NSURL代表didReceiveData方法不叫

Question

我知道這已在很多其他帖子中討論過，但我需要發佈它，因爲這些線程不幸我不幸幫助我。我試圖連接到返回響應GET request.I JSON格式的一些數據的軌服務器已經實現了NSConnectionDataDelegate四種方法如下面列出

#pragma mark - 
#pragma mark NSURLConnectionDataDelegate 

-(void) connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response { 

    NSLog(@"didReceiveResponse"); 
    [resultData setLength:0]; 

} 


-(void) connection:(NSURLConnection *)connection didReceiveData:(NSData *)data { 

    NSLog(@"didReceiveData"); 
[resultData appendData:data]; 


} 

-(void) connection:(NSURLConnection *)connection didFailWithError:(NSError *)error { 

    NSLog(@"didFailWithError"); 

    NSString *errDesc = [NSString stringWithFormat:@"Connection failed: %@", [error description]]; 
    NSLog(@"%@",errDesc); 

} 

-(void) connectionDidFinishLoading:(NSURLConnection *)connection { 

    NSLog(@"didReceiveLoading"); 
} 

在connectionDidFinishDownloading方法（未上市）我執行JSON解析，但由於從未調用過didReceiveData方法，因此resultData爲空。

didReceiveResponse方法被調用，因爲我看到消息被記錄。服務器正在本地主機上運行，​​所以我可以確認收到請求並使用Charles我知道響應以JSON格式正確接收。所以在服務器端似乎沒有問題。但didReceiveData方法永遠不會被調用。 didFailWithError方法都不是。

是否有人可以幫助我？我無法弄清楚我做錯了什麼。這是我第一次與NSURL合作，所以非常感謝。我正在使用ARC在iOS 5上工作。

薩蒂揚

編輯：

NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"%@%@?%@", kDevelopmentMode ? kLocalHost : kHost, endpoint, parameters]]; 
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url]; 
NSURLConnection *urlConnection = [[NSURLConnection alloc] initWithRequest:request delegate:self]; 

Answer 1

我的猜測是，您的應用程序是沒有得到回數據。試試這個與你的網址，它會讓你知道返回的原始數據，如果數據返回jsonserialization。

NSData *returnedData = [[NSData alloc] initWithContentsOfURL:[NSURL URLWithString:@"http://yourURLHere"]]; 

if (returnedData) { 
    NSLog(@"returnedData:%@", returnedData); 

    NSDictionary *jsonDict = [NSJSONSerialization JSONObjectWithData:returnedData options:kNilOptions error:Nil]; 
    NSLog(@"jsonDict:%@", jsonDict); 
} 
else 
    NSLog(@"Got Nothing"); 

，如果你的日誌顯示的原始數據和JSON數據，那麼這個問題是與您的NSURLRequest。但是如果日誌顯示「沒有任何東西」，那麼你想要得到的東西存在問題。

編輯

#import <UIKit/UIKit.h> 

@interface AsyncImage : UIImageView 
{  
    NSMutableData *activeDownload; 
    NSURLConnection *imageConnection; 
} 
@property (nonatomic, retain) NSMutableData *activeDownload; 
@property (nonatomic, retain) NSURLConnection *imageConnection; 
- (void)loadImageFromURL:(NSURL*)url; 
@end 



#import "AsyncImage.h" 

@implementation AsyncImage 
@synthesize activeDownload; 
@synthesize imageConnection; 

- (void)dealloc 
{ 
    [super dealloc]; 
    NSLog(@"dealloc AsyncImage"); 

    [activeDownload release]; 
    [imageConnection cancel]; 
    [imageConnection release]; 
} 

- (void)cancelDownload 
{ 
    [self.imageConnection cancel]; 
    self.imageConnection = nil; 
    self.activeDownload = nil; 
} 


#pragma mark - 
#pragma mark Download support (NSURLConnectionDelegate) 

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data 
{ 
    [self.activeDownload appendData:data]; 
} 

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error 
{ 
    // Clear the activeDownload property to allow later attempts 
    self.activeDownload = nil; 

    // Release the connection now that it's finished 
    self.imageConnection = nil; 
} 

- (void)connectionDidFinishLoading:(NSURLConnection *)connection 
{ 
    self.image = [UIImage imageWithData:self.activeDownload]; 

    self.activeDownload = nil; 

    // Release the connection now that it's finished 
    self.imageConnection = nil; 
} 

- (void)loadImageFromURL:(NSURL*)url { 
    if (self.imageConnection!=nil) { [imageConnection release]; } //in case we are downloading a 2nd image 

    self.activeDownload = [NSMutableData data]; 
    // alloc+init and start an NSURLConnection; release on completion/failure 
    NSURLConnection *conn = [[NSURLConnection alloc] initWithRequest: 
          [NSURLRequest requestWithURL:url] delegate:self]; 
    self.imageConnection = conn; 
    [conn release]; 
} 

@end 

Answer 2

套裝NSURLConnectionDelegate在.h文件。