如何在 UIActionSheet 中为按钮设置 valueForKey？

Question

我正在彻底改造一个旧项目，因为他们使用UIActionSheet，我不熟悉它，所以请帮我找出来。

UIActionSheet *popupQuery = [[UIActionSheet alloc] initWithTitle:@"beard Selection" delegate:self cancelButtonTitle:@"Cancel"   destructiveButtonTitle:@""   otherButtonTitles:@"", @"", @"", @"", @"", @"", @"", @"", nil];

    NSLog(@"kishore calculation ");
    [[[popupQuery valueForKey:@"_buttons"] objectAtIndex:0] setImage:[UIImage imageNamed:@"ca1.png"] forState:UIControlStateNormal];
    [[[popupQuery valueForKey:@"_buttons"] objectAtIndex:1] setImage:[UIImage imageNamed:@"ca2.png"] forState:UIControlStateNormal];
    [[[popupQuery valueForKey:@"_buttons"] objectAtIndex:2] setImage:[UIImage imageNamed:@"ca3.png"] forState:UIControlStateNormal];
    [[[popupQuery valueForKey:@"_buttons"] objectAtIndex:3] setImage:[UIImage imageNamed:@"ca4.png"] forState:UIControlStateNormal];
    [[[popupQuery valueForKey:@"_buttons"] objectAtIndex:4] setImage:[UIImage imageNamed:@"ca5.png"] forState:UIControlStateNormal];
    [[[popupQuery valueForKey:@"_buttons"] objectAtIndex:5] setImage:[UIImage imageNamed:@"ca6.png"] forState:UIControlStateNormal];
    [[[popupQuery valueForKey:@"_buttons"] objectAtIndex:6] setImage:[UIImage imageNamed:@"ca7.png"] forState:UIControlStateNormal];
    [[[popupQuery valueForKey:@"_buttons"] objectAtIndex:7] setImage:[UIImage imageNamed:@"ca8.png"] forState:UIControlStateNormal];
    [[[popupQuery valueForKey:@"_buttons"] objectAtIndex:8] setImage:[UIImage imageNamed:@"ca9.png"] forState:UIControlStateNormal];
    [[[popupQuery valueForKey:@"_buttons"] objectAtIndex:9] setImage:[UIImage imageNamed:@"ca10.png"] forState:UIControlStateNormal];

    popupQuery.actionSheetStyle = UIActionSheetStyleBlackOpaque;
    [popupQuery setTag:Cap];
    [popupQuery showInView:self.view];

UIActionSheet 就像UIAlertView，因为他们试图添加按钮，但我收到这样的错误，

由于未捕获的异常“NSUnknownKeyException”而终止应用程序， 原因：'[valueForUndefinedKey:]：这个 类不符合键按钮的键值编码。'

指导我克服这个:)

Answer 1

_buttons 没有出现在公共 Api 中。如果你使用这个苹果不同意你的应用程序。所以根据新概念实现你的代码，像这样

UIAlertController * view=   [UIAlertController
                             alertControllerWithTitle:@"XXX "
                             message:@"pickAnyone"
                             preferredStyle:UIAlertControllerStyleActionSheet];
UIAlertAction* first = [UIAlertAction
                         actionWithTitle:@"abc"
                         style:UIAlertActionStyleDefault
                         handler:^(UIAlertAction * action)
                         {
                             //Do some thing here
                             [view dismissViewControllerAnimated:YES completion:nil];
                         }];
UIAlertAction* second = [UIAlertAction
                          actionWithTitle:@"cde+"
                          style:UIAlertActionStyleDefault
                          handler:^(UIAlertAction * action)
                          {
                              [view dismissViewControllerAnimated:YES completion:nil];
                          }];
   UIAlertAction* third = [UIAlertAction
                       actionWithTitle:@"hhh"
                       style:UIAlertActionStyleDestructive
                       handler:^(UIAlertAction * action)
                       {
                           [view dismissViewControllerAnimated:YES completion:nil];

                       }];
UIAlertAction* cancel = [UIAlertAction
                     actionWithTitle:@"Cancel"
                     style:UIAlertActionStyleDefault
                     handler:^(UIAlertAction * action)
                     {
                     }];

[first setValue:[[UIImage imageNamed:@"abc.png"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] forKey:@"image"];
[second setValue:[[UIImage imageNamed:@"cde+.png"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] forKey:@"image"];
[third setValue:[[UIImage imageNamed:@"hhh"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] forKey:@"image"];

[view addAction:first];
[view addAction:second];
[view addAction:third];     
[view addAction:cancel];

[self presentViewController:view animated:YES completion:nil];
}

Answer 2

此代码使用 KVO 尝试访问 UIActionSheet 类的私有属性。这是个坏主意，可能会导致您的应用被应用商店拒绝。

这是个坏主意，因为它依赖于 Apple 框架的私有实现细节。在这种情况下，它可能停止工作，因为 Apple 更改了这些私有实现细节。