Question

我是新手，我正在尝试制作一个简单的温度转换应用程序。这里有错误被抛出：

2014-02-28 20:35:46.954 Temperature Converter[5899:70b] *** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<TemperatureConverterViewController 0x8a939a0> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key convertTemperatureButton.'
*** First throw call stack:
(
0   CoreFoundation                      0x017395e4 __exceptionPreprocess + 180
1   libobjc.A.dylib                     0x014bc8b6 objc_exception_throw + 44
2   CoreFoundation                      0x017c96a1 -[NSException raise] + 17
3   Foundation                          0x0117d9ee -[NSObject(NSKeyValueCoding) setValue:forUndefinedKey:] + 282
4   Foundation                          0x010e9cfb _NSSetUsingKeyValueSetter + 88
5   Foundation                          0x010e9253 -[NSObject(NSKeyValueCoding) setValue:forKey:] + 267
6   Foundation                          0x0114b70a -[NSObject(NSKeyValueCoding) setValue:forKeyPath:] + 412
7   UIKit                               0x004cca15 -[UIRuntimeOutletConnection connect] + 106
8   libobjc.A.dylib                     0x014ce7d2 -[NSObject performSelector:] + 62
9   CoreFoundation                      0x01734b6a -[NSArray makeObjectsPerformSelector:] + 314
10  UIKit                               0x004cb56e -[UINib instantiateWithOwner:options:] + 1417
11  UIKit                               0x0033d605 -[UIViewController _loadViewFromNibNamed:bundle:] + 280
12  UIKit                               0x0033ddad -[UIViewController loadView] + 302
13  UIKit                               0x0033e0ae -[UIViewController loadViewIfRequired] + 78
14  UIKit                               0x0033e5b4 -[UIViewController view] + 35
15  UIKit                               0x002669fd -[UIWindow addRootViewControllerViewIfPossible] + 66
16  UIKit                               0x00266d97 -[UIWindow _setHidden:forced:] + 312
17  UIKit                               0x0026702d -[UIWindow _orderFrontWithoutMakingKey] + 49
18  UIKit                               0x0027189a -[UIWindow makeKeyAndVisible] + 65
19  UIKit                               0x00224cd0 -[UIApplication _callInitializationDelegatesForURL:payload:suspended:] + 1851
20  UIKit                               0x002293a8 -[UIApplication _runWithURL:payload:launchOrientation:statusBarStyle:statusBarHidden:] + 824
21  UIKit                               0x0023d87c -[UIApplication handleEvent:withNewEvent:] + 3447
22  UIKit                               0x0023dde9 -[UIApplication sendEvent:] + 85
23  UIKit                               0x0022b025 _UIApplicationHandleEvent + 736
24  GraphicsServices                    0x036e02f6 _PurpleEventCallback + 776
25  GraphicsServices                    0x036dfe01 PurpleEventCallback + 46
26  CoreFoundation                      0x016b4d65 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 53
27  CoreFoundation                      0x016b4a9b __CFRunLoopDoSource1 + 523
28  CoreFoundation                      0x016df77c __CFRunLoopRun + 2156
29  CoreFoundation                      0x016deac3 CFRunLoopRunSpecific + 467
30  CoreFoundation                      0x016de8db CFRunLoopRunInMode + 123
31  UIKit                               0x00228add -[UIApplication _run] + 840
32  UIKit                               0x0022ad3b UIApplicationMain + 1225
33  Temperature Converter               0x00002eed main + 141
34  libdyld.dylib                       0x01d7770d start + 1
35  ???                                 0x00000001 0x0 + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException

现在，我知道我的按钮功能有问题所以这是我的界面和实现：

#import <UIKit/UIKit.h>

@interface TemperatureConverterViewController : UIViewController

@property (weak, nonatomic) IBOutlet UITextField *temperatureField;
@property (weak, nonatomic) IBOutlet UILabel *conversionResult;

- (IBAction)convertToFahrenheit:(id)sender;

@end

继承实施（.m文件）

#import "TemperatureConverterViewController.h"

@interface TemperatureConverterViewController ()

@end

@implementation TemperatureConverterViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (IBAction)convertToFahrenheit:(id)sender {
    double celsius = [_temperatureField.text doubleValue];
    double fahrenheit = (celsius+32)*1.8;
    NSString *result = [[NSString alloc] initWithFormat: @"Fahrenheit: %f",fahrenheit];
    _conversionResult.text = result;
}
@end

有人能找到这个问题吗？我不能:(

谢谢。

UPDATE !!!

当我按下虚拟设备中的文本字段时，键盘显示，但按下按钮时它不会消失！有谁知道我怎么解决这个问题？

非常感谢你！

Answer 1

检查XIB或Storyboard上的连接，确保所有内容都已正确连接。我打赌你联系了一个IBOutlet，你后来从你的界面中删除了仍然在文件所有者连接中闲逛的。

要解决第二个问题并解除键盘，请在IBAction中尝试以下操作：

[self.temperatureField resignFirstResponder];

Answer 2

您尚未在界面构建中将UIViewController的类设置为TemperatureConverterViewControllerclass。

设置课程将解决您的问题..至少为我做了

IOS app在测试启动时抛出错误

2 个答案: