exc_bad_access從NSKeyedUnarchiver返回的對象

Question

我無法從保存的數據加載符合NSCoding協議的自定義類的實例。我的課有一個UIImage屬性，當我分配一個新的UIImage它的程序崩潰與exc_bad_access。

在視圖控制器我宣佈我的對象，像這樣：

@interface SomeViewController : UIViewController { 
    IBOutlet UIImageView *imageView; 
    SomeClass *myObject; 
} 

@property (nonatomic, retain) SomeClass *myObject; 
@property (nonatomic, retain) IBOutlet UIImageView *imageView; 

然後在.m文件它被用作如下：

@synthesize myObject; 
@synthesize imageView; 

-(void)viewDidLoad{ 
    myObject = [NSKeyedUnarchiver unarchiveObjectWithFile:someDataPath]; 
    imageView.image = myObject.image; 
} 

到目前爲止好。但後來我選了一個新的形象，並嘗試將其設置爲myObject的「圖像」屬性，至於我可以通過代碼單步講，這將引發一個EXC_BAD_ACCESS

-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info { 
    [picker dismissModalViewControllerAnimated:YES]; 
    UIImage *image = [info objectForKey:@"UIImagePickerControllerOriginalImage"]; 
    [imageView setImage:image]; 
    myObject.image = image; 
} 

，它是導致exc_bad_access的最後一行。我究竟做錯了什麼？

Answer 1

您必須保留myObject的：

self.myObject = [NSKeyedUnarchiver unarchiveObjectWithFile:someDataPath];