由于未捕获的异常“NSUnknownKeyException"而终止应用程序:iOS 应用程序崩溃 [英] Terminating app due to uncaught exception 'NSUnknownKeyException' : iOS app crash
问题描述
我是一名开发 iPhone 应用程序的初级程序员.我想知道是否有人可以帮助我解决我的应用程序中的错误.在 XCode 上编程时，我发现在添加更多代码后，我的应用程序在启动时突然崩溃.输出面板显示以下错误:
<块引用>* 由于未捕获的异常NSUnknownKeyException"而终止应用程序，原因:[setValue:forUndefinedKey:]:该类不是键值编码兼容的键播放."* 先抛出调用栈:(0x1c91012 0x10cee7e 0x1d19fb1 0xb7ae41 0xafc5f8 0xafc0e7 0xb26b58 0x230019 0x10e2663 0x1c8c45a 0x22eb1c 0xf37e7 0xf3dc8 0xf3ff8 0xf4232 0x433d5 0x4376f 0x43905 0x8eceab6 0x4c917 0x1096c 0x1194b 0x22cb5 0x23beb 0x15698 0x1becdf9 0x1becad0 0x1c06bf5 0x1c06962 0x1c37bb6 0x1c36f44 0x1c36e1b 0x1117a 0x12ffc 0x222d 0x2155)libc++abi.dylib:终止调用抛出异常(lldb)
应用程序终止时显示的代码如下
#import #import "CIAAppDelegate.h"int main(int argc, char *argv[]){@autoreleasepool {返回 UIApplicationMain(argc, argv, nil, NSStringFromClass([CIAAppDelegate class]));}} 我的 ViewController.h 显示:
#import @interface CIAViewController : UIViewController {IBOutlet UILabel *cruzia;IBOutlet UILabel *textarea;IBOutlet UIButton *playbtn;IBOutlet UIButton *tutorialbtn;IBOutlet UIButton *optionsbtn;IBOutlet UIButton *trainingbtn;IBOutlet UIButton *back;}-(IBAction)按下；-(IBAction)press2;-(IBAction)press3;-(IBAction)press4;-(IBAction)press5; 还有我的 ViewController.m 节目
#import "CIAViewController.h"@interface CIAViewController ()@结尾@implementation CIAViewController-(IBAction)按{cruzia.hidden = 0;textarea.hidden = 0;playbtn.hidden = 1;tutorialbtn.hidden = 1;optionsbtn.hidden = 1;trainingbtn.hidden = 1;返回.隐藏 = 0;cruzia.text = @"播放";textarea.text = @"你好！你在玩克鲁齐亚的游戏！";}-(IBAction)press2 {cruzia.hidden = 0;textarea.hidden = 0;playbtn.hidden = 1;tutorialbtn.hidden = 1;optionsbtn.hidden = 1;trainingbtn.hidden = 1;返回.隐藏 = 0;cruzia.text = @"教程";textarea.text = @"欢迎！您正在观看Cruzia教程！";}-(IBAction)press3 {cruzia.hidden = 0;textarea.hidden = 0;playbtn.hidden = 1;tutorialbtn.hidden = 1;optionsbtn.hidden = 1;trainingbtn.hidden = 1;返回.隐藏 = 0;cruzia.text = @"选项";textarea.text = @"您现在在选项界面.您可以编辑游戏的设置！";}-(IBAction)press4 {cruzia.hidden = 0;textarea.hidden = 0;playbtn.hidden = 1;tutorialbtn.hidden = 1;optionsbtn.hidden = 1;trainingbtn.hidden = 1;返回.隐藏 = 0;cruzia.text = @"培训";textarea.text = @"这里是训练区，你可以在这里提高你的Cruzia技能！";}-(IBAction)press5 {cruzia.hidden = 0;textarea.hidden = 0;playbtn.hidden = 0;tutorialbtn.hidden = 0;optionsbtn.hidden = 0;trainingbtn.hidden = 0;返回.隐藏 = 1;cruzia.text = @"Cruzia";}- (void)viewDidLoad{textarea.hidden = 1;playbtn.hidden = 0;tutorialbtn.hidden = 0;optionsbtn.hidden = 0;trainingbtn.hidden = 0;返回.隐藏 = 1;cruzia.text = @"Cruzia";[超级viewDidLoad];}@结尾很抱歉浪费您的时间，但我已经遇到这个错误很长时间了，如果您有解决方案，我会很高兴.
问题出在哪里:
在运行时，您的视图控制器将从其 XIB/故事板中反序列化.在此过程中，它将读取您的 IB 文件中的所有对象，并开始使用 NSCoder 实例化它们.当它在您的视图中实例化这些对象时，它将读取您的故事板中的 IBOutlet 和 IBAction 连接，并开始将水合对象分配给那些在 IBOutlet 连接的属性em>设计时间，以便您可以在运行时间以编程方式访问它们.但关键在于:如果您的连接指向一个不存在的属性，那么将抛出此异常，因为它被告知某个属性确实不存在.>
发生的事情是你的 Storyboard/XIB 期望你的类有一个名为 play 的属性.正如您的界面所示，您没有名为该的属性.不过，我怀疑您曾经使用过，但将其重命名为 playbtn.
这是什么意思
<块引用>该类不符合关键播放的键值编码
这意味着它试图在幕后做这样的事情:
[self setValue:button forKey:@play"]有关键/值编码和序列化的更多启发，请找个舒适的椅子阅读键值编码编程指南 和 档案和序列化编程指南
如何修复:
在 Interface Builder 中，右键单击您的视图控制器并查看连接列表:
看看属性 play 是如何连接的，它旁边有一个黄色的小三角形?这是 Interface Builder 试图警告您您在那里设置了一个连接，但标题没有显示有该名称的 IBOutlet.
您需要做的就是点击那个小小的 x 以断开与缺失属性的连接.
如何在未来防止这种情况
无论何时更改代码中的属性，您都需要确保断开 Interface Builder 中的所有关联连接.
I'm a beginner programmer working on iPhone apps. I was wondering if anybody could help me with a bug in my app. When programming on XCode I found that my app suddenly crashed on launch after adding a little more code. The output panel showed the following error:
* Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[ setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key play.' * First throw call stack: (0x1c91012 0x10cee7e 0x1d19fb1 0xb7ae41 0xafc5f8 0xafc0e7 0xb26b58 0x230019 0x10e2663 0x1c8c45a 0x22eb1c 0xf37e7 0xf3dc8 0xf3ff8 0xf4232 0x433d5 0x4376f 0x43905 0x8eceab6 0x4c917 0x1096c 0x1194b 0x22cb5 0x23beb 0x15698 0x1becdf9 0x1becad0 0x1c06bf5 0x1c06962 0x1c37bb6 0x1c36f44 0x1c36e1b 0x1117a 0x12ffc 0x222d 0x2155) libc++abi.dylib: terminate called throwing an exception (lldb)
The code that shows up when the app terminates is as follows
#import <UIKit/UIKit.h>
#import "CIAAppDelegate.h"
int main(int argc, char *argv[])
{
@autoreleasepool {
return UIApplicationMain(argc, argv, nil, NSStringFromClass([CIAAppDelegate class]));
}
}
My ViewController.h shows:
#import <UIKit/UIKit.h>
@interface CIAViewController : UIViewController {
IBOutlet UILabel *cruzia;
IBOutlet UILabel *textarea;
IBOutlet UIButton *playbtn;
IBOutlet UIButton *tutorialbtn;
IBOutlet UIButton *optionsbtn;
IBOutlet UIButton *trainingbtn;
IBOutlet UIButton *back;
}
-(IBAction)press;
-(IBAction)press2;
-(IBAction)press3;
-(IBAction)press4;
-(IBAction)press5;
Also my ViewController.m shows
#import "CIAViewController.h"
@interface CIAViewController ()
@end
@implementation CIAViewController
-(IBAction)press {
cruzia.hidden = 0;
textarea.hidden = 0;
playbtn.hidden = 1;
tutorialbtn.hidden = 1;
optionsbtn.hidden = 1;
trainingbtn.hidden = 1;
back.hidden = 0;
cruzia.text = @"Play";
textarea.text = @"Hello! You are playing the game of Cruzia!";
}
-(IBAction)press2 {
cruzia.hidden = 0;
textarea.hidden = 0;
playbtn.hidden = 1;
tutorialbtn.hidden = 1;
optionsbtn.hidden = 1;
trainingbtn.hidden = 1;
back.hidden = 0;
cruzia.text = @"Tutorial";
textarea.text = @"Welcome! You are watching the Cruzia tutorial!";
}
-(IBAction)press3 {
cruzia.hidden = 0;
textarea.hidden = 0;
playbtn.hidden = 1;
tutorialbtn.hidden = 1;
optionsbtn.hidden = 1;
trainingbtn.hidden = 1;
back.hidden = 0;
cruzia.text = @"Options";
textarea.text = @"You are now in the Options screen. You can edit the settings of the game!";
}
-(IBAction)press4 {
cruzia.hidden = 0;
textarea.hidden = 0;
playbtn.hidden = 1;
tutorialbtn.hidden = 1;
optionsbtn.hidden = 1;
trainingbtn.hidden = 1;
back.hidden = 0;
cruzia.text = @"Training";
textarea.text = @"This is the training area. You can improve your Cruzia skills here!";
}
-(IBAction)press5 {
cruzia.hidden = 0;
textarea.hidden = 0;
playbtn.hidden = 0;
tutorialbtn.hidden = 0;
optionsbtn.hidden = 0;
trainingbtn.hidden = 0;
back.hidden = 1;
cruzia.text = @"Cruzia";
}
- (void)viewDidLoad
{
textarea.hidden = 1;
playbtn.hidden = 0;
tutorialbtn.hidden = 0;
optionsbtn.hidden = 0;
trainingbtn.hidden = 0;
back.hidden = 1;
cruzia.text = @"Cruzia";
[super viewDidLoad];
}
@end
I am sorry to waste your time but I have had this error for a long time and would like it if you had a solution.
What The Problem Is:
At runtime your view controller is going to get deserialized from its XIB/Storyboard. During this process, it's going to read all the objects that are in your IB files and start instantiating them with an NSCoder. As it is instantiating those objects in your view, it's going to read the IBOutlet and IBAction connections in your storyboard and start assigning the hydrated objects to those properties that were connected at design time so that you have programmatic access to them at run time. But here's the kicker: If you have a connection that points to a property that doesn't exist, then this exception will be thrown because it was told a property was there that really isn't.
What's happening is that your Storyboard/XIB is expecting your class to have a property called play. As your interface shows, you do not have a property called that. I suspect though, that you used to, but renamed it playbtn.
This is what is meant by
this class is not key value coding-compliant for the key play
It means it tried to do something like this under the covers:
[self setValue:button forKey:@"play"]
For additional enlightenment about Key/Value Coding and serialization, grab a comfy chair and read Key Value Coding Programming Guide and Archives and Serializations Programming Guide
How To Fix It:
In Interface Builder, right click on your view controller and see the list of connections:
See how there is a connection for the property play and it has a little yellow triangle next to it? This is Interface Builder trying to warn you that you have a connection set there, but the header isn't showing that there is an IBOutlet of that name.
All you need to do is click that little x to break the connection to the missing property.
How To Prevent This In The Future
Anytime you change a property in your code, you'll need to make sure that you break any associated connection in Interface Builder.
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