在ViewDidLoad之后NSMutableArray为空

在tableView中加载的数据是我的描述。在ViewDidLoad之后NSMutableArray为空

我想从API中添加对象，它以JSON形式将数据反馈到NSMutableArray，但它不会使用tableview加载。
我可以看到数组设置好，但它不会加载到tableview，直到我尝试滚动tableview。

这是非常烦人的，无法弄清楚为什么善意帮我弄清楚。

这里是我的代码 -

- (void)viewDidLoad { 

    [SVProgressHUD showWithStatus:@"Please wait ..."]; 


    //get the bookings 
    [self getBookings]; 

    [super viewDidLoad]; 

    [self.tableView reloadData]; 
}

-(void) getBookings 
{ 
    [email protected]"41"; 
    bookingsList=[[NSMutableArray alloc] init]; 

    NSString *urlAsString = [NSString stringWithFormat:@"http://www.webservice.com/cleaning/api/booking/show/%@/%d",uid,0]; 
    NSURL *url = [[NSURL alloc] initWithString:urlAsString]; 
    NSLog(@"%@", urlAsString); 

    [NSURLConnection sendAsynchronousRequest:[[NSURLRequest alloc] initWithURL:url] queue:[[NSOperationQueue alloc] init] completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) { 

     if (error) { 

      NSLog(@"URL Session Task Failed: %@", [error localizedDescription]); 
     } 
     else { 

      NSArray *postsFromResponse = [NSJSONSerialization JSONObjectWithData: data options:NSJSONReadingMutableContainers error:nil]; 

      NSLog(@"Count %d", postsFromResponse.count); 

      NSLog(@"JSON: %@", postsFromResponse); 

      //remove all objects from array 
      [self.bookingsList removeAllObjects]; 

      for (NSDictionary *attributes in postsFromResponse) { 
       booking *bk = [[booking alloc] init]; 
       [bk setAddress:[attributes objectForKey:@"Address"]]; 
       [bk setBookingId:[attributes objectForKey:@"BookingID"]]; 
       [bk setServiceDate:[attributes objectForKey:@"ServiceDate"]]; 
       [bk setClientName:[attributes objectForKey:@"ClientName"]]; 
       [bk setStatus:[attributes objectForKey:@"Status"]]; 
       [bk setServiceTime:[attributes objectForKey:@"ServiceTime"]]; 
       [bk setPrice:[attributes objectForKey:@"Price"]]; 
       [bk setCleanType:[attributes objectForKey:@"CleanType"]]; 
       [bk setNumOfHours:[attributes objectForKey:@"NumOfHours"]]; 

       //add to array 
       [self.bookingsList addObject:bk]; 

      } 
      NSLog(@"Records found -%lu",(unsigned long)[bookingsList count]); 
      [self.tableView reloadData]; 
      if(bookingsList.count==0) 
      { 
       UIAlertView* alertView = [[UIAlertView alloc] initWithTitle:@"No Data Alert!" 
                    message:@"No bookings found!" delegate:nil 
                  cancelButtonTitle:@"OK" otherButtonTitles:nil]; 
       //[alertView show]; 
       [alertView performSelectorOnMainThread:@selector(show) withObject:nil waitUntilDone:YES]; 
      } 

     } 
    }]; 


    [SVProgressHUD dismiss]; 


}

#pragma mark - TableView Delegate Methods 
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { 
    return 1; 
} 

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { 

    NSLog(@"Total rows - %lu", (unsigned long)[self.bookingsList count]); 
    return [self.bookingsList count]; 
}

来源

2016-08-19 Tajuddin

首先，您是否成功获得服务器的响应？ – user3182143

是的，我确实得到了回应，并显示了JSON数据。正如我所说，它显示当我尝试滚动tableview。 – Tajuddin

使用这个它会帮助你

- (void)viewDidLoad { 

    [SVProgressHUD showWithStatus:@"Please wait ..."]; 


    //get the bookings 
    [self getBookings]; 

    [super viewDidLoad]; 
} 

-(void) getBookings 
{ 

    [email protected]"41"; 

    bookingsList=[[NSMutableArray alloc] init]; 

    NSString *urlAsString = [NSString stringWithFormat:@"http://www.webservice.com/cleaning/api/booking/show/%@/%d",uid,0]; 
    NSURL *url = [[NSURL alloc] initWithString:urlAsString]; 
    NSMutableURLRequest *request=[NSMutableURLRequest requestWithURL:urlAsString]; 
    [request setHTTPMethod:GET_REQUEST]; 
    [request setValue:@"application/json" forHTTPHeaderField:@"Content-Type"]; 
    NSURLSession *session = [NSURLSession sharedSession]; 
    NSURLSessionDataTask *task = [session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *err) 
            { 

             if (error) { 

              NSLog(@"URL Session Task Failed: %@", [error localizedDescription]); 
             } 
             else { 

              NSArray *postsFromResponse = [NSJSONSerialization JSONObjectWithData: data options:NSJSONReadingMutableContainers error:nil]; 

              NSLog(@"Count %d", postsFromResponse.count); 

              NSLog(@"JSON: %@", postsFromResponse); 

              //remove all objects from array 
              [self.bookingsList removeAllObjects]; 

              for (NSDictionary *attributes in postsFromResponse) { 
               booking *bk = [[booking alloc] init]; 
               [bk setAddress:[attributes objectForKey:@"Address"]]; 
               [bk setBookingId:[attributes objectForKey:@"BookingID"]]; 
               [bk setServiceDate:[attributes objectForKey:@"ServiceDate"]]; 
               [bk setClientName:[attributes objectForKey:@"ClientName"]]; 
               [bk setStatus:[attributes objectForKey:@"Status"]]; 
               [bk setServiceTime:[attributes objectForKey:@"ServiceTime"]]; 
               [bk setPrice:[attributes objectForKey:@"Price"]]; 
               [bk setCleanType:[attributes objectForKey:@"CleanType"]]; 
               [bk setNumOfHours:[attributes objectForKey:@"NumOfHours"]]; 

               //add to array 
               [self.bookingsList addObject:bk]; 

              } 
              NSLog(@"Records found -%lu",(unsigned long)[bookingsList count]); 
              dispatch_async(dispatch_get_main_queue(),^{ 
               [self.tableView reloadData]; 
              }); 
              if(bookingsList.count==0) 
              { 
               UIAlertView* alertView = [[UIAlertView alloc] initWithTitle:@"No Data Alert!" 
                            message:@"No bookings found!" delegate:nil 
                         cancelButtonTitle:@"OK" otherButtonTitles:nil]; 
               //[alertView show]; 
               [alertView performSelectorOnMainThread:@selector(show) withObject:nil waitUntilDone:YES]; 
              } 

             } 
            }]; 
    [task resume]; 


    [SVProgressHUD dismiss]; 


} 


- (void)didReceiveMemoryWarning { 
    [super didReceiveMemoryWarning]; 
    // Dispose of any resources that can be recreated. 
} 

#pragma mark - Table view data source 

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { 

    return 1; 
} 

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { 

    NSLog(@"Total rows - %lu", (unsigned long)[self.bookingsList count]); 
    return [self.bookingsList count]; 
}

来源

2016-08-19 07:30:55 PinkeshGjr

感谢您的建议，dispatch_async（dispatch_get_main_queue（），^ {self.tableView reloadData]; }）;似乎解决了这个问题。我必须替换[request setHTTPMethod：GET_REQUEST];与request.HTTPMethod = @“GET”; – Tajuddin

编码约定：背杂物任何属性都应该以下划线开头。像_bookingsList一样。如果你没有遵循这个连接，我们就不知道没有完整的源代码，在bookingsList的任务中将存储结果。

来源

2016-08-19 07:42:45 gnasher729

在ViewDidLoad之后NSMutableArray为空

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