Question

I’m trying to pass a model attribute to a view, after successfully setting it to a new value from inside an action in my controller. But this variable is always nil by the time it gets to the view, so I can’t use it to conditionally display stuff. I should add that this attribute is not a field in the database. What am I missing/doing wrong?

Here is the code in my model:

attr_accessor :mode  #getter def mode  @mode end  #setter def mode=(val)  @mode = val end 

…in the controller:

@report.mode = 't' redirect_to edit_report_path(@report) 

…and in my view:

<%= build_report(@report.mode) %> 

…but this helper method never gets the variable I just set in the controller. It is nil. What gives? Clearly I’m missing something basic here because this seems like it should be straightforward. Any insight would be greatly appreciated. Thanks.

Answer 1

edit_report_path generates a URL with the ID of @report in it.

redirect_to essentially creates a whole new request, and goes to that URL. When it gets to edit, all it has is the ID. Usually that’s fine – it looks up the object and keeps going, but of course it’s not going to have the non-db field you set.

There are a couple ways to fix this. You can use :render instead to get to the edit page – then @report will have the field set.

@report.mode = 't' render :action => edit and return 

Or, you can make mode a database field.