July 2009
Intermediate to advanced
464 pages
12h 25m
English
Content preview from Palm webOSBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Chapter 6. Data
Access to local data storage is a signature feature of native application models. Web applications do not have access to local data storage other than browser cookies. Recently, there has been an effort to address these needs, particularly with the proposed HTML 5 APIs for structured client storage.
Palm webOS supports the HTML 5 Database APIs and provides two specific APIs for simple data creation and access:
- Depot
A wrapper on the HTML 5 APIs for simple object storage and retrieval.
- Cookie
A simplified interface to browser cookies, this is a single object store for small amounts of data.
You will have to evaluate your needs to determine which solution is the best.
Cookies are best used for synchronous access to small amounts of data, such as preferences, version numbers, and other state information.
Both HTML 5 databases and Depot are intended to support caches for offline access and to help with performance issues while accessing online data.
Depot is recommended for storing simple objects without a schema design or manual transaction and query handling; otherwise, use an HTML 5 database.
For disconnected applications that require a data store, an HTML 5 database is the best solution.
Whichever solution you select, it is critical that you provide some local caching for offline use, as stale data is better than no data for most applications. Conversely, you should provide a dynamic source for your data, as it’s best to update the source data when the device is connected. ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.