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iOS 8.3 UIAlertController crashes when trying to add a textfield

由 穿精又带淫゛_ 提交于 2019-11-30 06:40:50

Edit: This fix changes depending on if you are building with Xcode 6 or Xcode 7, so I've added the relevant information for both versions of Xcode.

I ran into this today and what it's saying is that it can't add the text field to the view controller's view or that it can't add auto-layout constraints to its superview. This seems to be because it hasn't created the superview to add it to yet, and so it all panics and crashes.

Simple fix I found is add the text field after you tell the alert controller to present. That fixed it to me, though I'm not sure if it'll affect anything like the text field popping in as the alert is presenting.

Built with Xcode 6

let alertController = UIAlertController(title: "Enter Name", message:nil, preferredStyle: .Alert)

let okAction = UIAlertAction(title: "Ok", style: .Default) { (_) -> Void in
    // Some action here
}
alertController.addAction(okAction)

presentViewController(alertController, animated: true, completion: nil)

// Add any text fields after presenting the alert controller to fix crash in iOS 8.3
alertController.addTextFieldWithConfigurationHandler { (textfield) -> Void in
    textfield.placeholder = "Name"
}

P.s. As a side note from your code example, remember with Swift, you don't need to use ; at the end of every line, though it doesn't matter if you do. 😉

Built with Xcode 7

When you build your app using Xcode 7, it seems like Apple have fixed the issue. Using the method shown above will no longer show a text field in iOS 9 (even though it still shows correctly in iOS 8).

Below is a snippet of code, how it should have been the whole time, and when built in Xcode 7 it runs correctly in iOS 8 and iOS 9.

let alertController = UIAlertController(title: "Enter Name", message:nil, preferredStyle: .Alert)

alertController.addTextFieldWithConfigurationHandler { (textfield) -> Void in
    textfield.placeholder = "Name"
}

let okAction = UIAlertAction(title: "Ok", style: .Default) { (_) -> Void in
    // Some action here
}
alertController.addAction(okAction)

presentViewController(alertController, animated: true, completion: nil)

Tested in Swift 2.0 and Obj-C with Xcode 7 GM (7A218)

This bug is triggered if the UIAlertController's view is loaded when you calling -addTextFieldWithConfigurationHandler: ([alert isViewLoaded] == YES).

If you are accessing alert.view prior to calling -addTextFieldWithConfigurationHandler, move whatever you are doing with alert.view to after the call to -addTextFieldWithConfigurationHandler:.

As @Dex mentioned, I fixed this by modifying my controller's view AFTER adding the text field. I was modifying the view's tint color.

controller.view.tintColor = ...some color...

Moving this to "after" adding the text field fixed it for me. Accepted answer and other suggestions led to other bugs for me. Sorry, I don't have the rep to post a comment yet on @Dex's answer.

This seems to have something to do with styling the UIAlertController's view, as eluded to by @BigShay.

In my example I set the tintColor of the view before adding the UITextField and I crash in iOS 8. The workaround given by @Baza207 to add the UITextField after displaying the alert avoids the crash in iOS 8, however it also results in no text field appearing at all in iOS 9.

If you just move the styling to after adding the text field, it works with both iOS 8 and iOS 9 (no crash in iOS 8, and no missing text field in iOS 9):

Crash in iOS 8

Works in iOS 9

alertController.view.tintColor = UIColor.blueColor()

alertController.addTextFieldWithConfigurationHandler { textField in
}

presentViewController(alertController, animated: true, completion: nil)

Works in iOS 8

No text text field in iOS 9

alertController.view.tintColor = UIColor.blueColor()

presentViewController(alertController, animated: true, completion: nil)

alertController.addTextFieldWithConfigurationHandler { textField in
}

Works in iOS 8

Works in iOS 9

alertController.addTextFieldWithConfigurationHandler { textField in
}

alertController.view.tintColor = UIColor.blueColor()

presentViewController(alertController, animated: true, completion: nil)

There does seem to a bug in iOS 8.3 related alerts. It manifests on both (deprecated) UIAlertView and the iOS8-only UIAlertController. When I attempt to add a textfield to either of these controllers, I get the following crash:

 *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'The layout constraints still need update after sending -updateConstraints to <_UIKeyboardLayoutAlignmentView: 0x792d28e0; frame = (0 0; 0 0); userInteractionEnabled = NO; layer = <CALayer: 0x792d2ab0>>.
_UIKeyboardLayoutAlignmentView or one of its superclasses may have overridden -updateConstraints without calling super. Or, something may have dirtied layout constraints in the middle of updating them.  Both are programming errors.'

Alerts without textfields are OK, but showing a UIAlertView with style UIAlertViewStylePlainTextInput or showing a UIAlertController with a textfield added via addTextFieldWithConfigurationHandler will result in the above crash.

The fix seems to be to set a prophylactic frame on the UIAlertController before calling show. This frame is overridden before show, but prevents the crash.

if (NSClassFromString(@"UIAlertController")) {
    // iOS8
    UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"Alert"
                                                                   message:@"Be alert, not alarmed"
                                                            preferredStyle:UIAlertControllerStyleAlert];
    [alert addTextFieldWithConfigurationHandler:^(UITextField *textField) {
        textField.keyboardType = UIKeyboardTypeEmailAddress;

    }];
    alert.view.frame = CGRectMake(0.0, 0.0, 320.0, 400.0); // Workaround iOS8.3 bug - set this to larger than you'll need

    [self presentViewController:alert animated:YES completion:^{
        [alert.textFields[0] becomeFirstResponder];
    }];
} else {
    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Alert"
                                                    message:@"Be alert, not alarmed"
                                                   delegate:nil
                                          cancelButtonTitle:@"OK"
                                          otherButtonTitles:nil];
    alert.alertViewStyle = UIAlertViewStylePlainTextInput;
    UITextField *emailField = [alert textFieldAtIndex:0];
    emailField.keyboardType = UIKeyboardTypeEmailAddress;

    [alert show];
}

I just ran your code inside my test project — everything worked fine on 8.3.

View not found in container hierarchy:

This error usually appears if you mess up UIViewController child/parent relationship. There are few points to consider:

  • the controller you are using to present alert is topmost and is not presenting anything else already
  • parent controllers either have the one you use as a child (addChildViewController:) or are in a state of presenting it through either presentViewController:animated:completion: or the likes of it
  • controller's view is loaded before presenting another ViewController

Also, there is definitely something wrong with the frames.

Chris

I had a similair problem that is also mentioned in the comments. Please see this if you are getting.

*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'The layout constraints still need update after sending -updateConstraints to <_UIKeyboardLayoutAlignmentView: 0x792d28e0; frame = (0 0; 0 0); userInteractionEnabled = NO; layer = >. _UIKeyboardLayoutAlignmentView or one of its superclasses may have overridden -updateConstraints without calling super. Or, something may have dirtied layout constraints in the middle of updating them. Both are programming errors.'

NSInteralInconsistencyException - UIKeyboardLayoutAlignmentView

Try to set alert.view.frame explicitly to something small. I think by default it may be as big as the application view, triggering this on its subviews.

I have the same problem with the new iOS 8.3 and Swift 1.2. UIAlertController in UIViewController with nested UITableView does not work as in start topic.

So, I made a real modal form.

  1. Create new UIViewController width, set views background to black with 0.4 opacity
  2. Add a 300x150 UIView with two buttons, label and UITextField
  3. Add constraints and other needed staff

  4. Connect modally other controllers with the new one

  5. And specify special class for new controller as "PopupWindow". Then create this class:

    import UIKit

class PopupWindow: UIViewController, UITextFieldDelegate {

    @IBOutlet var wrapper: UIView!
    @IBOutlet var btnCancel: UIButton!
    @IBOutlet var btnSave: UIButton!
    @IBOutlet var textField: UITextField!
    @IBOutlet var labelField: UILabel!

    var keyboardHeight: CGFloat = 0
    var data = [:]
    var closure: ((textField: UITextField!) -> Void)?
    var tmpText = ""

    override func viewDidLoad() {
        super.viewDidLoad()

        self.labelField.text = self.data["title"] as? String
        self.textField.text = self.data["text"] as? String

        self.btnCancel.setTitle("cancel", forState: UIControlState.Normal)
        var tmp = self.data["save"] != nil
            ? self.data["save"] as! String
            : "save"
        self.btnSave.setTitle(tmp, forState: UIControlState.Normal)
        self.btnSave.enabled = false

        self.wrapper.layer.cornerRadius = 5.0 as CGFloat
        self.textField.becomeFirstResponder()
    }

    @IBAction func onBtnCancel() {
        self.dismissViewControllerAnimated(true, completion: nil)
    }

    @IBAction func onBtnSave() {
        if self.closure != nil {
            self.dismissViewControllerAnimated(true, completion: {
                _ in
                self.closure!(textField: self.textField)
            })
        }

    }

    override func didRotateFromInterfaceOrientation(fromInterfaceOrientation: UIInterfaceOrientation) {
        self.fixTopOffset()
    }

    override func viewWillAppear(animated: Bool) {
        super.viewWillAppear(animated)

        NSNotificationCenter.defaultCenter().addObserver(self, selector: "textFieldDidChange:", name: UITextFieldTextDidChangeNotification, object: self.textField)

        NSNotificationCenter.defaultCenter().addObserver(self, selector: "onKeyboadWillShow:", name: UIKeyboardWillShowNotification, object: nil)
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "onKeyboadWillShow:", name: UIKeyboardWillChangeFrameNotification, object: nil)
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "onKeyboardWillHide:", name: UIKeyboardWillHideNotification, object: nil)
    }

    override func viewWillDisappear(animated: Bool) {
        super.viewWillDisappear(animated)

        NSNotificationCenter.defaultCenter().removeObserver(self, name: UITextFieldTextDidChangeNotification, object: nil)

        NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillShowNotification, object: nil)
        NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillChangeFrameNotification, object: nil)
        NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
    }

    func onKeyboadWillShow(notification: NSNotification) {
        self.fixTopOffset()
        let info: NSDictionary = notification.userInfo!
        if let rectValue = info[UIKeyboardFrameBeginUserInfoKey] as? NSValue {
            let kbSize: CGRect = rectValue.CGRectValue()
            if self.keyboardHeight != kbSize.size.height {
                self.keyboardHeight = kbSize.size.height
                self.fixTopOffset()
            }
        }
    }

    func onKeyboardWillHide(notification: NSNotification) {
        self.fixTopOffset()
        if self.keyboardHeight != 0 {
            self.keyboardHeight = 0
            self.fixTopOffset()
        }
    }

    func fixTopOffset(landscape: Bool = true) {
        let height1: CGFloat = self.view.frame.height / 2
        let height2: CGFloat = height1 - self.keyboardHeight / 2
        let margin: CGFloat = height1 - height2
        for tmp in self.view.constraints() {
            if let constraint = tmp as? NSLayoutConstraint {
                if constraint.firstAttribute == NSLayoutAttribute.CenterY {
                    if constraint.constant != margin {
                        constraint.constant = margin
                    }
                }
            }

        }
    }

    func textFieldDidChange(notification: NSNotification) {
        if notification.object != nil {
            if let textField = notification.object as? UITextField {
                self.btnSave.enabled = textField.text != self.tmpText
            }
        }
    }

}

You need to connect all IBOutlets with corresponding elements in view by Ctrl+Drag.

  1. And now you can use it window in any connected controller. For example:

    import UIKit

class ExampleView: UIViewController {

    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {       
        if segue.identifier == "showPopup" {
            if let controller = segue.destinationViewController as? PopupWindow {
                controller.data = sender as! NSDictionary
                // This action will be called after form submission
                // We just print text in console
                controller.closure = {
                    (textField: UITextField!) in
                    println(textField)
                }
            }
        }
    }

    func showPopupWindow() {
        let data = [
                "title": "My Window",
                "save": "Save",
                "text": "Do you realy want to save this text?",
        ]
        self.performSegueWithIdentifier("showPopup", sender: data)
    }
}

Now I can just add a segue to controller and write any closure in prepareSegue method - and it works!

I made short video with popup window in my app - http://youtu.be/JmqAAeUN-XU

chrbal

Aha, I think this may be answered by jcesarmobile in another thread: UIAlertController/UIAlertView scrolling on iOS 8

The workaround a lot of folks added to deal with prior bugs with long text in UIAlertController now causes this crash in 8.3. And the long text issue is fixed in 8.3, so the workaround can be made conditional to avoid this in 8.3

Michael

This fixed it immediately (for me). I had the exact same error that Chris described :

NSInteralInconsistencyException - UIKeyboardLayoutAlignmentView

The answer was simply to make sure animated is set to "NO" when presenting the UIAlertController.

[self presentViewController:alert animated:NO completion:nil];

I really didn't like the solutions I saw and came up with an easier one. The crash occurs (for me, at least) when the keyboard is visible and an alert with an input field is presented.

I simply dismiss the keyboard prior to presenting the alert and then everything is fine.

标签
ios
crash
uialertcontroller
ios8.3
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