[Rails-spinoffs] Re: Update Cart after download

[Colin Mollenhour]

Why store the cart on the server? why not locally? Maybe some sort of iframe hack would let you download the file and attach an event on completion but I'd think that clearing the cart when they click the download link would be good enough. Only disadvantage would be if they clicked cancel they'd have to refill the cart to try again, but you can only account for so much carelessness on behalf of the user :)  See http://ecosmear.com/relay/ Colin Walter Lee Davis wrote: The cart loads at page load and then is continuously updated without screen refresh. It is backed by the database, and that database is read by download.php to get its list of files to download. If download is successful in contacting the secure WEBDAV repository with all the big files in it (the database is just a proxy), downloading the actual files and mashing them into a zip -- then it clears the cart. But since I am just linking to (what appears to the browser as) a plain zip file for download, and that zip file doesn't exist until the download script has finished its business, I don't see how I can tell the cart to update on screen after the download has finished. It's tricky. Walter On Mar 19, 2007, at 5:14 PM, Gareth Evans wrote: On your download link, apply an onclick handler as well as a href- the onclick can clear your on-screen shopping cart. When is the on-screen list being loaded? at page load, ie: the rest of the site isn't ajax based? Or does the cart remain onscreen at all times with no refresh.   <a href="" > (inline handlers are bad) This will cause the cart to clear, then the user will navigate to downloadlink.php. If you didn't want them to download, you could return false. If you attach the event with Event.Observe you have to use Event.Stop(e) though   Hope this helps   Gareth   On 3/20/07, Walter Lee Davis <[EMAIL PROTECTED]> wrote: I have a shopping cart on a page that gathers files for download. As the user browses around the various nested folders, she can add things to the cart, remove single items from the cart, and empty the entire cart. At any time, she can also download the entire cart contents as a Zip archive. I am managing that download using a PHP script that forces the file-type, and thus all I do is link to a real file (download.php?cart=N) from my page. The last step of the download script is to empty out the cart in the database. But the list on screen remains the same until the visitor navigates to another folder, at which point it refreshes and declares itself empty. Which is kind of jarring to the user. I tried applying a periodic updater to the cart div, and that did work, but it also killed the other events I had registered inside that div (the individual files' remove me buttons). It also issued a request every five seconds, which seems extreme. I am experimenting with just setting a delay after the click and checking the cart again, but that seems fragile, since I don't know how long it might take for the server to respond with the files. If I check before it's done, the cart will be the same (since the download hasn't started yet and the script returned true) and if I wait too long, it will be jarring for the user. Any suggestions? I can't show any code, it's all hidden inside an HTTPS site. I could do some extractions, I guess, but I am hoping someone may have done this before and have a bright idea or two. Thanks, Walter > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Spinoffs" group. To post to this group, send email to rubyonrails-spinoffs@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/rubyonrails-spinoffs?hl=en -~----------~----~----~----~------~----~------~--~---