創建了導航條的自定義按鈕,點擊時,會中止:
-(void)viewDidLoad
{
UIImage *backButtonImage = [UIImage imageNamed:@"button.png"];
UIButton *backButton = [UIButton buttonWithType:UIButtonTypeCustom];
[backButton setImage:backButtonImage forState:UIControlStateNormal];
backButton.frame = CGRectMake(0, 0, backButtonImage.size.width, backButtonImage.size.height);
[backButton addTarget:self action:@selector(back) forControlEvents:UIControlEventTouchUpInside];
UIBarButtonItem *customBackBarItem = [[UIBarButtonItem alloc] initWithCustomView:backButton];
self.navigationItem.leftBarButtonItem = customBackBarItem;
}
-(void)goBackOne
{
[self.navigationController popToRootViewControllerAnimated:YES];
}
輸出:
2013-07-28 15:00:37.932 Habit Pal[1562:c07] -[SleepModeViewController back]: unrecognized selector sent to instance 0x9167300
2013-07-28 15:00:37.932 Habit Pal[1562:c07] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[SleepModeViewController back]: unrecognized selector sent to instance 0x9167300'
*** First throw call stack:
(0x1c93012 0x10d0e7e 0x1d1e4bd 0x1c82bbc 0x1c8294e 0x10e4705 0x182c0 0x18258 0xd9021 0xd957f 0xd86e8 0x47cef 0x47f02 0x25d4a 0x17698 0x1beedf9 0x1beead0 0x1c08bf5 0x1c08962 0x1c39bb6 0x1c38f44 0x1c38e1b 0x1bed7e3 0x1bed668 0x14ffc 0x213d 0x2065)
libc++abi.dylib: terminate called throwing an exception
(lldb)
你的按鈕是在SleepModeViewController試圖使用選擇器back
,而實際上你給方法命名為-goBackOne
。你應該重命名-goBackOne
方法為-back
,或者將選擇器的名字改為goBackOne
。舉例:
// The selector must actually match a method name on the target
[backButton addTarget:self action:@selector(goBackOne) forControlEvents:UIControlEventTouchUpInside];
選擇器和方法命名匹配非常重要。錯誤是提示你沒有名為-back的選擇器。