Ruby-on-rails rails，simple_form，如何在页面加载时设置集合的选定索引？
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rails, simple_form, how to set selected index of a collection when page loaded?
提问by simo
I am using simple_form gem, I have a countries collection, it work fine when I select the country, and updated record will have the country id stored, but, when I try to edit the record, the chosen country is not selected by default at edit form.
我正在使用 simple_form gem，我有一个国家集合，当我选择国家时它工作正常，更新的记录将存储国家 ID，但是，当我尝试编辑记录时，默认情况下未选择所选国家编辑表格。
Here is the code at edit form:
这是编辑表单中的代码：
= f.input :country_id, :collection => all_countries
Shouldn't simple_form view the selected country from the db ?
simple_form 不应该从 db 中查看选定的国家吗？
回答by Manish Shrivastava
Have you tried to use the :selected => option?
您是否尝试过使用 :selected => 选项？
:selected => selected_country_id
So,
所以，
= f.input :country_id, :collection => all_countries, :selected => selected_country_id
This will work perfectly !!!
这将完美地工作！！！
Cheers!
干杯!
回答by genkilabs
I know this has been answered, but I came here looking for a similar solution for a collection of check boxes. For posterity, here's how you do it:
我知道这已经得到了回答，但我来到这里是为一组复选框寻找类似的解决方案。对于后代，这是您的方法：
<%= f.input :country_ids, :as => :check_boxes, :collection => [['USA', :USA], ['Japan', :JPN]], :checked => [:JPN], :include_hidden => false %>
Hope this helps someone.
希望这可以帮助某人。
