我有一个表单，它从多个来源提取数据以智能地预填充表单中的一些默认值。I would like to also prefill a "visit_price" text box that will be editable when the "visit_type" drop down is selected. 此下拉列表是一个 grouped_collection_select，它通过名称搜索字段通过 jquery 进行调整（根据此和此railscast 视频）
下面是到目前为止的表单视图、模型关联和咖啡脚本。我还包括了相关的 html 输出。
编辑： 要清楚，我不确定如何获取与从下拉列表中选择的客户价格相关的价格。
访问块表单视图
<%= form_for(@visit_block) do |f| %>
<div class="controls controls-row">
<div class="form-inputs">
<%= f.text_field :client_name, data: {autocomplete_source: current_user.clients.order(:last_name).map(&:last_name)} %>
</div>
<div class="form-inputs">
<%= f.grouped_collection_select :visit_type, current_user.clients.order(:last_name), :client_prices, :last_name, :visit_type, :visit_type, include_blank: true %>
<%= f.text_field :visit_price %>
</div>
</div>
<div class="form-actions">
<%= f.button :submit %>
</div>
<% end %>
楷模
class VisitBlock < ActiveRecord::Base
attr_accessible :visit_price, :visit_type, :client_id
belongs_to :client
def client_name
client.try(:last_name)
end
def client_name=(last_name)
self.client = Client.find_by_last_name(last_name) if last_name.present?
end
end
class Client < ActiveRecord::Base
attr_accessible :active, :address_1, :address_2, :city, :email, :first_name, :last_name, :state, :user_id, :zip, :client_prices_attributes
has_many :client_prices, :dependent => :destroy
end
class ClientPrice < ActiveRecord::Base
attr_accessible :client_id, :price, :visit_type, :id, :default_price_id, :custom, :_destroy
belongs_to :client
belongs_to :default_price
end
Coffeescript（到目前为止）
jQuery ->
$('#visit_block_client_name').autocomplete
source: $('#visit_block_client_name').data('autocomplete-source')
visit_types = $("#visit_block_visit_type").html()
console.log visit_types
$("#visit_block_client_name").keyup ->
client_name = visit_block_client_name.value
options = $(visit_types).filter("optgroup[label=" + client_name + "]").html()
console.log options
if options
$("#visit_block_visit_type").html options
else
$("#visit_block_visit_type").empty()
$("#ui-id-1").click ->
client_name = visit_block_client_name.value
options = $(visit_types).filter("optgroup[label=" + client_name + "]").html()
console.log options
if options
$("#visit_block_visit_type").html options
else
$("#visit_block_visit_type").empty()
HTML 输出（到目前为止）
<h1>New visit_block</h1>
<form accept-charset="UTF-8" action="/visit_blocks" class="new_visit_block" id="new_visit_block" method="post"><div style="margin:0;padding:0;display:inline"><input name="utf8" type="hidden" value="✓" /><input name="authenticity_token" type="hidden" value="I4xbbvdswv18TtP4LWoZHo7udmABT0J/nvKEPLFfO5Q=" /></div>
<div class="controls controls-row">
<div class="form-inputs">
<input data-autocomplete-source="["Client1","Client2","Client3"]" id="visit_block_client_name" name="visit_block[client_name]" size="30" type="text" />
</div>
<div class="form-inputs">
<select id="visit_block_visit_type" name="visit_block[visit_type]"><option value=""></option>
<optgroup label="Client1">
<option value="morning">morning</option>
<option value="Morning weekday visit">Morning weekday visit</option>
</optgroup>
<optgroup label="Client2">
<option value="evening">evening</option>
<option value="Morning weekday visit">Morning weekday visit</option>
</optgroup>
<optgroup label="Client3">
<option value="afternoon">afternoon</option>
<option value="Morning weekday visit">Morning weekday visit</option>
</optgroup>
</select>
<input id="visit_block_visit_price" name="visit_block[visit_price]" size="30" type="text" />
</div>
</div>
<div class="form-actions">
<button name="button" type="submit">submit</button>
</div>
</form>