1.首先创建父类吧重用的代码写在里边

#import <Foundation/Foundation.h>
#import <CoreData/CoreData.h> @interface DBCenter : NSObject @property (nonatomic, strong) NSManagedObjectContext *managedObjectContext;
@property (nonatomic, strong) NSManagedObjectModel *managedObjectModel;
@property (nonatomic, strong) NSPersistentStoreCoordinator *persistentStoreCoordinator; - (NSURL *) modelURL; //need to be overwrite
- (NSURL *) storeURL; //need to be overwrite
- (NSString *) storeDirectoryPath;
- (NSString *) entityName;
- (void) saveContext; @end
#import "DBCenter.h"

@interface DBCenter ()

@end

@implementation DBCenter

- (NSManagedObjectModel *)managedObjectModel {
// The managed object model for the application. It is a fatal error for the application not to be able to find and load its model.
if (_managedObjectModel != nil) {
return _managedObjectModel;
} // NSBundle *bundle = [NSBundle bundleWithURL:[[NSBundle mainBundle] URLForResource:@"Resources" withExtension:@"bundle"]];
// NSURL *modelURL = [bundle URLForResource:@"LECPlayerDataModel" withExtension:@"momd"];
NSURL *modelURL = [self modelURL]; _managedObjectModel = [[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL];
return _managedObjectModel;
} - (NSPersistentStoreCoordinator *)persistentStoreCoordinator {
// The persistent store coordinator for the application. This implementation creates and return a coordinator, having added the store for the application to it.
if (_persistentStoreCoordinator != nil) {
return _persistentStoreCoordinator;
} // Create the coordinator and store _persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:[self managedObjectModel]];
NSURL *storeURL = [self storeURL]; NSError *error = nil;
NSString *failureReason = @"There was an error creating or loading the application's saved data.";
if (![_persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:storeURL options:nil error:&error]) {
// Report any error we got.
NSMutableDictionary *dict = [NSMutableDictionary dictionary];
dict[NSLocalizedDescriptionKey] = @"Failed to initialize the application's saved data";
dict[NSLocalizedFailureReasonErrorKey] = failureReason;
dict[NSUnderlyingErrorKey] = error;
error = [NSError errorWithDomain:@"YOUR_ERROR_DOMAIN" code: userInfo:dict];
// Replace this with code to handle the error appropriately.
// abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
abort();
} return _persistentStoreCoordinator;
} - (NSManagedObjectContext *)managedObjectContext {
// Returns the managed object context for the application (which is already bound to the persistent store coordinator for the application.)
if (_managedObjectContext != nil) {
return _managedObjectContext;
} NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator];
if (!coordinator) {
return nil;
}
_managedObjectContext = [[NSManagedObjectContext alloc] init];
[_managedObjectContext setPersistentStoreCoordinator:coordinator];
return _managedObjectContext;
} #pragma mark -
- (NSURL *) modelURL {
return nil;
} - (NSURL *) storeURL {
return nil;
} - (NSString *) storeDirectoryPath {
NSString *documentDirectory = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject];
NSString *dbDirectory = [documentDirectory stringByAppendingPathComponent:@"DB"];
NSFileManager *fileManager = [NSFileManager defaultManager];
if (![fileManager fileExistsAtPath:dbDirectory]) {
[fileManager createDirectoryAtPath:dbDirectory
withIntermediateDirectories:YES
attributes:nil
error:nil];
}
return dbDirectory;
} - (NSString *) entityName {
return nil;
} - (void)saveContext {
NSManagedObjectContext *managedObjectContext = self.managedObjectContext;
if (managedObjectContext != nil) {
NSError *error = nil;
if ([managedObjectContext hasChanges] && ![managedObjectContext save:&error]) {
// Replace this implementation with code to handle the error appropriately.
// abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
abort();
}
}
} @end

2.然后对于某一个存储模块独立出来继承

@interface DBCenterNewsExtend : DBCenter

+ (DBCenterNewsExtend *) sharedNewsDBCenter;

/*启动广告*/
- (LaunchingAdItemModel *) launchingAdItem;
- (void) fullFillLaunchingAdItemModelWithLaunchingAdItem:(LaunchingAdItem *) launchingAdItem;
- (void) saveLaunchingAdItemDataModel;
- (void) removeLaunchingAdItem; /*新闻阅读记录*/
- (BOOL) hasReadWithNewsId:(NSString *) newsId;
- (void) addReadRecordWithNewsId:(NSString *) newsId; /*新闻收藏记录*/
- (BOOL) hasFavoriteWithNewsId:(NSString *) newsId;
- (void) addFavoriteRecordWithNewsDisplayItem:(NewsDisplayItem *) newsDisplayItem;
- (void) removeFavoriteRecordWithNewsId:(NSString *) newsId;
- (NSArray *) favoriteNewsList; //NSArray<NewsParamItem> /*搜索关键字列表*/
- (void) addSearchKeywordRecord:(NSString *) keyword;
- (NSArray *) keywordsList; //NSArray<NewsSearchKeywordModel>
- (void) cleanKeywordsList; @end
@interface DBCenterNewsExtend ()

@property (nonatomic, strong) LaunchingAdItemModel *launchingAdItemModel;
@property (nonatomic, strong) NSMutableArray *mNewsReadRecordsList;
@property (nonatomic, strong) NSMutableArray *mNewsDisplayModelList;
@property (nonatomic, strong) NSMutableArray *mNewsDisplayItemList;
@property (nonatomic, strong) NSMutableArray *mSearchKeywordsList; - (void) loadLaunchingAdItemModel;
- (NSString *) launchingAdEntityName; - (void) loadReadRecordsList;
- (NSString *) newsReadRecordEntityName;
- (NewsReadRecordItemModel *) newsReadRecordItemModelWithNewsId:(NSString *) newsId; - (void) loadFavoriteRecordsList;
- (NSString *) newsDisplayItemEntityName;
- (NewsDisplayItem *) newsDisplayItemFromNewsDisplayDataModel:(NewsDisplayItemDataModel *) newsDisplayItemDataModel;
- (NewsDisplayItemDataModel *) insertNewsDisplayItemDataModelFromNewsDisplayItem:(NewsDisplayItem *) newsDisplayItem;
- (NewsDisplayItem *) newsDisplayItemWithNewsId:(NSString *) newsId;
- (NewsDisplayItemDataModel *) newsDisplayItemDataModelWithNewsId:(NSString *) newsId; - (void) loadSearchKeywordsList;
- (NSString *) searchKeywordEntityName;
- (NewsSearchKeywordModel *) searchDataModelWithKeyword:(NSString *) keyword; @end @implementation DBCenterNewsExtend - (id) init {
if (self = [super init]) {
[self loadLaunchingAdItemModel];
[self loadReadRecordsList];
[self loadFavoriteRecordsList];
[self loadSearchKeywordsList];
}
return self;
} #pragma mark -
#pragma mark Overwrite
- (NSURL *) modelURL {
NSString *modelPath = [[NSBundle mainBundle] pathForResource:@"NewsModel" ofType:@"momd"];
NSURL *modelURL = [NSURL URLWithString:modelPath];
return modelURL;
} - (NSURL *) storeURL {
NSString *directoryPath = [self storeDirectoryPath];
NSString *storePath = [directoryPath stringByAppendingPathComponent:@"NewsModel.sqlite"];
return [NSURL fileURLWithPath:storePath];
} #pragma mark -
#pragma mark Public Methods
+ (DBCenterNewsExtend *) sharedNewsDBCenter {
static DBCenterNewsExtend *newsDBCenter = nil;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
newsDBCenter = [[DBCenterNewsExtend alloc] init];
});
return newsDBCenter;
} - (LaunchingAdItemModel *) launchingAdItem {
return _launchingAdItemModel;
} - (void) fullFillLaunchingAdItemModelWithLaunchingAdItem:(LaunchingAdItem *) launchingAdItem {
if (!_launchingAdItemModel) {
_launchingAdItemModel = [NSEntityDescription insertNewObjectForEntityForName:[self launchingAdEntityName] inManagedObjectContext:self.managedObjectContext];
[self saveContext];
}
_launchingAdItemModel.adId = launchingAdItem.adId;
_launchingAdItemModel.adTitle = launchingAdItem.adTitle;
_launchingAdItemModel.adImgUrl = launchingAdItem.adImgUrl;
_launchingAdItemModel.adWebUrl = launchingAdItem.adWebUrl;
_launchingAdItemModel.adEndTime = launchingAdItem.adEndTime;
[self saveContext];
} - (void) saveLaunchingAdItemDataModel {
[self saveContext];
} - (void) removeLaunchingAdItem {
[[self managedObjectContext] deleteObject:_launchingAdItemModel];
_launchingAdItemModel = nil;
} - (BOOL) hasReadWithNewsId:(NSString *) newsId {
bool hasRead = NO;
if ([self newsReadRecordItemModelWithNewsId:newsId]) {
hasRead = YES;
}
return hasRead;
} - (void) addReadRecordWithNewsId:(NSString *) newsId {
if (![self newsReadRecordItemModelWithNewsId:newsId]) { NewsReadRecordItemModel *newsReadRecordItemModel = [NSEntityDescription insertNewObjectForEntityForName:[self newsReadRecordEntityName] inManagedObjectContext:self.managedObjectContext];
newsReadRecordItemModel.newsId = newsId;
[_mNewsReadRecordsList addObject:newsReadRecordItemModel];
[self saveContext];
}
} /*新闻收藏记录*/
- (BOOL) hasFavoriteWithNewsId:(NSString *) newsId {
for (NewsDisplayItem *newsDisplayItem in _mNewsDisplayItemList) {
if (newsDisplayItem.newsDisplayParamItemList.count > ) {
NewsDisplayParamItem *displayParamItem = newsDisplayItem.newsDisplayParamItemList[];
if ([displayParamItem.newsId isEqualToString:newsId]) {
return YES;
}
}
}
return NO;
} - (void) addFavoriteRecordWithNewsDisplayItem:(NewsDisplayItem *) newsDisplayItem {
NewsDisplayParamItem *newsDisplayParamItem;
if (newsDisplayItem.newsDisplayParamItemList.count > ) {
newsDisplayParamItem = newsDisplayItem.newsDisplayParamItemList[];
}
NSString *newsId = newsDisplayParamItem.newsId;
if (![self hasFavoriteWithNewsId:newsId]) {
[self insertNewsDisplayItemDataModelFromNewsDisplayItem:newsDisplayItem];
}
} - (void) removeFavoriteRecordWithNewsId:(NSString *) newsId {
NewsDisplayItemDataModel *newsDisplayItemDataModel = [self newsDisplayItemDataModelWithNewsId:newsId];
if (newsDisplayItemDataModel) {
[[self managedObjectContext] deleteObject:newsDisplayItemDataModel];
[self saveContext];
} NewsDisplayItem *newsDisplayItem = [self newsDisplayItemWithNewsId:newsId];
if (newsDisplayItem) {
[_mNewsDisplayItemList removeObject:newsDisplayItem];
}
} - (NSArray *) favoriteNewsList {
return _mNewsDisplayItemList;
} /*搜索关键字列表*/
- (void) addSearchKeywordRecord:(NSString *) keyword {
if (![self searchDataModelWithKeyword:keyword]) {
NewsSearchKeywordModel *newsSearchKeywordModel = [NSEntityDescription insertNewObjectForEntityForName:[self searchKeywordEntityName] inManagedObjectContext:self.managedObjectContext];
newsSearchKeywordModel.keyword = keyword;
[_mSearchKeywordsList addObject:newsSearchKeywordModel];
[self saveContext];
}
} - (NSArray *) keywordsList {
NSMutableArray *mKeywordList = [[NSMutableArray alloc] init];
for (NewsSearchKeywordModel *keywordModel in _mSearchKeywordsList) {
[mKeywordList addObject:keywordModel.keyword];
}
return mKeywordList;
} - (void) cleanKeywordsList {
for (NewsSearchKeywordModel *searchKeywordModel in _mSearchKeywordsList) {
[[self managedObjectContext] deleteObject:searchKeywordModel];
}
[_mSearchKeywordsList removeAllObjects];
[self saveContext];
} #pragma mark -
#pragma mark Public Methods
- (void) loadLaunchingAdItemModel {
NSFetchRequest* request=[[NSFetchRequest alloc] init];
NSEntityDescription* userItemDataModelDescription = [NSEntityDescription entityForName:[self launchingAdEntityName] inManagedObjectContext:self.managedObjectContext];
[request setEntity:userItemDataModelDescription];
NSArray* fetchResultList = [self.managedObjectContext executeFetchRequest:request error:nil];
if (fetchResultList.count > ) {
_launchingAdItemModel = fetchResultList[];
}
} - (NSString *) launchingAdEntityName {
return @"LaunchingAdItemModel";
} - (void) loadReadRecordsList {
NSFetchRequest* request=[[NSFetchRequest alloc] init];
NSEntityDescription* userItemDataModelDescription = [NSEntityDescription entityForName:[self newsReadRecordEntityName] inManagedObjectContext:self.managedObjectContext];
[request setEntity:userItemDataModelDescription];
NSArray* fetchResultList = [self.managedObjectContext executeFetchRequest:request error:nil];
_mNewsReadRecordsList = [NSMutableArray arrayWithArray:fetchResultList];
} - (NSString *) newsReadRecordEntityName {
return @"NewsReadRecordItemModel";
} - (NewsReadRecordItemModel *) newsReadRecordItemModelWithNewsId:(NSString *) newsId {
for (NewsReadRecordItemModel *newsReadRecordItemModel in _mNewsReadRecordsList) {
if ([newsReadRecordItemModel.newsId isEqualToString:newsId]) {
return newsReadRecordItemModel;
}
}
return nil;
} - (void) loadFavoriteRecordsList {
_mNewsDisplayModelList = [[NSMutableArray alloc] init];
_mNewsDisplayItemList = [[NSMutableArray alloc] init]; NSFetchRequest* request=[[NSFetchRequest alloc] init];
NSEntityDescription* userItemDataModelDescription = [NSEntityDescription entityForName:[self newsDisplayItemEntityName] inManagedObjectContext:self.managedObjectContext];
[request setEntity:userItemDataModelDescription];
NSArray* fetchResultList = [self.managedObjectContext executeFetchRequest:request error:nil];
_mNewsDisplayModelList = [NSMutableArray arrayWithArray:fetchResultList]; for (NewsDisplayItemDataModel *newsDisplayItemDataModel in _mNewsDisplayModelList) {
NewsDisplayItem *newsDisplayItem = [self newsDisplayItemFromNewsDisplayDataModel:newsDisplayItemDataModel];
[_mNewsDisplayItemList addObject:newsDisplayItem];
}
} - (NSString *) newsDisplayItemEntityName {
return @"NewsDisplayItemDataModel";
} - (NewsDisplayItem *) newsDisplayItemFromNewsDisplayDataModel:(NewsDisplayItemDataModel *) newsDisplayItemDataModel {
NewsDisplayItem *newsDisplayItem = [[NewsDisplayItem alloc] init];
newsDisplayItem.displayType = [newsDisplayItemDataModel.displayType integerValue];
newsDisplayItem.subscriptType = [newsDisplayItemDataModel.subscriptType integerValue]; NewsDisplayParamItem *newsDisplayParamItem = [[NewsDisplayParamItem alloc] init];
newsDisplayParamItem.newsId = newsDisplayItemDataModel.newsId;
newsDisplayParamItem.newsTitle = newsDisplayItemDataModel.newsTitle;
newsDisplayParamItem.newsBrief = newsDisplayItemDataModel.newsBrief;
newsDisplayParamItem.newsDetailType = [newsDisplayItemDataModel.newsDetailType integerValue];
newsDisplayParamItem.imagesList = [newsDisplayItemDataModel.newsImageList componentsSeparatedByString:@" "]; newsDisplayItem.newsDisplayParamItemList = @[newsDisplayParamItem]; return newsDisplayItem;
} - (NewsDisplayItemDataModel *) insertNewsDisplayItemDataModelFromNewsDisplayItem:(NewsDisplayItem *) newsDisplayItem {
NewsDisplayItemDataModel *newsDisplayItemDataModel = [NSEntityDescription insertNewObjectForEntityForName:[self newsDisplayItemEntityName] inManagedObjectContext:self.managedObjectContext];
newsDisplayItemDataModel.displayType = @(newsDisplayItem.displayType);
newsDisplayItemDataModel.subscriptType = @(newsDisplayItem.subscriptType); if (newsDisplayItem.newsDisplayParamItemList.count > ) {
NewsDisplayParamItem *newsDisplayParamItem = newsDisplayItem.newsDisplayParamItemList[]; newsDisplayItemDataModel.newsId = newsDisplayParamItem.newsId;
newsDisplayItemDataModel.newsBrief = newsDisplayParamItem.newsBrief;
newsDisplayItemDataModel.newsDetailType = @(newsDisplayParamItem.newsDetailType);
newsDisplayItemDataModel.newsTitle = newsDisplayParamItem.newsTitle; NSMutableString *newsImageListString = [[NSMutableString alloc] init];
for (int i = ; i < newsDisplayParamItem.imagesList.count; i++) {
NSString *imageUrl = newsDisplayParamItem.imagesList[i];
[newsImageListString appendString:imageUrl];
if (i < newsDisplayParamItem.imagesList.count - ) {
[newsImageListString appendString:@" "];
}
}
newsDisplayItemDataModel.newsImageList = newsImageListString;
} [_mNewsDisplayModelList addObject:newsDisplayItemDataModel];
[_mNewsDisplayItemList addObject:newsDisplayItem]; [self saveContext]; return newsDisplayItemDataModel;
} - (NewsDisplayItem *) newsDisplayItemWithNewsId:(NSString *) newsId {
for (NewsDisplayItem *newsDisplayItem in _mNewsDisplayItemList) {
if (newsDisplayItem.newsDisplayParamItemList.count > ) {
NewsDisplayParamItem *displayParamItem = newsDisplayItem.newsDisplayParamItemList[];
if ([displayParamItem.newsId isEqualToString:newsId]) {
return newsDisplayItem;
}
}
}
return nil;
} - (NewsDisplayItemDataModel *) newsDisplayItemDataModelWithNewsId:(NSString *) newsId {
for (NewsDisplayItemDataModel *newsDisplayItemDataModel in _mNewsDisplayModelList) {
if ([newsDisplayItemDataModel.newsId isEqualToString:newsId]) {
return newsDisplayItemDataModel;
}
}
return nil;
} - (void) loadSearchKeywordsList {
NSFetchRequest* request=[[NSFetchRequest alloc] init];
NSEntityDescription* keywordModelDescription = [NSEntityDescription entityForName:[self searchKeywordEntityName] inManagedObjectContext:self.managedObjectContext];
[request setEntity:keywordModelDescription];
NSArray* fetchResultList = [self.managedObjectContext executeFetchRequest:request error:nil];
_mSearchKeywordsList = [NSMutableArray arrayWithArray:fetchResultList];
} - (NSString *) searchKeywordEntityName {
return @"NewsSearchKeywordModel";
} - (NewsSearchKeywordModel *) searchDataModelWithKeyword:(NSString *) keyword {
for (NewsSearchKeywordModel *newsSearchKeywordModel in _mSearchKeywordsList) {
if ([newsSearchKeywordModel.keyword isEqualToString:keyword]) {
return newsSearchKeywordModel;
}
}
return nil;
} @end

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