iOS 8 中的 AlertView 问题

Question

我在 AlertView 中添加了一个 UIVIew，如下所示：

UIView *alertSubView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 260, 55)];
        [alertSubView addSubview:textField];
        [alertSubView addSubview:charLeftLabel];

        [alert setValue:alertSubView forKey:@"accessoryView"];

问题

UIView* alertSubView = [alertView valueForKey:@"accessoryView"];

当我尝试在 Alertview 委托方法中获取该子视图时，应用程序崩溃。

它在 iOS7 中运行良好，但仅在 iOS 8 中存在问题

错误由于未捕获的异常“NSUnknownKeyException”而终止应用程序，原因：“[valueForUndefinedKey:]：该类不符合键附件视图的键值编码。

Answer 1

警报视图已弃用。您应该使用UIAlertController。这只是一个建议。

例如作为你的方面：

UIAlertController *alertController = [UIAlertController
                                      alertControllerWithTitle:@"Alert Controller"
                                      message:@"Alert Message"
                                      preferredStyle:UIAlertControllerStyleAlert];

UIViewController *viewController = [[UIViewController alloc]init];
[viewController.view setBackgroundColor:[UIColor blueColor]];

UILabel *lbl = [[UILabel alloc]initWithFrame:CGRectMake(10, 8, 250, 30)];
lbl.text = @"This is a label";
lbl.textAlignment = NSTextAlignmentCenter;
lbl.textColor = [UIColor whiteColor];
[viewController.view addSubview:lbl];

UITextField *tf = [[UITextField alloc]initWithFrame:CGRectMake(10, 35, 250, 30)];
tf.borderStyle = UITextBorderStyleRoundedRect;
tf.placeholder = @"Enter your name";
[viewController.view addSubview:tf];

[alertController setValue:viewController forKey:@"contentViewController"];

UIAlertAction *cancelAction = [UIAlertAction
                               actionWithTitle:@"Cancel"
                               style:UIAlertActionStyleCancel
                               handler:^(UIAlertAction *action)
                               {
                                   NSLog(@"Cancel action");
                               }];

UIAlertAction *okAction = [UIAlertAction
                           actionWithTitle:@"OK"
                           style:UIAlertActionStyleDefault
                           handler:^(UIAlertAction *action)
                           {
                               NSLog(@"OK action");

                               NSLog(@"Text Value : %@",tf.text);
                           }];

[alertController addAction:cancelAction];
[alertController addAction:okAction];

dispatch_async(dispatch_get_main_queue(), ^{
    [self presentViewController:alertController animated:YES completion:nil];
});

希望对你有帮助。

Answer 2

你可以在 swift 2.0 中做同样的事情，就像下面的代码：

let alert = UIAlertController(title: "Alert Controller", message: "Alert Message", preferredStyle: UIAlertControllerStyle.Alert)


let cancelAction = UIAlertAction(
    title: "Cancel",
    style: UIAlertActionStyle.Destructive) { (action) in

}

let confirmAction = UIAlertAction(
    title: "OK", style: UIAlertActionStyle.Default) { (action) in

}

alert.addAction(confirmAction)
alert.addAction(cancelAction)

let VC = UIViewController()
VC.view.backgroundColor = UIColor.blackColor()


let lbl =  UILabel()
lbl.frame =  CGRectMake(10, 8, 250, 30)
lbl.text = "this is a label"
lbl.textAlignment = NSTextAlignment.Center
lbl.textColor = UIColor.whiteColor()
VC.view .addSubview(lbl)


let txt = UITextField()
txt.frame =  CGRectMake(10, 35, 250, 30)
txt.borderStyle = UITextBorderStyle.RoundedRect
txt.placeholder = "enter text"
VC.view .addSubview(txt)


alert.setValue(VC, forKey: "contentViewController")

self.presentViewController(alert, animated: true, completion: nil)

从 Github 下载 Demo：https://github.com/nitingohel/NGAlertViewController-Swift2.0

Answer 3

试试这个代码：

UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"TEST" message:@"subview" delegate:nil cancelButtonTitle:@"NO" otherButtonTitles:@"YES", nil];
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 260, 55)];
[view addSubview:textField];
[view addSubview:charLeftLabel];
[alert setValue:view forKey:@"accessoryView"];
[alert show];

Answer 4

UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"TEST" message:@"subview" delegate:self cancelButtonTitle:@"NO" otherButtonTitles:@"YES", nil];
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 260, 55)];
[view addSubview:textField];
[view addSubview:charLeftLabel];
[alert setValue:view forKey:@"accessoryView"];
[alert show];