Question

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我正在使用导航控制器，其结构如下图所示。当用户在SigupViewController上并且成功时，我调用

[self.navigationController popToRootViewControllerAnimated:YES];

这会导致以下错误。如果我删除此行，我不会收到错误。奇怪的是，我在LoginViewController（之前的那一行）中有相同的行，当它被调用时，它按预期执行而没有错误。关于我应该修复什么的任何建议？

错误：

2014-03-05 06:39:49.240 Walk With Me[2035:70b] worked
2014-03-05 06:39:49.245 Walk With Me[2035:70b] -[SigupViewController signup:]: unrecognized selector sent to instance 0xa5599b0
2014-03-05 06:39:49.249 Walk With Me[2035:70b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[SigupViewController signup:]: unrecognized selector sent to instance 0xa5599b0'
*** First throw call stack:
(
 0   CoreFoundation                      0x038635e4 __exceptionPreprocess + 180
 1   libobjc.A.dylib                     0x035e68b6 objc_exception_throw + 44
 2   CoreFoundation                      0x03900903 -[NSObject(NSObject) doesNotRecognizeSelector:] + 275
 3   CoreFoundation                      0x0385390b ___forwarding___ + 1019
 4   CoreFoundation                      0x038534ee _CF_forwarding_prep_0 + 14
 5   libobjc.A.dylib                     0x035f881f -[NSObject performSelector:withObject:] + 70
 6   UIKit                               0x023560c2 -[UIApplication sendAction:to:from:forEvent:] + 108
 7   UIKit                               0x0235604e -[UIApplication sendAction:toTarget:fromSender:forEvent:] + 61
 8   UIKit                               0x0244e0c1 -[UIControl sendAction:to:forEvent:] + 66
 9   UIKit                               0x0244e484 -[UIControl _sendActionsForEvents:withEvent:] + 577
 10  UIKit                               0x02a32853 -[UITextField _resignFirstResponder] + 300
 11  UIKit                               0x024ae08e -[UIResponder _finishResignFirstResponder] + 181
 12  UIKit                               0x024ae1b6 -[UIResponder resignFirstResponder] + 288
 13  UIKit                               0x02a325f4 -[UITextField resignFirstResponder] + 118
 14  UIKit                               0x023af044 -[UIView(Hierarchy) _removeFirstResponderFromSubtree] + 205
 15  UIKit                               0x023af366 __UIViewWillBeRemovedFromSuperview + 71
 16  UIKit                               0x023af238 -[UIView(Hierarchy) removeFromSuperview] + 70
 17  UIKit                               0x0267a6a3 -[UINavigationTransitionView _cleanupTransition] + 103
 18  UIKit                               0x0267a93a -[UINavigationTransitionView _navigationTransitionDidStop] + 55
 19  UIKit                               0x023a0c6c -[UIViewAnimationState sendDelegateAnimationDidStop:finished:] + 267
 20  UIKit                               0x0239f455 +[UIViewAnimationState popAnimationState] + 334
 21  UIKit                               0x023b3cf6 +[UIView(Animation) commitAnimations] + 36
 22  UIKit                               0x0267a3f9 -[UINavigationTransitionView transition:fromView:toView:] + 2795
 23  UIKit                               0x02679906 -[UINavigationTransitionView transition:toView:] + 55
 24  UIKit                               0x0248ed47 -[UINavigationController _startTransition:fromViewController:toViewController:] + 3186
 25  UIKit                               0x0248f09c -[UINavigationController _startDeferredTransitionIfNeeded:] + 645
 26  UIKit                               0x0248fcb9 -[UINavigationController __viewWillLayoutSubviews] + 57
 27  UIKit                               0x025c9181 -[UILayoutContainerView layoutSubviews] + 213
 28  UIKit                               0x023bf267 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 355
 29  libobjc.A.dylib                     0x035f881f -[NSObject performSelector:withObject:] + 70
 30  QuartzCore                          0x0222e2ea -[CALayer layoutSublayers] + 148
 31  QuartzCore                          0x022220d4 _ZN2CA5Layer16layout_if_neededEPNS_11TransactionE + 380
 32  QuartzCore                          0x02221f40 _ZN2CA5Layer28layout_and_display_if_neededEPNS_11TransactionE + 26
 33  QuartzCore                          0x02189ae6 _ZN2CA7Context18commit_transactionEPNS_11TransactionE + 294
 34  QuartzCore                          0x0218ae71 _ZN2CA11Transaction6commitEv + 393
 35  QuartzCore                          0x0218b544 _ZN2CA11Transaction17observer_callbackEP19__CFRunLoopObservermPv + 92
 36  CoreFoundation                      0x0382b4ce __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 30
 37  CoreFoundation                      0x0382b41f __CFRunLoopDoObservers + 399
 38  CoreFoundation                      0x03809344 __CFRunLoopRun + 1076
 39  CoreFoundation                      0x03808ac3 CFRunLoopRunSpecific + 467
 40  CoreFoundation                      0x038088db CFRunLoopRunInMode + 123
 41  GraphicsServices                    0x045be9e2 GSEventRunModal + 192
 42  GraphicsServices                    0x045be809 GSEventRun + 104
 43  UIKit                               0x02354d3b UIApplicationMain + 1225
 44  Walk With Me                        0x00005bbd main + 141
 45  libdyld.dylib                       0x03da470d start + 1
 46  ???                                 0x00000001 0x0 + 1
 )
libc++abi.dylib: terminating with uncaught exception of type NSException

代码：

    PFUser *user = [PFUser user];
    user.username = username;
    user.password = password;
    user.email = email;

    [user signUpInBackgroundWithBlock:^(BOOL succeeded, NSError *error) {
        if (!error) {
            NSLog(@"worked");
            [self.navigationController popToRootViewControllerAnimated:YES];

        }
        else {
            UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Sorry!" message:[error.userInfo objectForKey:@"error"] delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
            [alertView show];
        }
    }];

SigUpViewController.h：

#import <UIKit/UIKit.h>

@interface SigupViewController : UIViewController
@property (weak, nonatomic) IBOutlet UITextField *usernameField;
@property (weak, nonatomic) IBOutlet UITextField *passwordField;
@property (weak, nonatomic) IBOutlet UITextField *emailField;


- (IBAction)signingU:(id)sender;

@end

Answer 1

您正在致电

[SigupViewController signup:]:

但是SigupViewController类中没有使用该签名的方法。我假设你已经把它与IB联系起来所以添加：

- (IBAction) signup:(id) sender;

在SigupViewController.h

中

如果是错误，也可以删除对此方法的调用。

如何使用popToRootViewController修复错误？

1 个答案: