Block for UIAlertViewDelegate

Question

I\'m pretty new to objective C and I\'m just trying to figure out if I can use a block or a selector as the UIAlertViewDelegate argument for UIAlertView - and which is more

Answer 1

Great idea. Here it is. Just like alert view, except adds a block property that's invoked when the alert is dismissed. (Edit - I've simplified this code since the original answer. Here's what I use now in projects)

//  AlertView.h
//

#import <UIKit/UIKit.h>

@interface AlertView : UIAlertView

@property (copy, nonatomic) void (^completion)(BOOL, NSInteger);

- (id)initWithTitle:(NSString *)title message:(NSString *)message cancelButtonTitle:(NSString *)cancelButtonTitle otherButtonTitles:(NSArray *)otherButtonTitles;

@end

//
//  AlertView.m

#import "AlertView.h"

@interface AlertView () <UIAlertViewDelegate>

@end

@implementation AlertView

- (id)initWithTitle:(NSString *)title message:(NSString *)message cancelButtonTitle:(NSString *)cancelButtonTitle otherButtonTitles:(NSArray *)otherButtonTitles {

    self = [self initWithTitle:title message:message delegate:self cancelButtonTitle:cancelButtonTitle otherButtonTitles:nil];

    if (self) {
        for (NSString *buttonTitle in otherButtonTitles) {
            [self addButtonWithTitle:buttonTitle];
        }
    }
    return self;
}

- (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex {

    if (self.completion) {
        self.completion(buttonIndex==self.cancelButtonIndex, buttonIndex);
        self.completion = nil;
    }
}

@end

You can extend this idea to supply blocks for other delegate methods, but the didDismiss is the most common.

Call it like this:

AlertView *alert = [[AlertView alloc] initWithTitle:@"Really Delete" message:@"Do you really want to delete everything?" cancelButtonTitle:@"Nevermind" otherButtonTitles:@[@"Yes"]];

alert.completion = ^(BOOL cancelled, NSInteger buttonIndex) {
    if (!cancelled) {
        [self deleteEverything];
    }
};
[alert show];

Answer 2

Simply use REKit. It's similar to BlocksKit, but it's more powerful.

Answer 3

Check out UIAlertView-Blocks category on Github. I wrote this and is very easy to use and works well.

Good luck.

Answer 4

Here is my implementation, seems like it's similar to most answers here: http://stavash.wordpress.com/2013/01/31/quick-tip-uialertview-with-a-block-callback/

Answer 5

Here is another useful library to do the same. http://bit.ly/ichalrtvw

Code here: http://bit.ly/ichalertview

Answer 6

Check out this UIAlertView-Blocks category on github. I use this and it works well.