UIAlertView subclass for block based handling of simple alert messages. Send in a title and message and specify a block to be called when the alert is dismissed.

Alert.h

//
//  Alert.h
//
//  Created by Brian Norton on 1/4/14.
//  Copyright (c) 2014 Brian Norton. MIT.
//

#import <UIKit/UIKit.h>

@interface Alert : UIAlertView <UIAlertViewDelegate> {
    void(^block)(BOOL);

    id sself;
}

+(void)alertTitled:(NSString *)title message:(NSString *)message done:(void (^)(BOOL oked))done;

Alert.m

//
//  Alert.m
//
//  Created by Brian Norton on 1/4/14.
//  Copyright (c) 2014 Brian Norton. MIT.
//

#import "Alert.h"

#define CANCEL_INDEX 0

@implementation Alert

+(void)alertTitled:(NSString *)t message:(NSString *)m done:(void (^)(BOOL))done {
    Alert *alert = [[self alloc] initWithTitle:t message:m done:done];

    [alert show];
}

-(id)initWithTitle:(NSString *)title message:(NSString *)message done:(void (^)(BOOL))done {
    self = [super initWithTitle:title message:message delegate:nil
          cancelButtonTitle:@"Cancel" otherButtonTitles:@"Ok", nil];

    if(!self) return nil;

    sself = self;
    block = done;

    self.delegate = self;

    return self;
}

-(void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex {
    sself = nil;

    if(block)
        block(buttonIndex != CANCEL_INDEX);
}

@end