Multi-dimensional hash/array as model attribute

Rails
1

I’m a Ruby and Rails newbie, trying to get out of PHP.

I have two AR models, Trip and Activity, where Trip has_many Activities.

I want to pull all the trips and load their associated activities as
attributes so that I can iterate over the trips, displaying each one and
it’s activities like so:

<% for trip in @trips %>

<%= trip.name%>    

<%= trip.summary%>

    <% for activity in trip.activities %>
  • <%= activity.name %>
    <%= @activity.description %>
    • <% end %>
<% end %>

I was able to hack this together in my controller:

@trips = Trip.find(:all)

@trips.each do |trip|
a = Activity.find_all_by_trip_id(trip.id)
a.each { |b| c = b.trip_id }
trip.activities = a if trip.id == c
end

It seems to load everything the way it should be, but I can’t get it to
display correctly, and there’s got to be a cleaner way to write this.

Any help would be greatly appreciated.

Thanks.

2

<%= trip.summary%>

@trips = Trip.find(:all)

@trips.each do |trip|
a = Activity.find_all_by_trip_id(trip.id)
a.each { |b| c = b.trip_id }
trip.activities = a if trip.id == c
end

It seems to load everything the way it should be, but I can’t get it to
display correctly, and there’s got to be a cleaner way to write this.

Assuming your tables are set up correctly (that is activities.trip_id
exists) you shouldn’t need anything more than the following in your
controller. That whole second block is redundant.

@trips = Trip.find(:all)

3

OK. I was able to get it to display correctly by changing
“trip.activities” to “trip[:activities]” in the view. I don’t quite
understand why that worked though…

And there’s still the issue of the controller code. There must be a Ruby
way to write that.

Thanks.

4

Thorsten M. wrote:

@trips = Trip.find(:all, :include => [:activities])
which would give slightly better db perdormance

Philip H. wrote:

Assuming your tables are set up correctly (that is activities.trip_id
exists) you shouldn’t need anything more than the following in your
controller. That whole second block is redundant.

@trips = Trip.find(:all)

Thank you both for your replies!

Damn!!! I think I’m in love with Rails! I have spent the past 5 hours
trying to get this to work. I had no idea it was that simple. I thought
I had to load the activities separately, then associate them with
their parent trip with this whole multi-dimensional crap as I would have
in PHP.

I feel stupid AND smarter now. Thanks!

5

sorry, but i don’t exactly get your problem…

<% for trip in @trips %>

<%= trip.name%>    

<%= trip.summary%>

    <% for activity in trip.activities %>
  • <%= activity.name %>
    <%= @activity.description %>
    • <% end %>
<% end %>

this looks good so far, but for a small typo in
<%= @activity.description %>
which should be:
<%= activity.description %>

@trips = Trip.find(:all)
ok and all you need

@trips.each do |trip|
a = Activity.find_all_by_trip_id(trip.id)
a.each { |b| c = b.trip_id }
trip.activities = a if trip.id == c
end

don’t know, what you try to do here?

in your Trip model you have defined:
has_many :activities

in Activities model:
belongs_to :trip

then

@trips = Trip.find(:all)
is all you need to do and your code will run, activities are loaded when
needed
or do:
@trips = Trip.find(:all, :include => [:activities])
which would give slightly better db perdormance

6

Welcome to Rails! :wink:

You’ve just described us all.

-Danimal

On Apr 23, 1:27 pm, Jed F. [email protected]