我正在制作一个应用程序来保存字段。当我点击按钮时，我收到错误。我需要获取数据并在保存后更新数据。
这是我的代码！
AppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];
NSManagedObjectContext *context =
[appDelegate managedObjectContext];
NSManagedObjectContext *serverIP;
serverIP = [NSEntityDescription insertNewObjectForEntityForName:@"IP" inManagedObjectContext:context];
[serverIP setValue:self.txtServerAdress.text forKey:@"ipaddress"];
[serverIP setValue:self.txtServerPort.text forKey:@"serverport"];
这是我得到的错误......
2015-03-26 12:12:06.914 SaphiraCrm[12306:3527354] Warning once only: Detected a case where constraints ambiguously suggest a height of zero for a tableview cell's content view. We're considering the collapse unintentional and using standard height instead.
2015-03-26 12:12:08.307 SaphiraCrm[12306:3527354] Unable to simultaneously satisfy constraints.
Probably at least one of the constraints in the following list is one you don't want. Try this: (1) look at each constraint and try to figure out which you don't expect; (2) find the code that added the unwanted constraint or constraints and fix it. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints)
(
"<NSLayoutConstraint:0x7fb4cac58470 H:[UITextField:0x7fb4cac6a2e0(243)]>",
"<NSLayoutConstraint:0x7fb4cac6cdb0 H:[UITextField:0x7fb4cac6a2e0]-(38)-| (Names: '|':UIView:0x7fb4cac67c50 )>",
"<NSLayoutConstraint:0x7fb4cac6ce00 H:|-(39)-[UITextField:0x7fb4cac6a2e0] (Names: '|':UIView:0x7fb4cac67c50 )>",
"<NSLayoutConstraint:0x7fb4cac717b0 'UIView-Encapsulated-Layout-Width' H:[UIView:0x7fb4cac67c50(375)]>"
)
Will attempt to recover by breaking constraint
<NSLayoutConstraint:0x7fb4cac58470 H:[UITextField:0x7fb4cac6a2e0(243)]>
Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
2015-03-26 12:12:08.309 SaphiraCrm[12306:3527354] Unable to simultaneously satisfy constraints.
Probably at least one of the constraints in the following list is one you don't want. Try this: (1) look at each constraint and try to figure out which you don't expect; (2) find the code that added the unwanted constraint or constraints and fix it. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints)
(
"<NSLayoutConstraint:0x7fb4cac51670 H:[UITextField:0x7fb4cac6b3c0(243)]>",
"<NSLayoutConstraint:0x7fb4cac6cef0 H:[UITextField:0x7fb4cac6b3c0]-(38)-| (Names: '|':UIView:0x7fb4cac67c50 )>",
"<NSLayoutConstraint:0x7fb4cac717b0 'UIView-Encapsulated-Layout-Width' H:[UIView:0x7fb4cac67c50(375)]>",
"<NSLayoutConstraint:0x7fb4cac6cf40 H:|-(39)-[UITextField:0x7fb4cac6b3c0] (Names: '|':UIView:0x7fb4cac67c50 )>"
)
Will attempt to recover by breaking constraint
<NSLayoutConstraint:0x7fb4cac51670 H:[UITextField:0x7fb4cac6b3c0(243)]>
Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
2015-03-26 12:12:12.387 SaphiraCrm[12306:3527354] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '+entityForName: nil is not a legal NSManagedObjectContext parameter searching for entity name 'IP''
*** First throw call stack:
(
0 CoreFoundation 0x0000000101968a75 __exceptionPreprocess + 165
1 libobjc.A.dylib 0x0000000101601bb7 objc_exception_throw + 45
2 CoreData 0x000000010063cf07 +[NSEntityDescription entityForName:inManagedObjectContext:] + 263
3 CoreData 0x000000010067896e +[NSEntityDescription insertNewObjectForEntityForName:inManagedObjectContext:] + 30
4 SaphiraCrm 0x0000000100518c4b -[SettingsViewController btnKaydet:] + 187
5 UIKit 0x0000000102168a22 -[UIApplication sendAction:to:from:forEvent:] + 75
6 UIKit 0x000000010226fe50 -[UIControl _sendActionsForEvents:withEvent:] + 467
7 UIKit 0x000000010226f21f -[UIControl touchesEnded:withEvent:] + 522
8 UIKit 0x00000001021aeb68 -[UIWindow _sendTouchesForEvent:] + 735
9 UIKit 0x00000001021af493 -[UIWindow sendEvent:] + 683
10 UIKit 0x000000010217bfb1 -[UIApplication sendEvent:] + 246
11 UIKit 0x0000000102189227 _UIApplicationHandleEventFromQueueEvent + 17700
12 UIKit 0x000000010216423c _UIApplicationHandleEventQueue + 2066
13 CoreFoundation 0x000000010189dc91 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
14 CoreFoundation 0x0000000101893b5d __CFRunLoopDoSources0 + 269
15 CoreFoundation 0x0000000101893194 __CFRunLoopRun + 868
16 CoreFoundation 0x0000000101892bc6 CFRunLoopRunSpecific + 470
17 GraphicsServices 0x0000000105abda58 GSEventRunModal + 161
18 UIKit 0x0000000102167580 UIApplicationMain + 1282
19 SaphiraCrm 0x000000010051bed3 main + 115
20 libdyld.dylib 0x0000000103d92145 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)
答案 0 :(得分：0)
您的[appDelegate managedObjectContext]似乎返回nil个对象。调试并查看它为nil的原因。修复它，你的代码应该可以正常工作。
答案 1 :(得分：0)
您必须像这样保存数据：
NSManagedObjectContext *context = [appDelegate managedObjectContext];
NSManagedObjectContext *serverIP = [NSEntityDescription insertNewObjectForEntityForName:@"IP" inManagedObjectContext:context];
serverIP.ipaddress = [key objectForKey:@"ipaddress"];
...
if (![context save:&error]) {
NSLog(@"Error: %@", [error localizedDescription]);
}
你也应该注意你的约束问题。
答案 2 :(得分：0)
您需要更改以下行：
NSManagedObjectContext *serverIP;
serverIP = [NSEntityDescription insertNewObjectForEntityForName:@"IP" inManagedObjectContext:context];
变化：
NSManagedObject *serverIP;
serverIP = [NSEntityDescription insertNewObjectForEntityForName:@"IP" inManagedObjectContext:context];