Diffable Datasource with Updating Cells - Objective-C

OCDiffable.m

//
//  ViewController.m
//  UpdatingCells
//
//  Created by Joss Manger on 9/6/21.
//

#import "ViewController.h"

typedef NS_ENUM(NSInteger, JSYSectionType){
  JSYSectionTypeFirstSection
};

@protocol SectionDataProtocol <NSObject>

@property (readonly) NSString* sectionTitle;
@property (readonly) JSYSectionType sectionType;

@end

@interface JSYSection : NSObject <SectionDataProtocol>{
  NSString* sectionTitle;
  JSYSectionType sectionType;
}

- (instancetype)initNewSection:(NSString *)title and:(JSYSectionType)type;

@end

@implementation JSYSection

@synthesize sectionTitle;
@synthesize sectionType;

- (instancetype)initNewSection:(NSString *)title and:(JSYSectionType)type{
  self = [super init];
  if (self){
    sectionTitle = [[NSString alloc] initWithString:title];
    sectionType = type;
  }
  return self;
}



- (NSString *)description
{
  return [NSString stringWithFormat:@"it's a Section!\n title: %@ type:%ld", sectionTitle, (long)sectionType];
}

@end


@protocol CellDataProtocol <NSObject>

@property BOOL animating;
@property NSString* titleString;

@end

@interface CellData : NSObject <CellDataProtocol>
@property BOOL animating;
@property NSString* titleString;

- (instancetype)initWithString:(NSString*)title withAnimationState:(BOOL)animation;

@end

@implementation CellData

- (instancetype)initWithString:(NSString*)title withAnimationState:(BOOL)animation
{
  self = [super init];
  if (self) {
    _animating = animation;
    _titleString = title;
  }
  return self;
}

@end

@interface JSSYUpdatingCell : UITableViewCell

- (void)setUpdating:(BOOL)updating;
- (void)toggleUpdating:(id<CellDataProtocol>)data;
+(NSString*)identifier;
@end

@implementation JSSYUpdatingCell{
  UIActivityIndicatorView *indicator;
  BOOL isUpdating;
}

+ (NSString *)identifier{
  return @"jssyCell";
}

- (instancetype)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier
{
  self = [super initWithStyle:style reuseIdentifier:reuseIdentifier];
  if (self) {
    isUpdating = NO;
    indicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleLarge];
    [self.contentView addSubview:indicator];
  }
  return self;
}

- (void)setUpdating:(BOOL)updating{
  updating ? [indicator startAnimating] : [indicator stopAnimating];

  __weak JSSYUpdatingCell *weakCell = self;
  [UIView animateWithDuration:1 animations:^{
    JSSYUpdatingCell *strSelf = weakCell;
    CGRect frame = strSelf->indicator.frame;
    if (updating) {
      [strSelf->indicator setCenter:[[strSelf contentView] center]];
    } else {
      [strSelf->indicator setFrame:CGRectMake(0, 0, CGRectGetWidth(frame), CGRectGetHeight(frame))];
    }
    [strSelf.contentView setNeedsLayout];
    [strSelf.contentView layoutIfNeeded];
  }];
  
  NSLog(@"is updating %@",(isUpdating ? @"YES" : @"NO"));
}

- (void)toggleUpdating:(id<CellDataProtocol>)data {
  
  [self setUpdating:data.animating];
}

@end


@interface MyDiffableDataSource : UITableViewDiffableDataSource

@end


@implementation MyDiffableDataSource

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section{
  JSYSection *sectionModel = [[self snapshot] sectionIdentifiers][section];
  return [sectionModel sectionTitle];
}

@end






@interface ViewController ()

@end

@implementation ViewController {
  UITableView *tableView;
  UITableViewDiffableDataSource *dataSource;
}

- (void)viewDidLoad {
  [super viewDidLoad];
  tableView = [[UITableView alloc] initWithFrame:self.view.bounds style:UITableViewStyleGrouped];
  [tableView setAutoresizingMask:UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight];
  
  [tableView registerClass:[JSSYUpdatingCell class] forCellReuseIdentifier:[JSSYUpdatingCell identifier]];
  
  [self.view addSubview:tableView];
  
  UITableViewDiffableDataSourceCellProvider provider = ^UITableViewCell * _Nullable(UITableView *tableView, NSIndexPath *path, id something) {
    
    JSSYUpdatingCell *cell = [tableView dequeueReusableCellWithIdentifier:[JSSYUpdatingCell identifier]];
    CellData* cellData = (CellData*)something;
    [cell.textLabel setText:cellData.titleString];
    
    return cell;
    
  };
  
  dataSource = [[MyDiffableDataSource alloc] initWithTableView:tableView cellProvider: provider];
  
  [tableView setDataSource:dataSource];
  __weak id<UITableViewDelegate> delegate = (id<UITableViewDelegate>)self;
  [tableView setDelegate:delegate];
  
  NSDiffableDataSourceSnapshot *snapshot = [dataSource snapshot];
  
  JSYSection *section = [[JSYSection alloc] initNewSection:@"SECTION!" and:JSYSectionTypeFirstSection];
  
  [snapshot appendSectionsWithIdentifiers:@[section]];
  [snapshot appendItemsWithIdentifiers:@[
    [[CellData alloc] initWithString:@"Hello" withAnimationState:YES],
    [[CellData alloc] initWithString:@"World" withAnimationState:NO],
    [[CellData alloc] initWithString:@"Jossy" withAnimationState:NO]
  ]];
   
  __weak ViewController *weakSelf = self;
   dispatch_async(dispatch_get_main_queue(), ^{
     ViewController *strongSelf = weakSelf;
     [strongSelf->dataSource applySnapshot:snapshot animatingDifferences:YES];
   });
   
  // Do any additional setup after loading the view.
}


@end

@interface ViewController (ViewControllerConformingToDelegate) <UITableViewDelegate>

@end

@implementation ViewController (ViewControllerConformingToDelegate)

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{
  NSLog(@"oh hello %@",indexPath);
  JSSYUpdatingCell *cell = [tableView cellForRowAtIndexPath:indexPath];
  CellData* cellData = [dataSource itemIdentifierForIndexPath:indexPath];
  [cellData setAnimating:!cellData.animating];
  [cell toggleUpdating:cellData];
  
}

@end

added custom cell type with readonly properties