Question

I am working with a core database to save my data that I get back from a webservice into my app. But this is very very slow. Any idea how this comes? What I do is the following. I have a class for getting the data from the webservice. like you can see over here.

     GenkData.h 

            + (NSArray *)getNews;
     GenkData.m
+ (NSDictionary *)executeGenkFetch:(NSString *)query
{
    query = [NSString stringWithFormat:@"%@", query];
    query = [query stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
    // NSLog(@"[%@ %@] sent %@", NSStringFromClass([self class]), NSStringFromSelector(_cmd), query);
    NSData *jsonData = [[NSString stringWithContentsOfURL:[NSURL URLWithString:query] encoding:NSUTF8StringEncoding error:nil] dataUsingEncoding:NSUTF8StringEncoding];
    NSError *error = nil;
    NSDictionary *results = jsonData ? [NSJSONSerialization JSONObjectWithData:jsonData options:NSJSONReadingMutableContainers|NSJSONReadingMutableLeaves error:&error] : nil;
    if (error) NSLog(@"[%@ %@] JSON error: %@", NSStringFromClass([self class]), NSStringFromSelector(_cmd), error.localizedDescription);
    // NSLog(@"[%@ %@] received %@", NSStringFromClass([self class]), NSStringFromSelector(_cmd), results);
    return results;
}

+ (NSArray *)getNews
{
    NSString *request = [NSString stringWithFormat:@"http://www.krcgenk.be/mobile/json/request/news/type/ipad"];
    return [[self executeGenkFetch:request] valueForKey:@"news"];
}

Then in my first view controller that shows up I have a method that for fetching my data in my core database.

- (void)fetchGenkDataIntoDocument:(UIManagedDocument *)document
{
    NSLog(@"Fetch data");
    dispatch_queue_t fetchQ = dispatch_queue_create("Genk fetcher", NULL);
    dispatch_async(fetchQ, ^{

        NSArray *news           = [GenkData getNews];

        [document.managedObjectContext performBlock:^{ // perform in the NSMOC's safe thread (main thread)

            int newsId          = 0;
            //int trainingIndex   = -1;
            for (NSDictionary *genkInfo in news) {
                NSLog(@"Begint met nieuwsitem");
                newsId++;
               [News newsWithGenkInfo:genkInfo inManagedObjectContext:document.managedObjectContext withNewsId:newsId];
                NSLog(@"Einde met nieuwsitem");
            }
 }];
    });
    NSLog(@"einde fethdata");
}

Next I have a category of the NSManagerd object subclass of news where I do the following.

+ (News *)newsWithGenkInfo:(NSDictionary *)genkInfo
    inManagedObjectContext:(NSManagedObjectContext *)context
                withNewsId:(int)newsId
{
    News *news = nil;

    news = [NSEntityDescription insertNewObjectForEntityForName:@"News"
                                                     inManagedObjectContext:context];

    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc]init];
    [dateFormatter setDateFormat:@"dd/MM/yyyy"];
    [dateFormatter setTimeZone:[NSTimeZone timeZoneWithAbbreviation:@"GMT+0:00"]];
        NSDate *date = [dateFormatter dateFromString:[genkInfo objectForKey:NEWS_DATE]];
        news.title              = [genkInfo objectForKey:NEWS_TITLE];
        news.date               = date;
        news.genk_description   = [genkInfo objectForKey:NEWS_DESCRIPTION];
        news.imgurl             = [genkInfo objectForKey:NEWS_IMGURL];
        news.shortdescription   = [genkInfo objectForKey:NEWS_SHORTDESCRIPTION];
        news.url                = [genkInfo objectForKey:NEWS_URL];
        news.imagecopyright     = [genkInfo objectForKey:NEWS_IMAGECOPYRIGHT];
        news.news_id            = [NSNumber numberWithInt:newsId];

    return news;

}

I am doing the following proces like 10 times for 10 different entities. All of those attributes are mostly strings. Still this takes up to 10 minutes to load in all the data. Can somebody help me ?

Kind regards.

Answer 1

Dima’s answer of checking with the profiler helped me with this question and solved my problem