使UIAlertView阻止

Question

我需要UIAlertView阻止.因为我有功能,我需要返回UIAlertView选择.但问题是显示后UIAlertView我的功能代码进一步执行所以我无法UIAlertView选择(我可以在委托方法中执行,但我需要返回函数结果).

我试图UIAlertVIew阻止NSCondition.但代码不起作用.

condition = [NSCondition new];
result = 0 ; 
[condition lock];
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Fingerprint" message:@"test" delegate:window_self cancelButtonTitle:@"No" otherButtonTitles:@"Yes",nil];
[alert setDelegate:self];
[alert show];
while (result == 0) [condition wait];
[condition unlock] ;

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
 [condition lock] ;
 if (buttonIndex == 0)
 {
  result = 2; 
 }
 else if (buttonIndex == 1)
 {
  result = 3 ;
 }
 [condition signal] ;
 [condition unlock] ;
}

也许如何修复此代码或任何其他建议？谢谢

Answer 1

没有办法实现你想要的.只有通过代表.您应该重新设计您的功能或拒绝使用UIAlertView

Answer 2

这不会阻止它,但是我已经编写了一个子类来添加块样式语法,如果你在一个类中有多个UIAlertViews,它可以更容易地处理buttonClickedAtIndex方法而不必执行委托和一大堆if语句.

#import <UIKit/UIKit.h>

@interface UIAlertViewBlock : UIAlertView<UIAlertViewDelegate>
- (id) initWithTitle:(NSString *)title message:(NSString *)message block: (void (^)(NSInteger buttonIndex))block
   cancelButtonTitle:(NSString *)cancelButtonTitle otherButtonTitles:(NSString *)otherButtonTitles, ... NS_AVAILABLE(10_6, 4_0);
@end


#import "UIAlertViewBlock.h"

@interface UIAlertViewBlock()
{
    void (^_block)(NSInteger);
}
@end

@implementation UIAlertViewBlock

- (id) initWithTitle:(NSString *)title message:(NSString *)message block: (void (^)(NSInteger buttonIndex))block
cancelButtonTitle:(NSString *)cancelButtonTitle otherButtonTitles:(NSString *)otherButtonTitles, ... NS_AVAILABLE(10_6, 4_0)
{
    if (self = [super initWithTitle:title message:message delegate:self cancelButtonTitle:cancelButtonTitle otherButtonTitles:otherButtonTitles, nil])
    {
        _block = block;
    }
    return self;
}

- (void) alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
    _block(buttonIndex);
}

@end

然后在这里调用它是一些示例代码.另一个很酷的部分是,因为一个块关闭局部变量,我可以访问我显示UIAlertView时存在的所有状态.使用传统的委托方法,您必须将所有临时状态存储到类级变量中,以便在委托中对buttonClickedAtIndex的调用中访问它.这太清洁了.

{
    NSString *value = @"some random value";
    UIAlertViewBlock *b = [[UIAlertViewBlock alloc] initWithTitle:@"Title" message:@"Message" block:^(NSInteger buttonIndex)
        {
            if (buttonIndex == 0)
                NSLog(@"%@", [value stringByAppendingString: @" Cancel pressed"]);
            else if (buttonIndex == 1)
                NSLog(@"Other pressed");
            else
                NSLog(@"Something else pressed");
        }
        cancelButtonTitle:@"Cancel" otherButtonTitles:@"Other", nil];

    [b show];
}