NSObject+NSCoding and Archiver
------------------------------
Mike Mayo
Rackspace Mobile Apps
mike@overhrd.com
twitter: @greenisus
These are some simple classes to make object persistence with NSCoding easier. This code was extracted from
the Rackspace Cloud / OpenStack iOS app at http://launchpad.net/openstack-ios
INSTALLATION
To install, simply drag Archiver.h, Archiver.m, NSObject+NSCoding.h, and NSObject+NSCoding.m into your project.
Then, right click Frameworks in Groups & Files and choose Add -> Existing Frameworks... and choose libobjc.A.dylib.
USAGE
-- Archiver
This class will read and write objects that conform to the NSCoding protocol to disk.
Archiver Usage:
SomeClass *myObject = [[[SomeClass alloc] init] autorelease];
myObject.someProperty = @"Hello world";
[Archiver persist:myObject key:@"myObject"];
// later on somewhere else...
SomeClass *myObject = [Archiver retrieve:@"myObject"];
-- NSObject+NSCoding
This category simplifies implementing NSCoding by iterating over the properties of your
class and encoding/decoding them for you. It persists primitives (such as ints and floats)
as well as any objects that conform to NSCoding.
NSObject+NSCoding Usage:
In your class header, conform to NSCoding:
@interface Model : NSObject <NSCoding> {
//...
}
In your class implementation, call the automatic methods:
- (void)encodeWithCoder:(NSCoder *)coder {
[self autoEncodeWithCoder:coder];
}
- (id)initWithCoder:(NSCoder *)coder {
if (self = [super init]) {
[self autoDecode:coder];
}
return self;
}