Flex 3 Solutions excerpt from my book on Adobe Flex Developer Center

Recently Adobe has published on the Flex Developer Center some articles taken from my Flex 3 book, Flex Solutions: Essential Techniques for Flex 2 and 3 Developers.
Enjoy them form free ;)

Flex Solutions excerpt: Uploading files to the server
Uploading and downloading files from the client to the server are operations that are often indispensable in an application. Uploading files that reside on the client's computer is a feature on which many web applications have founded their success. Would YouTube or Flickr (two of the most well-known web applications) be as successful if they did not offer the possibility of uploading files from the user's computer to the web server?

Working with remote data using the RPC classes
Up to this point in the book, you have familiarized yourself with the basic methods of Flex: you learned how to use some of the elements that allow you to define the user interface of an application, how to load external data using data models, and how to convert these data models into collection classes.

Migrating Flex applications onto the desktop with Adobe AIR
One of the characteristics of rich Internet applications (RIAs) developed with Flex is that they actually act as client-side applications. In fact, an RIA, after having been requested by users by launching the URL on a common browser, is downloaded onto the client and resides on the client for its entire life cycle. The interfaces created for RIAs are very rich and user-friendly, and many of the operations you use for desktop applications can also be developed for this type of application. For example, in Solutions 7-6 and 7-7, you saw that the classic operations of drag and drop are simple and quick to manage. The difference between a client-side application and a desktop application is small. The main reason why an RIA cannot be considered a desktop application is that it is loaded and run within the Flash Player that is a plug-in of the browser. This difference prevents the developer from using some of the functions that are native to desktop applications and very useful for most projects. The access to the file system to load, save, and edit local files, and the possibility of changing the appearance of the windows of the operating system are impossible because of the nature of RIAs.

Comments

[John Mayo]

I have an assignment to develop delete and update functions to XML data imported externally. I cannot find any reference material for this. Assuming the XML has been imported into a DataGrid, do you have suggestions as to how we modify or delete objects in the XML file and update it?