Question

   -(void)method1
        {
          [self method2];     
          [self method3]; //After finishing execution of method2 and its delegates I want to execute method3
        }

这里，method2在调用时运行，但在执行其委托方法之前，method3开始执行。怎么避免呢？任何建议或代码，请

我在方法2

中调用了与其代理人的nsurl连接

 -(void)method2
    {
    ....
       connection= [[NSURLConnection alloc] initWithRequest:req delegate:self ];
    ....
    }


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

        }

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

        }
..
..

Answer 1

使用块 - 处理起来会更容易：

[NSURLConnection sendAsynchronousRequest:request
                                   queue:[[NSOperationQueue alloc] init]

                       completionHandler:^(NSURLResponse *response,
                                           NSData *data,
                                           NSError *error)
 {

     if ([data length] >0 && error == nil) {
         // parse your data here 

         [self method3];

         dispatch_async(dispatch_get_main_queue(), ^{

               // call method on main thread, which can be used to update UI stuffs
               [self updateUIOnMainThread];
         }); 
     }
     else if (error != nil) {
        // show an error
     }
 }];

Answer 2

-(void) connection:(NSURLConnection *) connection didReceiveData:(NSData *) 
{
    [self method3]
}

Answer 3

您正在使用异步网址连接。那个方法3在方法2完成之前被触发。要解决您的问题，请使用此

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
     [self method3];
}

绝对可以。

等到委托方法在ios中完成执行

3 个答案: