On Dec 7, 2010, at 11:13 AM, davel...@mac.com wrote: > I've written a few small personal Mac apps and one iOS app and now am > attempting to write my first NSDocument-based Mac application. I would like > the document itself to be a SQLite file (with specific tables for my app - > not a generic SQLite file). I've been reading through the NSDocument > documentation and it appears this can be done, but I'm not 100% certain of > the steps and wanted to make certain I wasn't going down a path I shouldn't > before getting too far into it. Here is what I think I need to do: > > Here's what I think I need to do in my NSDocument subclass. > > When the user chooses a File->New, the method - (id)initWithType:(NSString > *)typeName error:(NSError **)outError is called so in it I would create a > SQLite database file in a temporary location and call setFileURL: to store > the location of that SQLite file (and store a connection to the SQLite > database file). > > In the - (BOOL)writeToURL:(NSURL *)absoluteURL ofType:(NSString *)typeName > error:(NSError **)outError, if the passed absoluteURL matches the return > value of fileURL: I would do something like commit the SQLite transactions. > If the absoluteURL did not match the returned value of fileURL: I need to > copy the current SQLite file to this location. Will this work ok? > > In the - (BOOL)readFromURL:(NSURL *)absoluteURL ofType:(NSString *)typeName > error:(NSError **)outError I would just open the SQLite file and store my > connection to it for use in the other methods for updating the file. > > Am I missing something? Is attempting to use a SQLite file as the document > file a bad idea? > > I'm also considering an iOS application that uses the same SQLite database > files so that's why I'd like to use SQLite on the Mac if possible. I'm also > not ready to tackle using Core Data although that may be the better option if > there are reasons that SQLite doesn't map well to a NSDocument based > application. My other option is to not use the NSDocument architecture, and > just open one file at a time in my GUI but I thought I'd try to learn about > the NSDocument architecture while writing it. > > Thanks, > Dave
Nobody replied, but in case anyone else wants to try this, I think the best solution is to use the special sqlite :memory: database and load and save files between the file and the :memory: database. See <http://www.sqlite.org/backup.html> In my case the sqlite files will never be more than 100KB so storing them in memory is a reasonable solution. Obviously if your files are much closer to the amount of RAM, this wouldn't be a good solution. If I run into issues farther along in the process with this approach, I'll post a follow-up to this thread, but as of now, I don't see any reason why it won't work. Dave _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
