Hi Jeffrey,

You shouldn't attempt to send UI components from one app to another; you just 
need to send enough info to the peer for it to simulate the same behaviors as 
you're doing locally. There's no out-of-the-box support for synchronizing the 
UI of your Flex app across peers.

Try sending identifiers for the component you're dragging, as well as for the 
drop target. In your messageHandler() method in the receiving app, use these 
identifiers to get references to the local UI components that match, and 
reparent the 'dragged' component under the local 'drop target' component. The 
reparenting could be simple and direct, and you could try to animate it once 
you get the basic scenario working if you wanted (you know where the 'dragged' 
component starts and where it ends up so maybe you could do a straight line 
animation to simulate the original drag and drop). Sorry, don't have time to 
code up anything at the moment.

Seth

From: flexcoders@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Jeffrey 
Walker
Sent: Thursday, May 15, 2008 3:33 PM
To: flexcoders@yahoogroups.com
Subject: Re: [flexcoders] Flex Messaging Service + Drag and Drop List Component

Thanks Seth, this helps a lot. But I am unclear on exactly what should be sent 
to the server inside of AsyncMessage. Below I have my drop handler and message 
handler. I am very new to Flex and I do not understand what to do in the 
message handler (i.e., where to set the received data) so that the consumers 
can actually see the drag an drop action happening. What do you mean by animate 
the item dragged along the simple path? I am using the built in drag and drop 
capabilities of ther List component. Can you please help me with my code? Thanks

private function dragDropHandler(event:DragEvent):void 
            {
                
                // Get the drop target component 
                var dropTarget:List = event.currentTarget as List;

               //Get dragged item 
               var draggedItem:CustomImageRenderer = event.draggedItem as 
CustomImageRenderer;

               //Send the message to the server 
              message = new AsyncMessage();
              message.headers.dropTarget = dropTarget;
              message.headers.draggedItem = draggedItem;
              producer.send(message);
                
            }

            private function messageHandler(event:MessageEvent):void
            {
                //WHAT DO I DO HERE?
                
            }

-- Jeffrey
On Thu, May 15, 2008 at 3:14 PM, Seth Hodgson <[EMAIL PROTECTED]> wrote:
You can put anything you like into the body, or headers, of an AsyncMessage; a 
string, a number, an anonymous Object, a typed Object (if you use a typed 
Object be sure to tag it with [RemoteClass] metadata). You can control which 
subscribed Consumers receive the message by using the Consumer.selector 
property (a SQL-92 expression evaluated on the server against the headers of 
incoming messages; if the message headers satisfy the expression the message 
will be delivered to the Consumer), or by using the Consumer.subtopic property 
to subscribe to a subtopic (or range of subtopics) within a destination and 
using the Producer.subtopic property to control which specific subtopic sent 
messages go to.

When building 'screen-sharing' style applications like this, you need to really 
keep network latency in mind. Some GUI frameworks will 'summarize' events 
before handing off to even local processing (i.e. collapsing a bunch of 
individual key strokes into a summary string containing all the characters 
typed since the last event dispatch and just dispatching that single event). 
This becomes even more important when you're considering sending lots of high 
frequency events over the network to peers.

In this case, I'd recommend sending a single message to subscribed peers on 
drop complete, indicating which component was dragged and dropped along with 
its final location. You can then either just reparent the corresponding 
component immediately on the receiving peer, or animate it along a simple path. 
There are lots of options with this sort of thing, but you shouldn't try to 
generate and send a message for each pixel it is dragged.

Hope that helps,
Seth

From: flexcoders@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of 
jeffreyr6915
Sent: Wednesday, May 14, 2008 11:01 PM
To: flexcoders@yahoogroups.com
Subject: [flexcoders] Flex Messaging Service + Drag and Drop List Component


I have a 2 list components in which I have enabled drag and drop
(dragEnabled="true" dropEnabled="true" dragMoveEnabled="true"
dragDrop="dragDropHandler(event)"). So, I am able to drag and drop the
List items (which I have a custom itemRenderer for). I am also using
flex messaging service (Flex data services) so that a change made in
one connected client/browser is propagated to all other connected
browsers. I would like to be able to drag an item from one list to
another (in one browser) and see that drag and drop happen (as it is
happening) in all other connected browsers. I know that I need to send
an AsyncMessage to the server via a producer, and receive from the
server via a consumer.

Question: What do I include in the async message in order to see the
list items drag/drop as it is happening in all connected browsers? 

Can someone help me with code/example? Thanks

 

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