About debugging data binding and web services (Flash Professional only)

Data binding is a series of actions that take place in response to events, such as the following:

• The data of a component property changes.
• A web service call is completed.
• An XML document is fetched.

All actions that are performed by data binding or web services are reported to a log, which you can control by turning the trace log on:

_global.__dataLogger=new mx.data.binding.Log();  //to enable trace log

Or you can turn the trace log off:

_global.__dataLogger=null; //disable trace for binding.

When you run an application that turns the trace on, a detailed log of data binding and web services events and actions appears in the Output window. The following are the types of things reported:

• Executing bindings
• Calling web service methods
• Fetching XML documents
• Status and result events from WebService and XML components
• Valid and invalid events from validated data fields
• A variety of errors, invalid settings, and so on that are checked for

By running your application and then examining the log, you can often find out why things are not working as expected. Sometimes an error is explicitly reported—for example, a missing web service parameter. Sometimes the data is bound to the wrong component, or to no component, and so on. If you find that there is too much information in the log, clear the Output window by selecting Clear from the context menu, to keep the log as short as possible.