Rails AJAX question

ruby-talk
1

Hi all, It must be a very simple solution, but i'm just not getting it.
I want to display some picture continously on a page using Rail+AJAX.
Here is the snippet of code:

Controller

···

------------------------
def show
    @albums = Album.find(:all)
    @size = @albums.length
  end

def show_next
    @id = params[:cur_id].to_i
    @size = params[:max].to_i
    if ( @id == 0 or ir @id > @size)
      @id = 1
    end

    @album = Album.find(@id)
    @id += 1
end

show.rhtml
-------------------------------------
<html>
<body>
       Continous picture display<br>
   <%= periodically_call_remote(:update => 'mydiv',
                             :url => { :action => :show_next,
:cur_id => @id, :max => @size},
                             :frequency => 2 )
   <div id="mydiv">
     image will display here
   </div>
</body>
</html>

show_next.rhtml
-------------------------------------

def show_next
  <img width="600" height="200" src="<%= @album .image_url %>"/>
end

------------------------------------------------------------------------------------------------------------------

But the @id is not being updated. I think I need to store the @id
statically in the html page (may as hidden field), but is there any
better solution for this

thanks in avdvance
/Rick

2

EWRONGMAILINGLIST

http://lists.rubyonrails.org/mailman/listinfo/rails

Tsume

···

On Friday 10 February 2006 01:53 pm, voice10@gmail.com wrote:

Hi all, It must be a very simple solution, but i'm just not getting it.
I want to display some picture continously on a page using Rail+AJAX.
Here is the snippet of code:

Controller
------------------------
def show
    @albums = Album.find(:all)
    @size = @albums.length
  end

def show_next
    @id = params[:cur_id].to_i
    @size = params[:max].to_i
    if ( @id == 0 or ir @id > @size)
      @id = 1
    end

    @album = Album.find(@id)
    @id += 1
end

show.rhtml
-------------------------------------
<html>
<body>
       Continous picture display<br>
   <%= periodically_call_remote(:update => 'mydiv',

                             :url => { :action => :show_next,
:
:cur_id => @id, :max => @size},
:
                             :frequency => 2 )

   <div id="mydiv">
     image will display here
   </div>
</body>
</html>

show_next.rhtml
-------------------------------------

def show_next
  <img width="600" height="200" src="<%= @album .image_url %>"/>
end

---------------------------------------------------------------------------
---------------------------------------

But the @id is not being updated. I think I need to store the @id
statically in the html page (may as hidden field), but is there any
better solution for this

thanks in avdvance
/Rick

3

I liked this tutorial, it has a nice example on the lack of memory of
web applications
http://www.troubleshooters.com/codecorn/ruby/rails/rapidlearning_rails.htm

I have been working with a controller code as such
   if params.has_key? :id
         @laststimobj=Stimuli.find(params[:id])
         @stimuliobj=Stimuli.find(params[:id].to_i + 1)
     else
         @stimuliobj = Stimuli.find(:first)
     end

with a form in the view
<%= start_form_tag(:action => "hello") %>
  <%= hidden_field_tag "id", @stimuliobj.id %>
  <p>
      Name:
    <%= text_field("responseobj", "name", "size" => "20") %>
    <%= submit_tag("Name") %>
    <% end_form_tag %>

you can use
render_text params.inspect
in your show_next method to see what your parameter hash is like. I am
not sure if an action redirect can transmit parameters.