Basics questions on rails

Rails
1

Hello,

I started to use rails few weeks ago, and I have got basic question
about it.

  1. There is a way to keep my form filled, after submit it (for example
    if I get errors) ?

  2. I would like to create a ‘tree’ with my datas like ‘pages’ for
    example : a page has one children and belongs to a page. I added has_one
    and belongs_to to the model but it doesn’t work.

  3. My last question is about the models test. For example :
    validates_presence_of :name, :price, :description, :message =>
    ‘required’
    I would like to match this message in my controller to display it in a
    flash after…

Can you help me for these points please !

Cheers,
Vincent

2

On 1 Sep 2008, at 13:16, Vincent Pérès wrote:

Hello,

I started to use rails few weeks ago, and I have got basic question
about it.

  1. There is a way to keep my form filled, after submit it (for example
    if I get errors) ?

typically this is done by rendering the form. This is the common
if @foo.save
redirect_to …
else
render …
end

pattern which you should be able to find many examples off

  1. I would like to create a ‘tree’ with my datas like ‘pages’ for
    example : a page has one children and belongs to a page. I added
    has_one
    and belongs_to to the model but it doesn’t work.

‘it doesn’t work’ is too vague to be able to offer any real advice.
You’ll need to play with the class_name and foreign_key options (or
possible have a look at acts_as_tree)

  1. My last question is about the models test. For example :
    validates_presence_of :name, :price, :description, :message =>
    ‘required’
    I would like to match this message in my controller to display it in a
    flash after…

Assuming your record is @record then @record.errors contains
information about the failed validations (eg
@record.errors.full_messages. It can also do stuff like only give you
errors on certains fields etc…)

Fred

3

Hi.

If you assign the instance variable of your model to the view and use a
form
helper to build your forms, Rails will automatically assign a value if
it is
present in the instance object’s hash:

actionpack-2.1.0/lib/action_view/helpers/form_helper.rb, line 568:

(…)
=> 568 content_tag(“textarea”,
html_escape(options.delete(‘value’)
|| value_before_type_cast(object)), options)
(…)

The call to content tag tries to extract the value from the object or
deletes the tag if it is not present.

Where object is the object (model’s instance) that has been passed to
the
form_for helper method.

So, just follow Frederick’s advice and you should be good to go :slight_smile:

Marcelo.

On Mon, Sep 1, 2008 at 9:22 AM, Frederick C.
<[email protected]

4

Hello,

Thanks for your quick answers !

  1. I gave @record to my form_for and it was filled automatically.

  2. I will play again with belongs_to, has_one… I think it is basic
    configuration (page has a parent page id on each record)

  3. Perfect ! I found it thanks to your answer :
    Peak Obsession

Cheers,
Vincent