Graphics Programs Reference
In-Depth Information
@class RSSItem;
@interface BNRFeedStore : NSObject
{
NSManagedObjectContext *context;
NSManagedObjectModel *model;
}
+ (BNRFeedStore *)sharedStore;
@property (nonatomic, strong) NSDate *topSongsCacheDate;
- (void)fetchTopSongs:(int)count
withCompletion:(void (^)(RSSChannel *obj, NSError *err))block;
- (RSSChannel *)fetchRSSFeedWithCompletion:
(void (^)(RSSChannel *obj, NSError *err))block;
- (void)markItemAsRead:(RSSItem *)item;
- (BOOL)hasItemBeenRead:(RSSItem *)item;
@end
Before moving on with the implementation, let's see how it is going to work. Currently,
when the user taps on a row that corresponds to an
RSSItem
, the
ListViewControl-
ler
loads that
RSSItem
into the
WebViewController
to display it. Now, the
ListViewController
will also send the message
markItemAsRead:
to the
BNRFeedStore
with the selected
RSSItem
. The store will grab the
link
from the
RSSItem
and insert it into Core Data.
Also, each time the
ListViewController
reloads its table, it will ask the store, “Has
this item been marked as read?” The store will check with Core Data, and the
ListViewController
will place a checkmark in the row if the corresponding item
has been read.
In
BNRFeedStore.m
, add an
init
method to create the appropriate objects for Core
Data to work.
- (id)init
{
self = [super init];
if (self) {
model = [NSManagedObjectModel mergedModelFromBundles:nil];
NSPersistentStoreCoordinator *psc =
[[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:model];
NSError *error = nil;
NSString *dbPath =
[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,
NSUserDomainMask,
YES) objectAtIndex:0];
dbPath = [dbPath stringByAppendingPathComponent:@"feed.db"];
NSURL *dbURL = [NSURL fileURLWithPath:dbPath];
if (