iphone - 阻止UIAlertViewDelegate

我对 objective-c 还是很陌生，我只是想弄清楚是否可以将块或选择器用作UIAlertView的UIAlertViewDelegate参数-哪个更合适？

我已经尝试了以下方法，但是它无法正常工作，所以我不确定是否在正确的轨道上？

    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Checked In"
    message:responseString
    delegate:^(UIAlertView * alertView, NSInteger buttonIndex)
                                                    {
                                                       NSLog(@"Done!");
                                                   }
    cancelButtonTitle:@"OK"
    otherButtonTitles: nil];

谢谢!

最佳答案

好点子。这里是。就像警报 View 一样，区别在于添加了一个块属性，该属性在警报被消除时被调用。 (编辑-自原始答案以来，我已简化了此代码。这是我现在在项目中使用的代码)

//  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

您可以将此思想扩展到为其他委托(delegate)方法提供块，但didDismiss是最常见的。

这样称呼它:

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];

关于iphone - 阻止UIAlertViewDelegate，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/10082383/