ios - 代码不等待用户在重复密码部分完成输入

Question

我正在尝试使用 parse.com 作为后端来设置注册 View ，但出于某种原因，每当我开始在重新输入密码字段中输入内容时，只要我输入一些内容，它就会开始执行此操作

else if ([password compare:passwordAgain] != NSOrderedSame) {
        // We have non-zero strings.
        // Check for equal password strings.
            textError = YES;
            errorText = [errorText stringByAppendingString:passwordMismatchText];
            [_reEnterPasswordField becomeFirstResponder];
            NSLog(@"stops here");


    }

方法并向我发送错误消息 passwordMismatchText。每当我更改一个词时，无论是添加还是删除，它都会通过此消息。当我对 xib 使用相同的方法时，我没有遇到任何问题。但是在我尝试用 Storyboard做同样的事情之后，我遇到了这个问题。我尝试为 _doneButton.enabled == YES 创建一个用户默认值，并在 errorText =[...] 消息周围放置另一个 if ，但没有解决问题。感谢您的帮助。

注册 View Controller .h

#import <UIKit/UIKit.h>


@interface SignUpViewController : UIViewController<UITextFieldDelegate>
@property (weak, nonatomic) IBOutlet UIBarButtonItem *doneButton;
@property (weak, nonatomic) IBOutlet UITextField *userNameField;
@property (weak, nonatomic) IBOutlet UITextField *passwordField;
@property (weak, nonatomic) IBOutlet UITextField *reEnterPasswordField;
- (IBAction)done:(id)sender;
- (IBAction)cancel:(id)sender;

@end

SignUpViewController.m

#import "SignUpViewController.h"
#import <Parse/Parse.h>
#import "ActivityView.h"
#import "ProfileViewController.h"

@interface SignUpViewController ()
- (void)textInputChanged:(NSNotification *)note;
-(void)processFieldEntries;
- (BOOL)shouldEnableDoneButton;
@end

@implementation SignUpViewController

@synthesize doneButton = _doneButton;
@synthesize userNameField = _userNameField;
@synthesize passwordField = _passwordField;
@synthesize reEnterPasswordField = _reEnterPasswordField;


- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];

        [[NSNotificationCenter defaultCenter ]addObserver:self selector:@selector(textInputChanged:) name:  UITextFieldTextDidChangeNotification object:_userNameField];
        [[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(textInputChanged:) name:UITextFieldTextDidChangeNotification object:_passwordField];
        [[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(textInputChanged:) name:UITextFieldTextDidChangeNotification object:_reEnterPasswordField];

    _doneButton.enabled = NO;
    NSLog(@"nsnotification is working fine");

}
-(void)viewWillAppear:(BOOL)animated
{
    [_userNameField becomeFirstResponder];
    [super viewWillAppear:animated];
    NSLog(@"indeed usernamefield became a first responder");

}
- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}
-(BOOL)textFieldShouldReturn:(UITextField *)textField
{
    if (textField == _userNameField ) {
        [_userNameField becomeFirstResponder];
    }
    if (textField == _passwordField) {
        [_passwordField becomeFirstResponder];
    }
    if (textField == _reEnterPasswordField)
    {
        [_reEnterPasswordField becomeFirstResponder];
    }
    NSLog(@"keyboard action works fine ");
    return YES;
}
-(BOOL)shouldEnableDoneButton
{
    BOOL enableDoneButton = NO;

    if (_userNameField.text != nil &&
        _userNameField.text.length > 0 &&
        _passwordField.text != nil &&
        _passwordField.text.length > 0 &&
        _reEnterPasswordField.text != nil &&
        _reEnterPasswordField.text.length > 0)
    {
        [self processFieldEntries];
        enableDoneButton = YES;
        NSLog(@"done button enabled");
    }
    return enableDoneButton;

}
-(void)textInputChanged:(NSNotification *)note
{
    _doneButton.enabled = [self shouldEnableDoneButton];

}
- (IBAction)done:(id)sender {
    [_userNameField resignFirstResponder];
    [_passwordField resignFirstResponder];
    [_reEnterPasswordField resignFirstResponder];
    [self processFieldEntries];
    NSLog(@"do you see this");
}

- (IBAction)cancel:(id)sender
{
    [self.presentingViewController dismissViewControllerAnimated:YES completion:nil];

}
-(void)processFieldEntries
{
    // Check that we have a non-zero username and passwords.
    // Compare password and passwordAgain for equality
    // Throw up a dialog that tells them what they did wrong if they did it wrong.

    NSString *username = _userNameField.text;
    NSString *password = _passwordField.text;
    NSString *passwordAgain = _reEnterPasswordField.text;
    NSString *errorText = @"Please ";
    NSString *usernameBlankText = @"enter a username";
    NSString *passwordBlankText = @"enter a password";
    NSString *joinText = @", and ";
    NSString *passwordMismatchText = @"enter the same password twice";
    BOOL textError = NO;
    NSLog(@"validation begins here");

    // Messaging nil will return 0, so these checks implicitly check for nil text.
    if (username.length == 0 || password.length == 0 || passwordAgain.length == 0) {
        textError = YES;

        // Set up the keyboard for the first field missing input:
        if (passwordAgain.length == 0) {
            [_reEnterPasswordField becomeFirstResponder];
        }
        if (password.length == 0) {
            [_passwordField becomeFirstResponder];
        }
        if (username.length == 0) {
            [_userNameField becomeFirstResponder];
        }

        if (username.length == 0) {
            errorText = [errorText stringByAppendingString:usernameBlankText];
        }

        if (password.length == 0 || passwordAgain.length == 0) {
            if (username.length == 0) { // We need some joining text in the error:
                errorText = [errorText stringByAppendingString:joinText];
            }
            errorText = [errorText stringByAppendingString:passwordBlankText];
        }
    } else if ([password compare:passwordAgain] != NSOrderedSame) {
        // We have non-zero strings.
        // Check for equal password strings.
            textError = YES;
            errorText = [errorText stringByAppendingString:passwordMismatchText];
            [_reEnterPasswordField becomeFirstResponder];
            NSLog(@"stops here");


    }
    if (textError) {
        UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:errorText message:nil delegate:self cancelButtonTitle:nil otherButtonTitles:@"Ok", nil];
        [alertView show];
        return;
    }

    NSLog(@"validation works just fine");

    // Everything looks good; try to log in.
    // Disable the done button for now.
    _doneButton.enabled = NO;
    ActivityView *activityCircle = [[ActivityView alloc] initWithFrame:CGRectMake(0.f, 0.f, self.view.frame.size.width, self.view.frame.size.height)];
    UILabel *label = activityCircle.label;
    label.text = @"Signing You Up";
    label.font = [UIFont boldSystemFontOfSize:20.f];
    [activityCircle.activityIndicator startAnimating];
    [activityCircle layoutSubviews];

    [self.view addSubview:activityCircle];
    NSLog(@"activity view works just fine");

    //parse registeration
    // Call into an object somewhere that has code for setting up a user.
    // The app delegate cares about this, but so do a lot of other objects.
    // For now, do this inline.

    PFUser *user = [PFUser user];
    user.username = username;
    user.password = password;
    [user signUpInBackgroundWithBlock:^(BOOL succeeded, NSError *error) {
        if (error) {
            UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:[[error userInfo] objectForKey:@"error"] message:nil delegate:self cancelButtonTitle:nil otherButtonTitles:@"Ok", nil];
            [alertView show];
            _doneButton.enabled = [self shouldEnableDoneButton];
            [activityCircle.activityIndicator stopAnimating];
            [activityCircle removeFromSuperview];
            // Bring the keyboard back up, because they'll probably need to change something.
            [_userNameField becomeFirstResponder];
            return;
        }
        // Success!
        [activityCircle.activityIndicator stopAnimating];
        [activityCircle removeFromSuperview];
        //add the next screen here
    }];
    NSLog(@"user signedup just fine");
    //now pass the view from sign up to profile view
}
/*
 //this one didnt work
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{

    ProfileViewController *myProfileView = [segue destinationViewController];
    if (_doneButton.enabled == YES) {
           [myProfileView performSegueWithIdentifier:@"SignUpSegue" sender:_doneButton];
    }


}
 */
-(BOOL)shouldPerformSegueWithIdentifier:(NSString *)identifier sender:(id)sender
{
    NSLog(@"is this method visible");
    if (_doneButton.enabled == YES) {
        [self performSegueWithIdentifier:@"SignUpSegue" sender:_doneButton];
    }

return NO;

}

 @end

这是我得到的日志文件

2013-09-06 02:49:19.938  nsnotification is working fine
2013-09-06 02:49:19.942  indeed usernamefield became a first responder
2013-09-06 02:49:47.446  validation begins here
2013-09-06 02:49:47.448  stops here
2013-09-06 02:49:47.485  done button enabled
2013-09-06 02:49:49.271  validation begins here
2013-09-06 02:49:49.273  stops here
2013-09-06 02:49:49.296  done button enabled
2013-09-06 02:49:51.257  validation begins here
2013-09-06 02:49:51.259  validation works just fine
2013-09-06 02:49:51.265  activity view works just fine
2013-09-06 02:49:51.270  user signedup just fine
2013-09-06 02:49:51.271  done button enabled

Answer 1

您正在通过观察 UITextFieldTextDidChangeNotification 来触发代码运行。当这通过您的方法移动时，您最终会调用 processFieldEntries。可能您不应该从 shouldEnableDoneButton 调用 processFieldEntries。