Sending POST data to another window

[OneSeventeen]

Right now I'm doing the following to post to a shopping cart for paypal:

PHP Code:

p= new LoadVars();
p.cmd="_cart";
p.business="[email protected]";
p.item_name="T-Shirt";
p.item_number=sid+_root.size+_root.current_color;
p.amount=_root.theprice;
var add_var="add";
p[add_var]=1
p.send("https://www.paypal.com/cgi-bin/webscr", "paypal", POST); 


and the way it works is paypal wants their window to stay open all the time, because every time I add something to the cart and click "continue shopping" it simply sets the focus to the parent page.
I figured the send() would send the post data to the "paypal" window, as specified in the function arguments, but instead it appears as though it tests to see if the window is open, and if it is, it doesn't do anything....
If I close the paypal window and use the flash function to add another item it works perfectly, but not everyone going to the site knows this.

Is there anyway to have 2 windows open and have the flash window post into another window?

Window "foo":
[flash animation with 'add to cart' button submitting to "bar"]

Window "bar":
[paypal site waiting to receive more items to be purchased by "foo"]

You can see an example at http://www.wumk.com/shirt/9760002/xxl
(Disclaimer: I don't personally care for the site and wouldn't go there if you are easily offended like I am)

Just try to add the same item to your cart two or three times without closing the paypal window, if you can.

[Slowburn]

instead of doing it this way, could you not just have the person add the items to the cart without leaving Flash...then once the user is done "shopping" they could hit a button to checkout. this would forward all the items they have bought to that window. This way, the user won't have many wiondows open at one time. I know that is annoying for me.

[CyanBlue]

What Slowburn said is pretty much how those PayPal components are handling the job... You take care of all the transaction until the user checks out the cart and send out the all the information to PayPal to process...

[Slowburn]

Cheers for making that more clear. :P

[petefs]

I agree with cyanblue/slowburn.

For posterity, though, I came across this when developing a content server that uses multiple windows with localconnections to communicate. The concept is that only one of the three windows needs to be open for the application to continue working. 1) content browser, 2) playlist, 3) player/display. To detect when windows were opened or closed and whether or not to focus them or reposition them I found that using fscommand was my best bet. All window opening/closeing is handled by js commands initiated by flash. If their suggestions just don't do it for ya, that's your best bet ^_^

[OneSeventeen]

I think I might look into this fscommand thing, because the only problem I'm having with the external window is that the user will use the flash animation to determine the color of their shirt, add it to the cart, then they may want to go to the home page again and select another slogan, choose another shirt, and add that item to the cart as well, so they won't be staying on the same flash script the whole time.
I'm looking into having PHP add the items to the cart, and let flash say "added to cart" or something, then fade it out, if the item was successfully added. Then PHP would be doing all the cart work, and hopefully wouldn't need to open up a new window.

I just really don't want to develop a new shopping cart when I can just use paypal's.