ruby-on-rails - 未定义的方法 `group_by_day' - rails 3.2

Question

我想使用 chartkick 制作用户注册数量(每天)的折线图，这是一个简单的一行代码，但它给出了一个错误

`undefined method `group_by_day' for #<Class:0x00000004b4fbf0>`

在我看来我有

<%= line_chart User.group_by_day(:created_at).count %>

错误日志:

Rendered admin/dashboards/index.html.erb within layouts/application (145.2ms)
Completed 500 Internal Server Error in 1018ms

NoMethodError - undefined method `group_by_day' for #<Class:0x00000004b4fbf0>:
  activerecord (3.2.14) lib/active_record/dynamic_matchers.rb:55:in `method_missing'
  app/views/admin/dashboards/index.html.erb:38:in `_app_views_admin_dashboards_index_html_erb___3330517857505238097_39214860'
  actionpack (3.2.14) lib/action_view/template.rb:145:in `block in render'
  activesupport (3.2.14) lib/active_support/notifications.rb:125:in `instrument'
  actionpack (3.2.14) lib/action_view/template.rb:143:in `render'
  actionpack (3.2.14) lib/action_view/renderer/template_renderer.rb:48:in `block (2 levels) in render_template'
  actionpack (3.2.14) lib/action_view/renderer/abstract_renderer.rb:38:in `block in instrument'
  activesupport (3.2.14) lib/active_support/notifications.rb:123:in `block in instrument'
  activesupport (3.2.14) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
  activesupport (3.2.14) lib/active_support/notifications.rb:123:in `instrument'
  actionpack (3.2.14) lib/action_view/renderer/abstract_renderer.rb:38:in `instrument'

Answer 1

要支持 group_by_day，您需要捆绑另一个 gem:groupdate来自 Chartkick 的同一作者。