TechNote (Archived)

Using the NetConnection Debugger in Flex

To assist with AMF debugging during development, you can use the NetConnection Debugger that is provided with Macromedia Flex.

Within the {flex_install_dir}/extras/netConnectionDebugger directory, you will find the netConnectionDebugger.html and netConnectionDebugger.swf files that can help you sniff out and debugAMF issues with Flex. When<mx:RemoteObject> is used in Flex, the default protocol is AMF. Flex ships with its own AMF gateway but you also have the option of connecting to other Flash Remoting gateways. You can use the gateway that is provided with ColdFusion, JRun, J2EE version or the .NET gateway. Without adequate debugging information, it can be difficult to troubleshoot issues with<mx:RemoteObject>.

The steps for using the NetConnection Debugger are outlined below.

Open the /flex_app_root/WEB-INF/flex/flex-config.xml file for editing.
Locate the <debugging>...</debugging> section and find the following entry:
```
 <remote-objects-debug>false</remote-objects-debug> 
```

Set the value to true.

For example:

 <remote-objects-debug>true</remote-objects-debug>

Restart the server for the changes to take effect.
Open a browser and enter the URL to the netConnectionDebugger.html file.

For example, on Windows, use the following:

C:\Program Files\Macromedia\Flex\extras\netConnectionDebugger\NetConnectionDebugger.html
Now you are ready to start debugging. Open another browser window and enter the URL of the MXML page that uses AMF (for example, http://localhost:8080/flexSamples/explorer/data/RemoteObjectAMFDemo.mxml). The AMF client server interaction will be shown in the NetConnection Debugger, as illustrated in the example below.

Note: You do not need the Flash debug player for this to work since the NetConnection Debugger works similar to a sniffer.

Troubleshooting:

If the output doesn't appear, first verify that you modified the flex-config.xml as shown in the steps above. Then, try refreshing the MXML page a few times to make sure it is recompiled. If the output still does not appear, you may need to modify the file and save it again to force the compile process.