如何使用simple_form显示完整的错误消息？

Question

Instead of short error messages like can't be blank I'd like to have full error messages like Url can't be blank . How can I do this with simple_form? (just for one field or one form only, not for all forms)

Answer 1

There is error message YAML which you can update to create custom error messages for forms, any form gem you happen to be using or none at all. Look for it in config/locales/en.yml. Caveat: The ymls are autoloaded and there's an entire set of non-obvious behaviors they have, but the form YAML setup is pretty intuitive. When editing, do not use tabs and be careful not to permit any extra spaces anywhere or YAML parse will fail at runtime.

Here's a snippet from the activerecord/form-relevant area in my en.yml:

en.yml

  activerecord: 
    errors: 
      models: 
        article: 
          attributes: 
            category: 
              blank: "You must select a category for this post."
            author: 
              blank: "You must enter an author name."
            title: 
              blank: "A title is required."
            content: 

There is a YAML file that is installed with simple_form, simple_form.en.yml in the same directory. I haven't used that one, but it might be more intuitive/easier to use but will only apply to simple_form actions.

Default version simple_form.en.yml

en:
  simple_form:
    "yes": 'Yes'
    "no": 'No'
    required:
      text: 'required'
      mark: '*'
      # You can uncomment the line below if you need to overwrite the whole required html.
      # When using html, text and mark won't be used.
      # html: '<abbr title="required">*</abbr>'
    error_notification:
      default_message: "Please review the problems below:"
    # Examples
    # labels:
    #   defaults:
    #     password: 'Password'
    #   user:
    #     new:
    #       email: 'E-mail to sign in.'
    #     edit:
    #       email: 'E-mail.'
    # hints:
    #   defaults:
    #     username: 'User name to sign in.'
    #     password: 'No special characters, please.'
    # include_blanks:
    #   defaults:
    #     age: 'Rather not say'
    # prompts:
    #   defaults:
    #     age: 'Select your age'

Here's a YAML linter (you'll need it): http://www.yamllint.com/

The YAML translation files are the answer, but it's a clunky implementation and real pain to get right. Please follow up if you have any issues with it.

Answer 2

You can customize your locale-files correspondingly or define custom message inside model at validation section. Here are some possibilities for a solution.