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POiOS iPhone Core Data how to find an object within a to many relationship using a specific property?
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copied!<p>I got a core data entity named Application, and it can have multiple screenshots added to it as a set. Each screenshot has an "order" attribute, which I'm hoping to use to pull only the first screenshot out of each set. </p> <p>Below is the code that I'm currently using, but <strong>maybe there's something easier/more efficient that I can use to pull out a screenshot with a particular order from a -to many relationship?</strong> </p> <pre><code> if(managedObject.screenshots.count>0) { //search for a screenshot NSMutableArray* predicatesArray = [[NSMutableArray alloc] initWithCapacity:2]; [predicatesArray addObject: [NSPredicate predicateWithFormat:@"SELF.order == %d",0]]; [predicatesArray addObject: [NSPredicate predicateWithFormat:@"SELF.application == %@",managedObject]]; NSPredicate* compoundPredicate = [NSCompoundPredicate andPredicateWithSubpredicates: predicatesArray]; NSFetchRequest *firstScreenshot = [NSFetchRequest fetchRequestWithEntityName:@"Screenshot"]; firstScreenshot.predicate = compoundPredicate; NSError* error; NSArray* results = [managedObject.managedObjectContext executeFetchRequest:firstScreenshot error:&error]; if(error) { DLog(@"%@",[error localizedDescription]); } //if we got a result if(results.count>0) { Screenshot* screenshot = [results objectAtIndex:0]; cell.screenshot.image = [UIImage imageWithData:screenshot.image]; }else { cell.screenshot.image = [UIImage imageNamed:@"blank1.png"]; } } </code></pre>

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