesupport (4.2.0) lib/active_support/notifications.rb:166:in `instrument'
actionview (4.2.0) lib/action_view/template.rb:333:in `instrument'
actionview (4.2.0) lib/action_view/template.rb:143:in `render'
actionview (4.2.0) lib/action_view/renderer/partial_renderer.rb:339:in `render_partial'
actionview (4.2.0) lib/action_view/renderer/partial_renderer.rb:310:in `block in render'
actionview (4.2.0) lib/action_view/renderer/abstract_renderer.rb:39:in `block in instrument'
activesupport (4.2.0) lib/active_support/notifications.rb:164:in `block in instrument'
activesupport (4.2.0) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (4.2.0) lib/active_support/notifications.rb:164:in `instrument'
actionview (4.2.0) lib/action_view/renderer/abstract_renderer.rb:39:in `instrument'
actionview (4.2.0) lib/action_view/renderer/partial_renderer.rb:309:in `render'
actionview (4.2.0) lib/action_view/renderer/renderer.rb:47:in `render_partial'
actionview (4.2.0) lib/action_view/renderer/renderer.rb:21:in `render'
actionview (4.2.0) lib/action_view/helpers/rendering_helper.rb:32:in `render'
app/views/users/show.html.erb:19:in `_app_views_users_show_html_erb___1022675542096665118_70098203758600'
actionview (4.2.0) lib/action_view/template.rb:145:in `block in render'
activesupport (4.2.0) lib/active_support/notifications.rb:166:in `instrument'
actionview (4.2.0) lib/action_view/template.rb:333:in `instrument'
actionview (4.2.0) lib/action_view/template.rb:143:in `render'
actionview (4.2.0) lib/action_view/renderer/template_renderer.rb:54:in `block (2 levels) in render_template'
actionview (4.2.0) lib/action_view/renderer/abstract_renderer.rb:39:in `block in instrument'
activesupport (4.2.0) lib/active_support/notifications.rb:164:in `block in instrument'
activesupport (4.2.0) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (4.2.0) lib/active_support/notifications.rb:164:in `instrument'
actionview (4.2.0) lib/action_view/renderer/abstract_renderer.rb:39:in `instrument'
actionview (4.2.0) lib/action_view/renderer/template_renderer.rb:53:in `block in render_template'
actionview (4.2.0) lib/action_view/renderer/template_renderer.rb:61:in `render_with_layout'
actionview (4.2.0) lib/action_view/renderer/template_renderer.rb:52:in `render_template'
actionview (4.2.0) lib/action_view/renderer/template_renderer.rb:14:in `render'
actionview (4.2.0) lib/action_view/renderer/renderer.rb:42:in `render_template'
actionview (4.2.0) lib/action_view/renderer/renderer.rb:23:in `render'
actionview (4.2.0) lib/action_view/rendering.rb:100:in `_render_template'
actionpack (4.2.0) lib/action_controller/metal/streaming.rb:217:in `_render_template'
actionview (4.2.0) lib/action_view/rendering.rb:83:in `render_to_body'
actionpack (4.2.0) lib/action_controller/metal/rendering.rb:32:in `render_to_body'
actionpack (4.2.0) lib/action_controller/metal/renderers.rb:37:in `render_to_body'
actionpack (4.2.0) lib/abstract_controller/rendering.rb:25:in `render'
actionpack (4.2.0) lib/action_controller/metal/rendering.rb:16:in `render'
actionpack (4.2.0) lib/action_controller/metal/instrumentation.rb:41:in `block (2 levels) in render'
activesupport (4.2.0) lib/active_support/core_ext/benchmark.rb:12:in `block in ms'
/Users/ericpark/.rvm/rubies/ruby-2.2.0/lib/ruby/2.2.0/benchmark.rb:303:in `realtime'
activesupport (4.2.0) lib/active_support/core_ext/benchmark.rb:12:in `ms'
actionpack (4.2.0) lib/action_controller/metal/instrumentation.rb:41:in `block in render'
actionpack (4.2.0) lib/action_controller/metal/instrumentation.rb:84:in `cleanup_view_runtime'
activerecord (4.2.0) lib/active_record/railties/controller_runtime.rb:25:in `cleanup_view_runtime'
actionpack (4.2.0) lib/action_controller/metal/instrumentation.rb:40:in `render'
actionpack (4.2.0) lib/action_controller/metal/implicit_render.rb:10:in `default_render'
actionpack (4.2.0) lib/action_controller/metal/implicit_render.rb:5:in `send_action'
actionpack (4.2.0) lib/abstract_controller/base.rb:198:in `process_action'
actionpack (4.2.0) lib/action_controller/metal/rendering.rb:10:in `process_action'
actionpack (4.2.0) lib/abstract_controller/callbacks.rb:20:in `block in process_action'
activesupport (4.2.0) lib/active_support/callbacks.rb:117:in `call'
activesupport (4.2.0) lib/active_support/callbacks.rb:151:in `block in halting_and_conditional'
activesupport (4.2.0) lib/active_support/callbacks.rb:234:in `block in halting'
activesupport (4.2.0) lib/active_support/callbacks.rb:234:in `block in halting'
activesupport (4.2.0) lib/active_support/callbacks.rb:169:in `block in halting'
activesupport (4.2.0) lib/active_support/callbacks.rb:169:in `block in halting'
activesupport (4.2.0) lib/active_support/callbacks.rb:169:in `block in halting'
activesupport (4.2.0) lib/active_support/callbacks.rb:92:in `_run_callbacks'
activesupport (4.2.0) lib/active_support/callbacks.rb:734:in `_run_process_action_callbacks'
activesupport (4.2.0) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (4.2.0) lib/abstract_controller/callbacks.rb:19:in `process_action'
actionpack (4.2.0) lib/action_controller/metal/rescue.rb:29:in `process_action'
actionpack (4.2.0) lib/action_controller/metal/instrumentation.rb:31:in `block in process_action'
activesupport (4.2.0) lib/active_support/notifications.rb:164:in `block in instrument'
activesupport (4.2.0) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (4.2.0) lib/active_support/notifications.rb:164:in `instrument'
actionpack (4.2.0) lib/action_controller/metal/instrumentation.rb:30:in `process_action'
actionpack (4.2.0) lib/action_controller/metal/params_wrapper.rb:250:in `process_action'
activerecord (4.2.0) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
actionpack (4.2.0) lib/abstract_controller/base.rb:137:in `process'
actionview (4.2.0) lib/action_view/rendering.rb:30:in `process'
actionpack (4.2.0) lib/action_controller/metal.rb:195:in `dispatch'
actionpack (4.2.0) lib/action_controller/metal/rack_delegation.rb:13:in `dispatch'
actionpack (4.2.0) lib/action_controller/metal.rb:236:in `block in action'
actionpack (4.2.0) lib/action_dispatch/routing/route_set.rb:73:in `dispatch'
actionpack (4.2.0) lib/action_dispatch/routing/route_set.rb:42:in `serve'
actionpack (4.2.0) lib/action_dispatch/journey/router.rb:43:in `block in serve'
actionpack (4.2.0) lib/action_dispatch/journey/router.rb:30:in `serve'
actionpack (4.2.0) lib/action_dispatch/routing/route_set.rb:802:in `call'
warden (1.2.3) lib/warden/manager.rb:35:in `block in call'
warden (1.2.3) lib/warden/manager.rb:34:in `call'
rack (1.6.1) lib/rack/etag.rb:24:in `call'
rack (1.6.1) lib/rack/conditionalget.rb:25:in `call'
rack (1.6.1) lib/rack/head.rb:13:in `call'
actionpack (4.2.0) lib/action_dispatch/middleware/params_parser.rb:27:in `call'
actionpack (4.2.0) lib/action_dispatch/middleware/flash.rb:260:in `call'
rack (1.6.1) lib/rack/session/abstract/id.rb:225:in `context'
rack (1.6.1) lib/rack/session/abstract/id.rb:220:in `call'
actionpack (4.2.0) lib/action_dispatch/middleware/cookies.rb:560:in `call'
activerecord (4.2.0) lib/active_record/query_cache.rb:36:in `call'
activerecord (4.2.0) lib/active_record/connection_adapters/abstract/connection_pool.rb:647:in `call'
activerecord (4.2.0) lib/active_record/migration.rb:378:in `call'
actionpack (4.2.0) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'
activesupport (4.2.0) lib/active_support/callbacks.rb:88:in `_run_callbacks'
activesupport (4.2.0) lib/active_support/callbacks.rb:734:in `_run_call_callbacks'
activesupport (4.2.0) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (4.2.0) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
actionpack (4.2.0) lib/action_dispatch/middleware/reloader.rb:73:in `call'
actionpack (4.2.0) lib/action_dispatch/middleware/remote_ip.rb:78:in `call'
better_errors (2.1.1) lib/better_errors/middleware.rb:84:in `protected_app_call'
better_errors (2.1.1) lib/better_errors/middleware.rb:79:in `better_errors_call'
better_errors (2.1.1) lib/better_errors/middleware.rb:57:in `call'
actionpack (4.2.0) lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call'
web-console (2.1.2) lib/web_console/middleware.rb:37:in `call'
actionpack (4.2.0) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
railties (4.2.0) lib/rails/rack/logger.rb:38:in `call_app'
railties (4.2.0) lib/rails/rack/logger.rb:20:in `block in call'
activesupport (4.2.0) lib/active_support/tagged_logging.rb:68:in `block in tagged'
activesupport (4.2.0) lib/active_support/tagged_logging.rb:26:in `tagged'
activesupport (4.2.0) lib/active_support/tagged_logging.rb:68:in `tagged'
railties (4.2.0) lib/rails/rack/logger.rb:20:in `call'
actionpack (4.2.0) lib/action_dispatch/middleware/request_id.rb:21:in `call'
rack (1.6.1) lib/rack/methodoverride.rb:22:in `call'
rack (1.6.1) lib/rack/runtime.rb:18:in `call'
activesupport (4.2.0) lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'
rack (1.6.1) lib/rack/lock.rb:17:in `call'
actionpack (4.2.0) lib/action_dispatch/middleware/static.rb:113:in `call'
rack (1.6.1) lib/rack/sendfile.rb:113:in `call'
railties (4.2.0) lib/rails/engine.rb:518:in `call'
railties (4.2.0) lib/rails/application.rb:164:in `call'
rack (1.6.1) lib/rack/lock.rb:17:in `call'
rack (1.6.1) lib/rack/content_length.rb:15:in `call'
rack (1.6.1) lib/rack/handler/webrick.rb:89:in `service'
/Users/ericpark/.rvm/rubies/ruby-2.2.0/lib/ruby/2.2.0/webrick/httpserver.rb:138:in `service'
/Users/ericpark/.rvm/rubies/ruby-2.2.0/lib/ruby/2.2.0/webrick/httpserver.rb:94:in `run'
/Users/ericpark/.rvm/rubies/ruby-2.2.0/lib/ruby/2.2.0/webrick/server.rb:294:in `block in start_thread'
以下是我的一些代码： _item.html.erb
<% if item.persisted? %>
<div id="item-<%=item.id%>" class="tasks">
<%= link_to "", [item.user, item], method: :delete, remote: true, class: 'glyphicon glyphicon-ok' %>
<%= item.name %>
<div class="time">
<% if item.days_left > 2 %>
<small class="text-uppercase time-left glyphicon glyphicon-time"> <%= pluralize(item.days_left, "day") %></small>
<% else %>
<small class="text-uppercase time-left-short glyphicon glyphicon-time"> <%= pluralize(item.days_left, "day") %></small>
<% end %>
</div>
</div>
<br>
<% end %>
物品管制员： class ItemsController＆lt; ApplicationController中
respond_to :html, :js
def new
@user = User.find(params[:user_id])
@item = Item.new
end
def create
@user = User.find(params[:user_id])
@item = Item.new(item_params)
@item.user_id = @user.id
if @item.save
flash[:notice] = "Task was saved."
else
flash[:error] = "There was an error saving the task. Please try again."
end
end
def show
@user = User.find(params[:user_id])
@item = Item.find(params[:id])
end
def destroy
@user = User.find(params[:user_id])
@item = Item.find(params[:id])
if @item.destroy
flash[:notice] = "Good job, completing that task!"
else
flash[:error] = "Task couldn't be deleted. Try again."
end
end
private
def item_params
params.require(:item).permit(:name, :user_id)
end
end
因为部分只是通过项目列出，我不认为它与路线有任何关系。如果_item.html.erb部分已经在items目录中，为什么它是未定义的？如果我是正确的，items_controller不需要定义类变量项？这是一个正确的假设吗？
答案 0 :(得分：0)
将 _item.html.erb 更改为：
<% if @item.persisted? %>
....
<% end %>