iphone - 我无法从另一个类保存检索 NSurl？

Question

我有一个返回 NSUrl 的函数，我想在另一个类中使用它。但是当我尝试在其他类(class)中检索它时，它给了我空值。这是我的头等舱

@interface UOEventDetailController : UIViewController {
NSURL *imgData;
}
@property(nonatomic, retain)NSURL *imgData;
-(NSURL *)imgData;

@implementation UOEventDetailController
@synthesize imgData;

.m 文件

-(NSURL *)imgData{
UOEventPost *post = (UOEventPost *)self.event;
NSURL *url = [NSURL URLWithString:post.postImageURL];
return url;
}

我想检索此类中的 URL

@class UOEventDetailController;

@interface UOEnlargeImageViewController : UIViewController {
IBOutlet UIImageView *enlargedImage;

}
@property (nonatomic, retain) UOEventDetailController *controller;
@property (nonatomic, retain) IBOutlet UIImageView *enlargedImage;

.m 文件

@implementation UOEnlargeImageViewController
@synthesize controller;
@synthesize enlargedImage;

- (void)viewDidLoad
{
[super viewDidLoad];
self.title = @"Enlarged Image";
controller = [[UOEventDetailController alloc]init];
NSURL *url = [controller imgData];
NSLog(@"%@",url);


}
@end

我可以检索除 post.postImageUrl 之外的对象。例如我输入了像@“omg”，@“god”这样的字符串，而不是post.postImageUrl它在我的其他类(class)中被检索...

编辑

-(IBAction)enlargeImg{
UOEventPost *post = (UOEventPost *)self.event;
UOEnlargeImageViewController *enlarge = [[UOEnlargeImageViewController alloc]initWithNibName:nil bundle:nil];
enlarge.temp = post.postImageURL;
[self.navigationController pushViewController:enlarge animated:YES];
[suggestPopupView removeFromSuperview];
[enlarge release];
}

Answer 1

这是因为您正在创建一个新对象。而new对象的相关属性为空，因此url也为空。