ruby-on-rails - 我无法更改标签类别

Question

我有一个导航面板。active如果单击它，我希望菜单项的类更改为。

%li= { :class => current_page?(admin_roles_path) ? 'active' : nil }
    = link_to "Roles", admin_roles_path

但我收到以下错误：

Haml::SyntaxError in Admin::Roles#index
Showing /sites/freshapp/app/views/layouts/_sidebar.html.haml where line #7 raised:

Illegal nesting: content can't be both given on the same line as %li and nested within it.

Answer 1

试试这个（你不需要=after %li）

%li{ :class => current_page?(admin_roles_path) ? 'active' : nil }
  = link_to "Roles", admin_roles_path

Answer 2

你不需要=你的%li，你有太多的空格/标签。（Haml 是一种嵌套语言，制表符/空格的数量很重要）。做这个：

%li{ :class => current_page?(admin_roles_path) ? 'active' : nil }
  = link_to "Roles", admin_roles_path

Answer 3

尝试这个

%li{ :class => "#{current_page?(admin_roles_path) ? 'active' : nil}"}
  = link_to "Roles", admin_roles_path