Palm OS Web Application Developer's Guide: Developing and Delivering PQAs with Web Clipping
Teach yourself how to develop wireless Web applications for the Palm.
TABLE OF CONTENTS Palm OS Web Application Developer's Guide: Developing and Delivering PQAs with Web Clipping
Optimizing Transport
After you have decided what needs to be sent across the connection, you have to decide how to do it you need a data and transport format that will be easy for the client to recognize and that will save you valuable bandwidth. Although a decision to choose one option will also influence the other, for the sake of discussion, let s split the issue.
Data Format
What should your server-side application generate? HTML? XML? Proprietary format? It mainly depends on what you are willing to do on the client. HTML is not an appropriate format unless you are writing a browser.
Proprietary Format
Most applications would use either this or XML format (explained in the following section). The format is flexible; you send exactly what your client expects. Your data can be 8-bit values. Our example, the Unwired Widgets Mail Reader, uses a proprietary format for its over-the-air protocol.
XML
If you ever had to write a simple C structure to a file, you could simply copy the bytes from memory directly to the file. The version of the structure in the file is a direct image of the memory used by the structure. This fails when storing a linked list of such structures in memory, because a linked list will be spread out everywhere in the memory, and you would not be able to find an easy way to dump it to a file. Just directly dumping each structure would not work because the pointers embedded in the...
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