Best way to populate a dropdown sitewide that is

I am using CakePHP 1.3 and a layout which includes a dropdown of organizations a user has access to administer, so I'm trying to populate that dropdown with organizations that contain the userid that is logged in, but I want to populate it before the user sees anything so they can use it in the header. The dropdown needs to appear on every page once logged in. I tried adding the query to pull these organizations in the appcontroller, but userid was not yet available to use in before filter. Where or how should I do this? S开发者_如何学Gohould it be in session or is there a better construct to use? Element?

In my app it's no problem to use the user_id from within the beforeRender (if you are using the Auth-Component).

You can use it with $this->Auth->user('id').

I would do it like this: Check in the AppController if the user is logged in. If he is, pull your wanted information from the database (or whereever you get your information from) and store it in a variable called $dropdown for example.
If the user is not logged in, $dropdown will be false.
You now make this variable available to the view with $this->set(compact('dropdown'))

Now in your layout (this is important to you have it on every page) you can easily do a check if $dropdown is false or not. If not, you can work with your variable and show the user your wanted dropdown.