Medium/UISheetPresentationController/3.m

UISheetPresentationController_3.m

typedef NSString *SASheetPresentationControllerDetendIdentifier NS_TYPED_EXTENSIBLE_ENUM
API_AVAILABLE(ios(13.0)) API_UNAVAILABLE(tvos, watchos);

UIKIT_EXTERN const SASheetPresentationControllerDetendIdentifier SASheetPresentationControllerDetentIdentifierMaximum
API_AVAILABLE(ios(13.0)) API_UNAVAILABLE(tvos, watchos);

UIKIT_EXTERN const SASheetPresentationControllerDetendIdentifier SASheetPresentationControllerDetentIdentifierLarge
API_AVAILABLE(ios(13.0)) API_UNAVAILABLE(tvos, watchos);

UIKIT_EXTERN const SASheetPresentationControllerDetendIdentifier SASheetPresentationControllerDetentIdentifierMedium
API_AVAILABLE(ios(13.0)) API_UNAVAILABLE(tvos, watchos);

UIKIT_EXTERN const SUISheetPresentationControllerDetendIdentifier SASheetPresentationControllerDetentIdentifierSmall
API_AVAILABLE(ios(13.0)) API_UNAVAILABLE(tvos, watchos);

typedef CGFloat (^SASheetDetentResulutionBlock)(UIView *containerView, CGRect availableCoordinateSpace);

API_AVAILABLE(ios(13.0)) API_UNAVAILABLE(tvos, watchos) NS_SWIFT_UI_ACTOR
@interface SUISheetPresentationControllerDetent : NSObject

+ (instancetype)detentWithIdentifier:(SASheetPresentationControllerDetendIdentifier)identifier
                     resolutionBlock:(SASheetDetentResulutionBlock)resolutionBlock;

+ (instancetype)largeDetent;
+ (instancetype)mediumDetent;
+ (instancetype)smallDetent;

@end

static Class kSA13SheetPresentationControllerDetentClass = nil;

const SASheetPresentationControllerDetendIdentifier SASheetPresentationControllerDetentIdentifierMaximum = @"com.apple.UIKit.maximum";
const SASheetPresentationControllerDetendIdentifier SASheetPresentationControllerDetentIdentifierLarge = @"com.apple.UIKit.large";
const SASheetPresentationControllerDetendIdentifier SASheetPresentationControllerDetentIdentifierMedium = @"com.apple.UIKit.medium";
const SASheetPresentationControllerDetendIdentifier SASheetPresentationControllerDetentIdentifierSmall = @"com.apple.UIKit.small";

@interface SASheetPresentationControllerDetent ()

@property (nonatomic, copy) SASheetPresentationControllerDetendIdentifier identifier;
@property (nonatomic, copy) SASheetDetentResulutionBlock resulutionBlock;
@property (nonatomic, strong) id presentationControllerDetent;

@end

@implementation SASheetPresentationControllerDetent

+ (void)load
{
  static dispatch_once_t onceToken;
  dispatch_once(&onceToken, ^{
    kSA13SheetPresentationControllerDetentClass = NSClassFromString(@"_UISheetDetent");
  });
}

- (instancetype)initWithPresentationControllerDetent:(id)presentationControllerDetent
                                          identifier:(SASheetPresentationControllerDetendIdentifier)identifier
                                     resulutionBlock:(SASheetDetentResulutionBlock _Nullable)resulutionBlock
{
  self = [super init];
  if (self != nil) {
    _identifier = [identifier copy];
    _resulutionBlock = [resulutionBlock copy];
    _presentationControllerDetent = presentationControllerDetent;
  }
  return self;
}

+ (instancetype)detentWithIdentifier:(SUISheetPresentationControllerDetendIdentifier)identifier
                     resolutionBlock:(SUISheetDetentResulutionBlock)resolutionBlock
{
  id presentationControllerDetent = nil;
    
  if (@available(iOS 15, *)) {
    Class klass = [UISheetPresentationControllerDetent class];
    presentationControllerDetent = [[klass alloc] init];
  } else {
    presentationControllerDetent = [[kSA13SheetPresentationControllerDetentClass alloc] initWithInternalBlock:resolutionBlock];
  }
    
  return [[SASheetPresentationControllerDetent alloc] initWithPresentationControllerDetent:presentationControllerDetent
                                                                                identifier:identifier
                                                                           resulutionBlock:resolutionBlock];
}

+ (instancetype)largeDetent {
    id presentationControllerDetent = nil;
    
    if (@available(iOS 15, *)) {
        presentationControllerDetent = [UISheetPresentationControllerDetent largeDetent];
    } else {
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
        SEL sel = NSSelectorFromString(@"_largeDetent");
        presentationControllerDetent = [kSA13SheetPresentationControllerDetentClass performSelector:sel];
#pragma clang diagnostic pop
    }
    
    return [[SUISheetPresentationControllerDetent alloc] initWithPresentationControllerDetent:presentationControllerDetent
                                                                                   identifier:SUISheetPresentationControllerDetentIdentifierLarge
                                                                              resulutionBlock:nil];
}

+ (instancetype)mediumDetent {
    id presentationControllerDetent = nil;
    
    if (@available(iOS 15, *)) {
        presentationControllerDetent = [UISheetPresentationControllerDetent mediumDetent];
    } else {
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
        SEL sel = NSSelectorFromString(@"_mediumDetent");
        presentationControllerDetent = [kSA13SheetPresentationControllerDetentClass performSelector:sel];
#pragma clang diagnostic pop
    }
    
  return [[SASheetPresentationControllerDetent alloc] initWithPresentationControllerDetent:presentationControllerDetent
                                                                                identifier:SUISheetPresentationControllerDetentIdentifierMedium
                                                                           resulutionBlock:nil];
}

+ (instancetype)smallDetent 
{
  return [self detentWithIdentifier:SUISheetPresentationControllerDetentIdentifierSmall
                    resolutionBlock:^CGFloat (UIView *containerView, CGRect frame) {
    return 121.0f;
  }];
}

#pragma mark -

- (id)forwardingTargetForSelector:(SEL)aSelector 
{
    return self.presentationControllerDetent;
}

@end