Replace common iOS delegate APIs with blocks

iOS_API+Blocks.h

//
//  iOS_API+Blocks.h
//
//  Created by Bobby Schultz on 12/1/11.

@interface UIAlertView (PBBlocks)

+ (id) alertWithTitle:(NSString*)title 
              message:(NSString*)message
         clickedBlock:(void(^)(NSInteger))buttonIndexClickedBlock
    cancelButtonTitle:(NSString*)cancelButtonTitle
    otherButtonTitles:(NSString*)otherButtonTitles;
@end

iOS_API+Blocks.m

//
//  iOS_API+Blocks.m
//
//  Created by Bobby Schultz on 12/1/11.

// Generic Block Delegate
@interface DelegateBlock:NSObject
typedef void (^HeapBlock)(NSInteger);
@property (nonatomic, copy) HeapBlock callbackBlock; 
@end

@implementation DelegateBlock
@synthesize callbackBlock;
- (id) initWithBlock:(void(^)(NSInteger))callback
{
    // Init and copy Callback Block to the heap (@see accessor)
    if (self = [super init]) 
        [self setCallbackBlock:callback];
    return [self autorelease];
}
- (void) dealloc
{
    // Release the block
    [callbackBlock release], callbackBlock = nil;    
    [super dealloc];
}
- (void) alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
    // Return the result to the callback
    callbackBlock(buttonIndex);
    
    // Detach the block delegate, will decrement retain count
    SEL key = @selector(alertWithTitle:message:clickedBlock:cancelButtonTitle:otherButtonTitles:);
    objc_setAssociatedObject(alertView, key, nil, OBJC_ASSOCIATION_RETAIN);
    key = nil;
    
    // Release the Alert
    [alertView release];
}
@end

// Alert View Category
//
// @example __block BOOL shouldHide = NO;
//        [UIAlertView alertWithTitle:@"Danger!" 
//                            message:@"Danger Will Robinson!" 
//                       clickedBlock:^(NSInteger buttonIndex){
//                                  if (buttonIndex == 1) {
//                                      shouldHide = YES;
//                                  }
//                              } 
//                  cancelButtonTitle:@"Run" 
//                  otherButtonTitles:@"Hide"];
//
@implementation UIAlertView (PBBlocks)

+ (id) alertWithTitle:(NSString*)title
              message:(NSString*)message
         clickedBlock:(void(^)(NSInteger))buttonIndexClickedBlock
    cancelButtonTitle:(NSString*)cancelButtonTitle
    otherButtonTitles:(NSString*)otherButtonTitles
{
    // Create class to hold delegatee and copy block to heap
    DelegateBlock *delegatee = [[DelegateBlock alloc] initWithBlock:buttonIndexClickedBlock];
    [[delegatee retain] autorelease];
    // Create delegater
    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:title 
                                                    message:message 
                                                   delegate:delegatee
                                          cancelButtonTitle:cancelButtonTitle 
                                          otherButtonTitles:otherButtonTitles, nil];
    
    // Attach the Delegate Block class to the Alert View, increase the retain count
    objc_setAssociatedObject(alert, _cmd, delegatee, OBJC_ASSOCIATION_RETAIN);
    
    // Display the alert
    [alert show];
    return alert;
}

@end