nested_form笔记

1. 安装gem包

gem 'nested_form'

增加jquery效果,在application.js中添加

//= require jquery_nested_form

执行bundle install

2. 新建两个Model

Event

classCreateEvents

def  changecreate_table:events  do |t|

    t.string:title

    t.text:expression

    t.timestamps null:false

end

end

end

Task

classCreateTasks

        def   changecreate_table:tasks  do |t|

                t.integer:event_id

                t.text:name

                t.text:dothing

                t.timestamps null:false

        end

end

end

3. 确定Model之间的关系

classEvent

    has_many:tasks

    accepts_nested_attributes_for:tasks,:allow_destroy=>true,:reject_if=>:all_blank

end

classTask

    belongs_to:event

end

4. 修改controller

def  event_params

        params.require(:event).permit(:title,:expression,:tasks_attributes=>[:id,:name,:dothing,:_destroy])

end

5. 修改view

<%= nested_form_for(@event) do |f| %>  

<% if @event.errors.any? %>

<%= pluralize(@event.errors.count, "error") %> prohibited this event from being saved:

<% @event.errors.full_messages.each do |message| %>
• <%= message %>

<% end %>

<% end %>

<%= f.label :title %>

<%= f.text_field :title %>

<%= f.label :expression %>

<%= f.text_area :expression %>