ios - UIAlertController 在几分之一秒内关闭

Question

我正在实现 UIAlertController，如下所示:

-(void)createAlert{

    UIAlertController * alert=   [UIAlertController
                                  alertControllerWithTitle:@"Ошибка электронного адреса"
                                  message:@"Ваш электронный адрес должен содержать символ @ и название домена"
                                  preferredStyle:UIAlertControllerStyleAlert];

    UIAlertAction* yesButton = [UIAlertAction
                                actionWithTitle:@"Сейчас исправлю"
                                style:UIAlertActionStyleDefault
                                handler:^(UIAlertAction * action)
                                {
                                    //Handel your yes please button action here
                                    [alert dismissViewControllerAnimated:YES completion:nil];

                                }];


    [alert addAction:yesButton];


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

但是，它仅显示一小部分秒(大约 0.5 秒)的警报。我该如何解决这个问题，以便只有在用户按下"is"按钮后它才会消失？

更新 - 有完整的实现代码需要:

#define RGB(r, g, b) \
[UIColor colorWithRed:(r)/255.0 green:(g)/255.0 blue:(b)/255.0 alpha:1]
#define RGBA(r, g, b, a) \
[UIColor colorWithRed:(r)/255.0 green:(g)/255.0 blue:(b)/255.0 alpha:(a)]

//cell.textColor = RGB(0x66, 0x33, 0x33);

@interface ViewController ()

@property (weak, nonatomic) IBOutlet UILabel *enterLoginLabel;
@property (weak, nonatomic) IBOutlet UILabel *enterEmailTextLabel;
@property (weak, nonatomic) IBOutlet UILabel *confirmEmailTextLabel;

@property (weak, nonatomic) IBOutlet UIButton *maleButton;
@property (weak, nonatomic) IBOutlet UIButton *femaleButton;

@property (weak, nonatomic) IBOutlet UITextField *loginTextField;
@property (weak, nonatomic) IBOutlet UITextField *emailTextField;
@property (weak, nonatomic) IBOutlet UITextField *emailConfirmTextField;




@end

@implementation ViewController {

    BOOL isMale;
    BOOL isFemale;
    BOOL isStartTyping;
    BOOL loginIsMoved;
    BOOL emailIsMoved;
    BOOL emailConfirmIsMoved;
    int currentIndex;


}

- (void)viewDidLoad {

    [super viewDidLoad];

    [self setColors];
    [self addTargets];

}


#pragma mark - gender check


- (IBAction)maleButtonTapped:(id)sender {

    if (!isMale && !isFemale){

        [UIView animateWithDuration:2.0 animations:^{
            self.maleButton.backgroundColor = RGB(0x63, 0xB8, 0xFF);
        } completion:NULL];

        isMale = YES;

    }

    if (isFemale && !isMale){

        [UIView animateWithDuration:2.0 animations:^{
            self.femaleButton.backgroundColor = RGB(0xC1, 0xCD, 0xCD);
        } completion:NULL];

        isFemale = NO;

        [UIView animateWithDuration:2.0 animations:^{
            self.maleButton.backgroundColor = RGB(0x63, 0xB8, 0xFF);
        } completion:NULL];

        isMale = YES;
    }

}

- (IBAction)femaleButtonTapped:(id)sender {


    if (!isMale && !isFemale){

        [UIView animateWithDuration:2.0 animations:^{
            self.femaleButton.backgroundColor = RGB(0xFF, 0x83, 0xFA);
        } completion:NULL];

        isFemale = YES;
    }

    if (isMale && !isFemale){

        [UIView animateWithDuration:2.0 animations:^{
            self.maleButton.backgroundColor = RGB(0xC1, 0xCD, 0xCD);
        } completion:NULL];

        isMale = NO;

        [UIView animateWithDuration:2.0 animations:^{
            self.femaleButton.backgroundColor = RGB(0xFF, 0x83, 0xFA);
        } completion:NULL];

        isFemale = YES;

    }

}


#pragma mark - color

-(void)setColors{

    self.view.backgroundColor = RGB(0xF0, 0xE6, 0x8c);
    self.maleButton.backgroundColor = RGB(0xC1, 0xCD, 0xCD);
    self.femaleButton.backgroundColor = RGB(0xC1, 0xCD, 0xCD);
}

#pragma mark - UITextFieldDelegate

-(void)textFieldDidBeginEditing:(UITextField *)textField
{



    if (textField == self.loginTextField){
        NSLog(@"login  text field");
        currentIndex = 1;
    }

    if (textField == self.emailTextField){
        NSLog(@"Email text field");
        currentIndex = 2;
    }

    if (textField == self.emailConfirmTextField){
        NSLog(@"Confirm email text field");
        currentIndex = 3;
    }

    NSLog(@"begin");
}

-(void)textFieldDidEndEditing:(UITextField *)textField
{


    if ([textField.text length] >0){

        [self labelWithIndex:currentIndex].hidden = YES;
    }

    NSLog(@"End edit");
    [self dismissViewControllerAnimated:YES completion:nil];
}


-(BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string{

    return YES;
}

-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
    NSLog(@"touchesBegan:withEvent:");
    [self.view endEditing:YES];
    [super touchesBegan:touches withEvent:event];


}

- (BOOL)textFieldShouldReturn:(UITextField *)textField
{

    if (textField == self.emailTextField){

    if ([self NSStringIsValidEmail:textField.text]){

        [self animateWithTextField:textField];

    }   else {

        [self createAlert];
    }

    }


    return YES;
}

#pragma mark - animation and frame

-(CGRect)rectWithLabe:(UILabel*)label{

    CGRect newRect = label.frame;
    newRect.origin.y = newRect.origin.y - 25;
    newRect.size.width =  newRect.size.width + 100;

    return newRect;
}

-(void)addTargets{

    [self.loginTextField addTarget:self
                            action:@selector(textFieldDidChange:)
                  forControlEvents:UIControlEventEditingChanged];

    [self.emailTextField addTarget:self
                            action:@selector(textFieldDidChange:)
                  forControlEvents:UIControlEventEditingChanged];

    [self.emailConfirmTextField addTarget:self
                                   action:@selector(textFieldDidChange:)
                         forControlEvents:UIControlEventEditingChanged];

}

-(CGRect)finalRectForLabelWithTextField:(UITextField*)textField{

    CGRect frameRect = textField.frame;
    frameRect.origin.x = 50;
    return frameRect;
}



-(void) textFieldDidChange:(UITextField *)textField
{

    // Logic for login text field

    if([textField.text length]>0){

        if (currentIndex == 1 && !loginIsMoved){

            NSLog(@"Current index is 1");
            [self animateWithLabel:self.enterLoginLabel andRect:[self rectWithLabe:[self enterLoginLabel]]];
            loginIsMoved = YES;

        }



    } else {

        if (currentIndex == 1){
            // self.rect = self.labelPlaceHolder.frame;
            [self animateWithLabel:self.enterLoginLabel andRect:[self finalRectForLabelWithTextField:textField]];

        }

        loginIsMoved = NO;
    }

    // Logic for email text field

    if([textField.text length]>0){

        if (currentIndex == 2 && !emailIsMoved){

            NSLog(@"Current index is 1");
            [self animateWithLabel:self.enterEmailTextLabel andRect:[self rectWithLabe:[self enterEmailTextLabel]]];
            emailIsMoved = YES;

        }



    } else {

        if (currentIndex == 2){
            // self.rect = self.labelPlaceHolder.frame;
            [self animateWithLabel:self.enterEmailTextLabel andRect:[self finalRectForLabelWithTextField:textField]];

        }

        emailIsMoved = NO;
    }

    // Logic for confirm email text field

    if([textField.text length]>0){

        if (currentIndex == 3 && !emailConfirmIsMoved){

            NSLog(@"Current index is 1");
            [self animateWithLabel:self.confirmEmailTextLabel  andRect:[self rectWithLabe:[self confirmEmailTextLabel ]]];
            emailConfirmIsMoved = YES;

        }



    } else {

        if (currentIndex == 3){
            // self.rect = self.labelPlaceHolder.frame;
            [self animateWithLabel:self.confirmEmailTextLabel andRect:[self finalRectForLabelWithTextField:textField]];

        }

        emailConfirmIsMoved = NO;
    }
}


-(void)createCircle{

    UIView *circleView;

    circleView = [[UIView alloc] initWithFrame:CGRectMake(100,100,20,20)];
    circleView.alpha = 0.5;
    circleView.layer.cornerRadius = 10;
    circleView.backgroundColor = RGB(0x00, 0xC7, 0x8c);

    [self.view addSubview:circleView];
}

-(void)animateWithLabel:(UILabel*)label andRect:(CGRect)rect{

    [UIView animateWithDuration:0.3 delay:0 usingSpringWithDamping:0.7 initialSpringVelocity:0.3 options:0 animations:^{

        label.frame = rect;

    } completion:^(BOOL finished) {

    }];


}

-(void)animateWithTextField:(UITextField*)textField{

    UIView *circleView;

    circleView = [[UIView alloc] initWithFrame:CGRectMake(textField.frame.origin.x, textField.frame.origin.y, 20, 20)];
    circleView.alpha = 0.5;
    circleView.layer.cornerRadius = 10;
    circleView.backgroundColor = RGB(0x00, 0xC7, 0x8c);
    circleView.hidden = YES;

    [self.view addSubview:circleView];


    [UIView animateWithDuration:1.5 delay:0 usingSpringWithDamping:0.7 initialSpringVelocity:0.3 options:0 animations:^{

        circleView.hidden = NO;
        CGRect newRect = textField.frame;
        newRect.origin.y = newRect.origin.y - 25;
        newRect.size.width =  newRect.size.width + 100;

        circleView.frame = CGRectMake(newRect.origin.x, newRect.origin.y, 20, 20);
        [self labelWithIndex:2].hidden = YES;


    } completion:^(BOOL finished) {

    }];

}



#pragma mark - helper methods

-(void)createAlert{

    UIAlertController * alert=   [UIAlertController
                                  alertControllerWithTitle:@"Ошибка электронного адреса"
                                  message:@"Ваш электронный адрес должен содержать символ @ и название домена"
                                  preferredStyle:UIAlertControllerStyleAlert];

    UIAlertAction* yesButton = [UIAlertAction
                                actionWithTitle:@"Сейчас исправлю"
                                style:UIAlertActionStyleDefault
                                handler:^(UIAlertAction * action)
                                {
                                    //Handel your yes please button action here
                                    [alert dismissViewControllerAnimated:YES completion:nil];

                                }];


    [alert addAction:yesButton];


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

-(UILabel*)labelWithIndex:(int)myIndex{

    UILabel *correctLabel;

    if (myIndex == 1){
        correctLabel = self.enterLoginLabel;
    }

    if (myIndex == 2){
        correctLabel = self.enterEmailTextLabel;
    }

    if (myIndex == 3){
        correctLabel = self.confirmEmailTextLabel;
    }

    return correctLabel;

}





-(BOOL) NSStringIsValidEmail:(NSString *)checkString
{
    BOOL stricterFilter = NO;
    NSString *stricterFilterString = @"^[A-Z0-9a-z\\._%+-]+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2,4}$";
    NSString *laxString = @"^.+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2}[A-Za-z]*$";
    NSString *emailRegex = stricterFilter ? stricterFilterString : laxString;
    NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex];
    return [emailTest evaluateWithObject:checkString];
}

Answer 1

删除 textFieldDidEndEditing 中的 dismissViewControllerAnimated:YES 行，然后重试。

textFieldDidEndEditing，将在文本字段文本更改完成后调用。

来自文档:

Tells the delegate that editing stopped for the specified text field.

因此，即使您在文本字段委托(delegate)方法中显示警报，它也会很快被取消，因为其他文本字段委托(delegate)方法将被命中。