块内存泄漏

Question

我该如何解读这张照片？

con是一个NSURLConnection子类，其中有一个块responseHandler作为属性保存在其中

执行块后立即写

con.responseHandler = nil;
con = nil;

这张图片是应用程序分析的结果，但我不确定如何理解它

- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
     WBURLConnectionWithResponseHandler *con = (WBURLConnectionWithResponseHandler *)connection;
    NSData *data = [con data];
    NSString *responseString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
    NSLog(@"Data recieved:%@",responseString);

    ServerResponse *response = [ServerResponse handleServerResponse:[con rawResponse] andResponseString:responseString andError:nil];
    if(con.responseHandler){
        con.responseHandler(response);
    }
    if(response.statusCode>=500){
        if(!self.alert){
            self.alert = [[UIAlertView alloc]initWithTitle:WBString(kLocalizable_alert) message:WBString(kLocalizable_serverError) delegate:nil cancelButtonTitle:WBString(kLocalizable_ok) otherButtonTitles: nil];
            [self.alert show];
        }else {
            if(![self.alert isVisible]){
                [self.alert setMessage:WBString(kLocalizable_serverError)];
                [self.alert show];
            }
        }
    }
    con.responseHandler = nil;
    [con.data  setLength:0];
    [[UIApplication sharedApplication]setNetworkActivityIndicatorVisible:NO];
}


typedef void (^ServerResponseHandler)(ServerResponse *response);

这是我的WBURLConnection定义

@interface WBURLConnectionWithResponseHandler : NSURLConnection
@property (nonatomic,strong) ServerResponseHandler responseHandler; <== if i put it to weak or assign, it is deallocated before i can use it
@property (nonatomic,strong) NSHTTPURLResponse *rawResponse;
@property (nonatomic,strong)NSMutableData *data;
@property (nonatomic,assign)NSInteger retries;
@property (nonatomic,strong)NSMutableString *retryCount;
@property (nonatomic,strong)NSString *requestBody;
@property (nonatomic,strong)NSString *stam;
-(BOOL)shouldRetryRequest:(NSError *)error;
@end