Question

我是xcode的新手并且遵循这个RestKit教程： https://github.com/RestKit/RKGist/blob/master/TUTORIAL.md 我成功地完成了它。我正在重新审视并定制它以满足我的需求，并且由于某种原因，在很早的时候（甚至在我做出任何真正的偏差之前）应用程序在模拟器上崩溃了。我设置了数据模型，配置了RestKit和CoreData，然后在tut中进行了第一次模拟失败。这是我尝试运行时遇到的错误：

    2013-06-09 18:37:10.121 marko1[16183:c07] I restkit:RKLog.m:34 RestKit logging initialized...
2013-06-09 18:37:10.148 marko1[16183:c07] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[NSURL initFileURLWithPath:]: nil string parameter'
*** First throw call stack:
(0x1b24012 0x1949e7e 0x1b23deb 0x13609b1 0x136093b 0x26db 0x88b157 0x88b747 0x88c94b 0x89dcb5 0x89ebeb 0x890698 0x25c0df9 0x25c0ad0 0x1a99bf5 0x1a99962 0x1acabb6 0x1ac9f44 0x1ac9e1b 0x88c17a 0x88dffc 0x25dd 0x2505 0x1)
libc++abi.dylib: terminate called throwing an exception

以上，它显示main.m文件中的这行代码：

 #import <UIKit/UIKit.h>

#import "AppDelegate.h"

int main(int argc, char *argv[])
{
    @autoreleasepool {
        return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
    }
}

我无法理解，因为我从我创建的功能版本克隆了代码，但它仍然崩溃。任何帮助都会很大 - 即使它只是解释这意味着什么是抽象的以及如何处理攻击这个问题。提前谢谢！

这是AppDelegate.m文件，我调用NSURL（以及异常断点指向我的地方）。

#import "AppDelegate.h"
#import <RestKit/RestKit.h>
#import "MasterViewController.h"

@implementation AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    NSError *error = nil;
    NSURL *modelURL = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"Marko1" ofType:@"momd"]];

    NSManagedObjectModel *managedObjectModel = [[[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL] mutableCopy];
    RKManagedObjectStore *managedObjectStore = [[RKManagedObjectStore alloc] initWithManagedObjectModel:managedObjectModel];

    //Initialize the Core Data Stack
    [managedObjectStore createPersistentStoreCoordinator];

    NSPersistentStore __unused *persistentStore = [managedObjectStore addInMemoryPersistentStore:&error];
    NSAssert(persistentStore, @"Failed to add persistent store: %@", error);

    [managedObjectStore createManagedObjectContexts];

    //Set the default store shared instance
    [RKManagedObjectStore setDefaultStore:managedObjectStore];

    //Override point for customization after application launch.
    UINavigationController *navigationController = (UINavigationController *)self.window.rootViewController;
    MasterViewController *controller = (MasterViewController *)navigationController.topViewController;
    controller.managedObjectContext = managedObjectStore.mainQueueManagedObjectContext;
    return YES;
}
@end

Answer 1

我看到过这种崩溃，原因是路径返回nil

NSURL *modelURL = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"Marko1" ofType:@"momd"]];

1.记录你的路径

 NSLog(@"%@",[[NSBundle mainBundle] pathForResource:@"Marko1" ofType:@"momd"]);

2. momd尝试使用mom

Answer 2

您是否尝试检查该文件是否存在？

NSURL *test;
if ([[NSBundle mainBundle] pathForResource:@"Marko1" ofType:@"momd"]) {
    test = [[NSURL alloc] initFileURLWithPath:[[NSBundle mainBundle] pathForResource:@"Marko1" ofType:@"momd"]];
} else {
    NSLog(@"File could not be located");
}

或尝试以这种方式使用它：

NSString *modelPath = [[NSBundle mainBundle] pathForResource:@"Makro1" ofType:@"momd"];
NSManagedObjectModel *objectModel = [[NSManagedObjectModel alloc] initWithContentsOfURL:[NSURL fileURLWithPath:modelPath]];

为什么xcode和RestKit从NSURL nil字符串参数崩溃

2 个答案: