Rails 3: Using a link_to :action on an "index", isn't working

edit: The bug is that the feed_preference is always nil even after the link_to is pressed, so the (if feed_preference == nil) is always true. I still don't know what's causing this.

What this link_to is supposed to do:

When you press the link, it sorts the post index a certain way. One button sorts by trending value, another sorts by time, etc.

for some reason, in the function "make_feed_preference", the @user.feed_preference NEVER changes, even if i hard code it to @user.feed_preference =开发者_运维问答 "foobar"

but it looks like redirect_to 'posts' is working fine.

    <%= link_to displayIcon(1), {:action => :make_feed_preference, :id => current_user.id,
   :preference => "trending value",  :controller => "users"}, :method=>:post %>

in the users controller:

  def make_feed_preference
   @user = User.find(params[:id])
  @user.feed_preference = params[:preference]

  @user.save

  redirect_to '/posts'
 end

in the view for the posts index:

def index
 @user = current_user

if @user.feed_preference == nil
  @user.feed_preference = "trending value"
end

@posts = Post

unless @user.tag_list == []
  @posts = Post.tagged_with(@user.tag_list, :match_all => :true)
end

if @user.feed_preference == "trending value"
@posts = @posts.order('trending_value DESC').page(params[:page]).per(5)

elsif @user.feed_preference == "time" 
@posts = @posts.order('created_at DESC').page(params[:page]).per(5)

respond_to do |format|
  format.html # index.html.erb
  format.xml  { render :xml => @posts }
end
end

Routes.rb

resources :users do
    resources :comments
    resources :posts
member do 
  get :following, :followers
end 

collection do
  post "tag_with"
  post "clear_tag_list_and_preferences"
  post "make_feed_preference"    
end

end

Whenever I check the values, it's as if clicking the link_to does nothing.

You say it does nothing? The form doesn't even post?

If it's not posting at all... do you have your link_to in a form? If you are using the post method you have to have it in a form unless you are using something like the ujs jQuery libraries which use jQuery / Javascript to help with your 'post' operation.

Using the gem : gem 'jquery-rails' https://github.com/indirect/jquery-rails

I would also like to see your 'rake routes'