我是 Rails 新手，目前正在开发一个博客。我想知道是否有关于如何使用 Acts 作为可注释线程的教程，因为从 GitHub 使用的唯一说明是添加acts_as_commentable到您的模型中。
- 我应该如何为新评论创建表单？
- 如何从模型中检索所有评论？
- 如何配置路由以显示评论？
- 如何修改我的控制器以使此功能可用？
class Comment < ActiveRecord::Base
acts_as_nested_set :scope => [:commentable_id, :commentable_type]
#attr_accessible :commentable, :body, :user_id
validates :body, :presence => true
validates :user, :presence => true
# NOTE: install the acts_as_votable plugin if you
# want user to vote on the quality of comments.
#acts_as_votable
belongs_to :commentable, :polymorphic => true
# NOTE: Comments belong to a user
belongs_to :user
# Helper class method that allows you to build a comment
# by passing a commentable object, a user_id, and comment text
# example in readme
def self.build_from(obj, user_id, comment)
new \
:commentable => obj,
:body => comment,
:user_id => user_id
end
#helper method to check if a comment has children
def has_children?
self.children.any?
end
# Helper class method to lookup all comments assigned
# to all commentable types for a given user.
scope :find_comments_by_user, lambda { |user|
where(:user_id => user.id).order('created_at DESC')
}
# Helper class method to look up all comments for
# commentable class name and commentable id.
scope :find_comments_for_commentable, lambda { |commentable_str, commentable_id|
where(:commentable_type => commentable_str.to_s, :commentable_id => commentable_id).order('created_at DESC')
}
# Helper class method to look up a commentable object
# given the commentable class name and id
def self.find_commentable(commentable_str, commentable_id)
commentable_str.constantize.find(commentable_id)
end
end