Question

我使用performSelector以不同的时间戳每隔几秒调用一次URLRequest。但是，数据处理可能需要比我定义的时间更长的时间。

  [self performSelector:@selector(process) withObject:nil afterDelay:1.6];

下面的部分显示了该方法被称为

 -(void)process
{
    timestamp=[NSString stringWithFormat:@"%1.f",progressValue];
    NSString *contour=@"&bandschema=4";
    NSString *url6=[NSString stringWithFormat:@"http://contour.php?  callback=contourData%@&type=json&timestamp=%@%@",timestamp,timestamp,contour];        
    NSURL *url1=[NSURL URLWithString:url6];
  __weak ASIHTTPRequest *request1 = [ASIHTTPRequest requestWithURL:url1];
        [request1 setCompletionBlock:^{
            responseString = [request1 responseString];
                [self plotPoint:self.responseString];

        }];
        [request1 setFailedBlock:^{

            NSError *error=[request1 error];
            NSLog(@"Error: %@", error.localizedDescription);
        }];
        [request1 startAsynchronous];
    }

这部分是分析数据的起点。

-(void)plotPoint:(NSString *)request
{
    NSArray *polygonArray = [[dict  objectForKey:@"data"]valueForKey:@"polygon"];
    NSArray *valleyPolygonArray = [[dict objectForKey:@"valley"]valueForKey:@"polygon"];
    CLLocationCoordinate2D *coords;
}

然而，有时候时间间隔不足以获得新数据，尤其是当互联网连接不好时。

你可以指导我吗？我怎么能处理这个问题？什么是最佳解决方案？

Answer 1

为什么在得到如下答案后不要致电process，

-(void)process
{
    timestamp=[NSString stringWithFormat:@"%1.f",progressValue];
    NSString *contour=@"&bandschema=4";
    NSString *url6=[NSString stringWithFormat:@"http://contour.php?  callback=contourData%@&type=json&timestamp=%@%@",timestamp,timestamp,contour];        
    NSURL *url1=[NSURL URLWithString:url6];
  __weak ASIHTTPRequest *request1 = [ASIHTTPRequest requestWithURL:url1];
        [request1 setCompletionBlock:^{
            responseString = [request1 responseString];
            [self plotPoint:self.responseString];

            if (somecondition)//based on some condition to break the chain when needed
              [self process];    
        }];
        [request1 setFailedBlock:^{

            NSError *error=[request1 error];
            NSLog(@"Error: %@", error.localizedDescription);

            if (somecondition)//based on some condition to break the chain when needed
              [self process];        
        }];
        [request1 startAsynchronous];
    }

这样，您可以在获得创建新请求的响应后将1.6保留为确切的时间间隔。

PerformSelector用于获取具有不同时间戳-iOS的URL

1 个答案: