UITableView 특유의 2 단계 업데이트

NSFetchedResultsController에 의해 구동되는 UITableView가 있습니다. tableview에는 사용자 정의 꼬리말보기가 있으며, API에서 데이터를 가져와 응답을 코어 데이터에 매핑하는 데 RestKit을 사용하고 있습니다.UITableView 특유의 2 단계 업데이트

RestKit 요청이 반환 된 후 응답이 핵심 데이터로 매핑되고 FetchedResultsController가 대리자 (내 tableview 컨트롤러) 업데이트를 보내고 tableview가 부분적으로 업데이트되는 경우가 매우 적습니다. 1 초. 그런 다음 몇 초 후 tableview 업데이트가 완료됩니다. 첫 번째로 tablefooterview가 다시 그려지지 않으며 그 아래에 셀이 추가되기 때문에 tableview가 부분적으로 업데이트됩니다. 꼬리말이 자리로 옮겨지기까지는 그렇게되지 않습니다.

저는 계측기로 앱을 프로파일 링 해 보았습니다. 그리기/로딩 셀에서 CPU 기반 지연이 아닌 것 같습니다. 또한 복잡성을 최소화하기 위해 셀을 구성 할 때만 셀의 제목 레이블을 설정하기 만했습니다. 또한 장치와 시뮬레이터에서 동일한 동작을 볼 수 있습니다.

나는 정말 나쁜 사용자 경험을 유발하기 때문에이 지연을 추적하여 제거하고 싶습니다.

로그에서 제외하고 :

2012-09-18 10:39:43.695 MyApp[28881:470f] -[RDRMarketBooksViewController controllerWillChangeContent:] [Line 236] controller => <NSFetchedResultsController: 0xe657570> 
2012-09-18 10:39:43.695 MyApp[28881:470f] -[RDRMarketBooksViewController controller:didChangeObject:atIndexPath:forChangeType:newIndexPath:] [Line 267] controller => <NSFetchedResultsController: 0xe657570> 
(...19 similiar lines...) 
2012-09-18 10:39:43.703 MyApp[28881:470f] -[RDRMarketBooksViewController controllerDidChangeContent:] [Line 301] controller => <NSFetchedResultsController: 0xe657570> 
2012-09-18 10:39:43.705 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xed5f890; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xed5f9b0>>, indexPath => <NSIndexPath 0xed5eab0> 2 indexes [0, 0] 
2012-09-18 10:39:43.706 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xe659e50; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xe659f70>>, indexPath => <NSIndexPath 0xe657b50> 2 indexes [0, 1] 
2012-09-18 10:39:43.708 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xe65aca0; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xe65adc0>>, indexPath => <NSIndexPath 0xe65a6f0> 2 indexes [0, 2] 
2012-09-18 10:39:43.709 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xe9e1890; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xe9b1e10>>, indexPath => <NSIndexPath 0xe9c59d0> 2 indexes [0, 3] 
2012-09-18 10:39:43.711 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0x13c6f230; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0x13c6ed80>>, indexPath => <NSIndexPath 0xe9e0fb0> 2 indexes [0, 4] 
2012-09-18 10:39:43.712 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xe9e2230; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xe9b1a60>>, indexPath => <NSIndexPath 0xe9e0ea0> 2 indexes [0, 5] 
2012-09-18 10:39:43.713 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0x13c6fef0; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0x13c70010>>, indexPath => <NSIndexPath 0xe95dca0> 2 indexes [0, 6] 
2012-09-18 10:39:43.714 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xeb599f0; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xeb59b10>>, indexPath => <NSIndexPath 0xe9e2a10> 2 indexes [0, 7] 
2012-09-18 10:39:43.715 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0x13c70d10; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0x13c6fea0>>, indexPath => <NSIndexPath 0xe9e1790> 2 indexes [0, 8] 
2012-09-18 10:39:43.717 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xed616c0; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xed5ee80>>, indexPath => <NSIndexPath 0xe9e1d50> 2 indexes [0, 9] 
2012-09-18 10:39:43.718 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xe65bb00; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xe65b680>>, indexPath => <NSIndexPath 0xe65b1c0> 2 indexes [0, 11] 
2012-09-18 10:39:43.720 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0x13c71c00; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0x13c71770>>, indexPath => <NSIndexPath 0x13c6f1d0> 2 indexes [0, 13] 
2012-09-18 10:39:43.721 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xe65c900; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xe65c4a0>>, indexPath => <NSIndexPath 0xe659ce0> 2 indexes [0, 14] 
2012-09-18 10:39:43.722 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xe65d720; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xe65d2c0>>, indexPath => <NSIndexPath 0xe659de0> 2 indexes [0, 15] 
2012-09-18 10:39:43.723 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xe65e5a0; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xe65e110>>, indexPath => <NSIndexPath 0xe65d2a0> 2 indexes [0, 16] 
2012-09-18 10:39:43.739 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0x91bf9e0; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0x9197560>>, indexPath => <NSIndexPath 0x91c9960> 2 indexes [0, 17] 
2012-09-18 10:39:43.740 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0x93e8d50; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0x93dd090>>, indexPath => <NSIndexPath 0x93cb8b0> 2 indexes [0, 18] 
2012-09-18 10:39:43.741 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0x13c727b0; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0x13c728d0>>, indexPath => <NSIndexPath 0x13c72420> 2 indexes [0, 19] 
2012-09-18 10:39:43.742 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0x93e6ff0; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0x93da000>>, indexPath => <NSIndexPath 0x93d4d10> 2 indexes [0, 21] 
2012-09-18 10:39:43.744 MyApp[28881:470f] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xed62510; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xed620a0>>, indexPath => <NSIndexPath 0xed5ed80> 2 indexes [0, 22] 
2012-09-18 10:39:43.772 MyApp[28881:c07] -[RDRMarketBooksViewController controllerWillChangeContent:] [Line 236] controller => <NSFetchedResultsController: 0xe657570> 
2012-09-18 10:39:43.777 MyApp[28881:c07] -[RDRMarketBooksViewController controller:didChangeObject:atIndexPath:forChangeType:newIndexPath:] [Line 267] controller => <NSFetchedResultsController: 0xe657570> 
(...19 similiar lines...) 
2012-09-18 10:39:43.788 MyApp[28881:c07] -[RDRMarketBooksViewController controllerDidChangeContent:] [Line 301] controller => <NSFetchedResultsController: 0xe657570> 
2012-09-18 10:39:43.790 MyApp[28881:c07] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0x13c7be10; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0x13c7bf30>>, indexPath => <NSIndexPath 0x13c7b080> 2 indexes [0, 0] 
2012-09-18 10:39:43.791 MyApp[28881:c07] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xe9e2be0; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xe9e1b10>>, indexPath => <NSIndexPath 0xe977940> 2 indexes [0, 1] 
2012-09-18 10:39:43.792 MyApp[28881:c07] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xe9e38b0; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xe9e2190>>, indexPath => <NSIndexPath 0xe9c0bc0> 2 indexes [0, 2] 
2012-09-18 10:39:43.793 MyApp[28881:c07] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0xe9e4680; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0xe9e41f0>>, indexPath => <NSIndexPath 0xe9e3d60> 2 indexes [0, 3] 
2012-09-18 10:39:43.794 MyApp[28881:c07] -[RDRMarketBooksViewController configureCell:atIndexPath:] [Line 34] cell => <RDRMarketBooksCell: 0x13c7ccc0; baseClass = UITableViewCell; frame = (0 0; 320 79); autoresize = W+BM; layer = <CALayer: 0x13c7cde0>>, indexPath => <NSIndexPath 0x13c7b270> 2 indexes [0, 4] 
2012-09-18 10:39:43.802 MyApp[28881:c07] -[RDRMarketBooksViewController productsDidLoad:forCategory:error:] [Line 319] resource => <RDRRangedResource: 0x9533390> => {

그리고 내있는 UITableViewController 하위 클래스에서 해당 방법 :

- (void)configureCell:(RDRMarketBooksCell *)cell atIndexPath:(NSIndexPath *)indexPath { 
    NSParameterAssert(cell); 
    NSParameterAssert(indexPath); 

    Trace(@"cell => %@, indexPath => %@", cell, indexPath); 

    NSAssert([cell isKindOfClass:[RDRMarketBooksCell class]], @"should be a market books cell"); 
    id<RDRAPIProduct> product = [fetchedResultsController objectAtIndexPath:indexPath]; 
    cell.titleLabel.text = product.name; 
} 

#pragma mark - 
#pragma mark UITableViewDelegate 

// Configuring Rows for the Table View 

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath { 
    return 79.0; 
} 

- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath { 
    if (!tableViewIsUpdating) { 
     [(RDRMarketBooksCell *)cell refreshSecondaryValues]; 
    } 
} 

// Managing Selections 

- (NSIndexPath *)tableView:(UITableView *)tableView willSelectRowAtIndexPath:(NSIndexPath *)indexPath { 
    id<RDRAPIProduct> product = [fetchedResultsController objectAtIndexPath:indexPath]; 

    BOOL shouldSelect = YES; 
    if (product) { 
     shouldSelect = (product.slug != nil); 
    } 
    return (shouldSelect ? indexPath : nil); 
} 

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { 
    id<RDRAPIProduct> product = [fetchedResultsController objectAtIndexPath:indexPath]; 

    if (RDRIsiPad()) { 
     [[RDRApplicationDelegate sharedDelegate] presentDetailsWithProduct:product]; 
    } 

    [self.delegate viewController:self didPickProduct:product]; 

    [tableView deselectRowAtIndexPath:indexPath animated:YES]; 
} 

#pragma mark - 
#pragma mark UITableViewDataSource 

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { 

    RDRMarketBooksCell *cell = [tableView dequeueReusableCellWithIdentifier:kRDRMarketBooksCellIdentifier]; 
    NSAssert(cell, @"cell should not be nil"); 

    [self configureCell:cell atIndexPath:indexPath]; 

    return cell; 
} 

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { 
    return [[fetchedResultsController sections] count]; 
} 

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { 
    id <NSFetchedResultsSectionInfo> sectionInfo = [[fetchedResultsController sections] objectAtIndex:section]; 
    return [sectionInfo numberOfObjects]; 
} 

#pragma mark - 
#pragma mark NSFetchedResultsControllerDelegate 

/* 
Assume self has a property 'tableView' -- as is the case for an instance of a UITableViewController 
subclass -- and a method configureCell:atIndexPath: which updates the contents of a given cell 
with information from a managed object at the given index path in the fetched results controller. 
*/ 

- (void)controllerWillChangeContent:(NSFetchedResultsController *)controller { 
    Trace(@"controller => %@", controller); 
    if (controller == fetchedResultsController) { 
     tableViewIsUpdating = YES; 
     [self.tableView beginUpdates]; 
    } 
} 


- (void)controller:(NSFetchedResultsController *)controller didChangeSection:(id <NSFetchedResultsSectionInfo>)sectionInfo 
      atIndex:(NSUInteger)sectionIndex forChangeType:(NSFetchedResultsChangeType)type { 
    Trace(@"controller => %@", controller); 

    if (controller == fetchedResultsController) { 
     switch(type) { 
      case NSFetchedResultsChangeInsert: 
       [self.tableView insertSections:[NSIndexSet indexSetWithIndex:sectionIndex] 
           withRowAnimation:UITableViewRowAnimationFade]; 
       break; 

      case NSFetchedResultsChangeDelete: 
       [self.tableView deleteSections:[NSIndexSet indexSetWithIndex:sectionIndex] 
           withRowAnimation:UITableViewRowAnimationFade]; 
       break; 
     } 
    } 
} 


- (void)controller:(NSFetchedResultsController *)controller didChangeObject:(id)anObject 
     atIndexPath:(NSIndexPath *)indexPath forChangeType:(NSFetchedResultsChangeType)type 
     newIndexPath:(NSIndexPath *)newIndexPath { 
    Trace(@"controller => %@", controller); 

    if (controller == fetchedResultsController) { 
     UITableView *tableView = self.tableView; 

     switch(type) { 

      case NSFetchedResultsChangeInsert: 
       [tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] 
           withRowAnimation:UITableViewRowAnimationFade]; 
       break; 

      case NSFetchedResultsChangeDelete: 
       [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] 
           withRowAnimation:UITableViewRowAnimationFade]; 
       break; 

      case NSFetchedResultsChangeUpdate: 
       [tableView reloadRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] 
           withRowAnimation:UITableViewRowAnimationFade]; 
       break; 

      case NSFetchedResultsChangeMove: 
       [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] 
           withRowAnimation:UITableViewRowAnimationFade]; 
       [tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] 
           withRowAnimation:UITableViewRowAnimationFade]; 
       break; 
     } 
    } 
} 


- (void)controllerDidChangeContent:(NSFetchedResultsController *)controller { 
    Trace(@"controller => %@", controller); 
    if (controller == fetchedResultsController) { 
     [self.tableView endUpdates]; 
     tableViewIsUpdating = NO; 

//  double delayInSeconds = 0.1; 
//  dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, delayInSeconds * NSEC_PER_SEC); 
//  dispatch_after(popTime, dispatch_get_main_queue(), ^(void){ 
//   [self fetchSecondaryValues]; 
//  }); 
    } 
}

출처

2012-09-18 Philip Kuryloski

해결. NSFetchedResultsController는 RKManagedObjectStore의 primaryManagedObjectContext를 사용하고있었습니다. mainQueueManagedObjectContext로 전환하여 문제가 해결되었습니다.

RestKit을 자세히 살펴보면 mainQueueManagedObjectContext는 primaryManagedObjectContext의 하위 항목이며이 사실이 문서에 언급되어 있음을 알게되었습니다. 나는 원래 RestKit 매핑이 primaryManagedObjectContext에서 발생한다고 생각했지만, 이제는 내 생각에 mainQueueManagedObjectContext에서 발생하고 primaryManagedObjectContext에 낮은 우선 순위의 스레드에 저장된 다음 영구 저장소에 저장됩니다. NSFetchedResultsController를 이전에 primaryManagedObjectContext에 연결하면 결과가 완전히 나타나기 전에 긴 지연이 발생합니다. 이 경우 mainQueueManagedObjectContext를 사용할 필요는 문서에서 분명하지 않습니다. 그러나, docs는 mainQueueManagedObjectContext의 목적은 UI를 더듬지 않게하면서 primaryManagedObjectContext를 통해 영구 저장소에 데이터를 쓸 수 있도록한다는 것을 언급합니다.

이

NSManagedObjectContext *context = [[RKManagedObjectStore defaultStore] mainQueueManagedObjectContext]; 
    NSFetchRequest *fr = [NSFetchRequest fetchRequestWithEntityName:@"RDRProduct"]; 
    fr.fetchBatchSize = 20; 
    fr.predicate = [NSPredicate predicateWithFormat:@"ANY categories.slug == %@", category.slug]; 
    fr.sortDescriptors = [NSArray arrayWithObject:[NSSortDescriptor sortDescriptorWithKey:@"sortingTitle" ascending:YES]]; 
    [NSFetchedResultsController deleteCacheWithName:category.slug]; 
    NSFetchedResultsController *fetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fr 
                           managedObjectContext:context 
                           sectionNameKeyPath:@"sortingSection" 
                              cacheName:category.slug];

내있는 tableview가 정상적으로 작동 :처럼 지금 NSFetchedResultsController를 만들 수

내 코드 보인다.

출처

2012-09-19 07:42:54

나는 당신을 사랑합니다 http://xkcd.com/979/ –

UITableView 특유의 2 단계 업데이트

답변

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