Validation in a "subform"

Rails
1

I’ve been following the rails/osx tutorial at

http://developer.apple.com/tools/rubyonrails.html

This develops a simple application with expenses and accounts.

Near the end of the tutorial, there is a view which allows expenses to
be added to an account.

This view has the “parent” @account rendered, then iterates throught
@account.expenses to display the existing accounts, then has a form.

<%= start_form_tag :action => ‘record’, :id => @account %>

On <%= date_select 'expense', 'paid_on', :order => [:month, :day, :year] %> to <%= text_field 'expense', 'payable_to', :size => 25 %> in the amount of $<%= text_field 'expense', 'amount', :size => 9 %>

<%= submit_tag 'Record!' %> <%= end_form_tag %>

Which then calls the record action in the controller:

def record
Account.find(params[:id]).expenses.create(params[:expense])
redirect_to :action => ‘show’, :id => params[:id]
end

and all is well. Very neat.

Except when you try to validate something in the new expense.

I’ve tried replacing the hand coded expense form with the partial in
/expenses/form (which has the “error_messages_for ‘expense’ line”),
but the validation messages don’t show up. The record is validated,
but the rendering of the error messages (and the nice red lines!)
don’t show.

I would be grateful for help! I wonder if it’s due to the page being
unable to find the expenses instance…

Thanks very much

Chris

2

it’s because this case is not handled in the “record” function. You
sould
have more something like:

def record
if Account.find(params[:id]).expenses.create(params[:expense])
redirect_to :action => ‘show’, :id => params[:id]
else
render :action => modifyAccount
end
end

the idea is to say “everything ok”? go there
Something wrong? display message

You can check how the scaffold do that.