我正在使用xcode 4.2和ARC。下面是我正在使用的代码。当我点击任何按钮时,我的应用程序都会崩溃,它会在main.m 中突出显示这段代码
有时我会得到这个错误
-[__NSCFTimer parentLogin:]: unrecognized selector sent to instance
有时应用程序崩溃而没有任何错误。
return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
我的代码是:
在我的ViewController.m中,我使用这段代码来访问ChooseLogin视图控制器。
- (IBAction)action:(id)sender {
ChooseLogin *loginScreen = [[ChooseLogin alloc] initWithNibName:@"ChooseLogin" bundle:nil];
[UIView beginAnimations:@"flipview" context:nil];
[UIView setAnimationDuration:2];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:self.view cache:NO];
[self.view addSubview:loginScreen.view];
[UIView commitAnimations];
}
然后在ChooseLogin.m:中
@implementation ChooseLogin
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad
{
[super viewDidLoad];
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}
- (IBAction)parentLogin:(id)sender {
NSLog(@":::::::");
NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
NSString *passwd = [prefs stringForKey:@"password"];
NSLog(@"data saved");
if (passwd == nil) {
CreatePassword *cPassword = [[CreatePassword alloc] initWithNibName:@"CreatePassword" bundle:nil ];
[UIView beginAnimations:@"flipview" context:nil];
[UIView setAnimationDuration:1];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:self.view cache:NO];
[self.view addSubview:cPassword.view];
[UIView commitAnimations];
}else {
UserPassword *uPasswd = [[UserPassword alloc] initWithNibName:@"UserPassword" bundle:nil];
[UIView beginAnimations:@"flipview" context:nil];
[UIView setAnimationDuration:1];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:self.view cache:NO];
[self.view addSubview:uPasswd.view];
[UIView commitAnimations];
}
}
- (IBAction)childLogin:(id)sender {
ChildLogin *loginScreen = [[ChildLogin alloc] initWithNibName:@"ChildLogin" bundle:nil];
[UIView beginAnimations:@"flipview" context:nil];
// [UIView setAnimationDuration:1];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:self.view cache:NO];
[self.view addSubview:loginScreen.view];
[UIView commitAnimations];
}
@end
-[__NSCFTimer parentLogin:]: unrecognized selector sent to instance
这意味着一条消息被发送到一个类无法识别的类——您可能没有编写这个自定义选择器(函数),或者某个函数被发送到错误的类,因此无法识别。XCode在编写代码时通常非常擅长捕捉这些信息,但它似乎不会在XIB文件中检查它们。
根据我的经验,这种类型的问题最常见的原因是当您删除或重命名一个函数,却忘记更新与该类相关的XIB文件时——或者您确实更新了它,它添加了该函数的新版本,而没有忘记旧版本。
- 您不应该将一个视图控制器的视图添加到另一个
- 如果你还想这么做。您创建控制器,获取它的视图,然后释放它,因为您将对它的引用存储在任何位置。使ivar
loginScreen
和ARC将为您保留ChooseLogin
控制器