I'm building an app that fetches XML from a server, then parses it (it's DIDL formatted in places). The goal is to load as much into memory as possible to make it easier for users to browse (so as to enable fast scrolling through results), but I keep getting OutOfMemoryErrors. I'm kind of new to Android, and it seems like the VMs are really finicky about things. I'm loading no more than a megabyte of XML, and pretty much discarding it right away. What should I do to prevent these errors from happening?
Should I load chunk by chunk of the file over the network, write it to disk, then load chunk by chunk back into and out of memory, parsing everything into POJOs? If it can be avoided, I'd like to not have to implement some form of pagination, as per the Twitter app (it used to load more entries when you hit the bottom, it now loads a lot all at once and likewise crashes with an OOM error.) I'm running a Nexus One if that helps, CM7/Android 2.3.3.
You can read this nice article about XML parsing on Android. Using pull parser would be good choice for you, since it does not need to read complete document into the memory, which is the problem in your case. I would suggest that you store parsed results into the database, since once they are there, you can quickly do list them and page them any way you want, and performance of the DB is great. This way, you need to do loading of complete data from server to DB just once (if data is not changing on the server) or to load it once and then to get updates from time to time if it is changing (like in case of twitter).