Question

我想显示来自网址的json数据。 Everything Works数据数组只能在load部分中访问。当我使用它来计算计数时，它会给出NULL，但内部确实加载它有效。问题是什么。

.h文件

@interface ViewController : UIViewController<UITableViewDataSource,UITableViewDelegate>
{

NSDictionary *dictArray;
NSString *title;
}

.m文件

#import "ViewController.h"
#import "AFNetworking.h"


#import "AFHTTPRequestOperation.h"


@interface ViewController ()
{
  NSArray *data;
}
@end

@implementation ViewController

- (void)viewDidLoad {
[super viewDidLoad];
AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
[manager GET:[NSString stringWithFormat:@"sampleUrl"]
  parameters:nil
     success:^(AFHTTPRequestOperation *operation, id responseObject) {
         NSDictionary *weather = (NSDictionary *)responseObject;

         data = [weather objectForKey:@"slider"];
         NSLog(@"%@",data); // Works Fine
     }
     failure:^(AFHTTPRequestOperation *operation, NSError *error) {
         UIAlertView *av = [[UIAlertView alloc] initWithTitle:@"Error Retrieving Weather" message:[NSString stringWithFormat:@"%@", error] delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
         [av show];
     }];

}

- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];

}
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return  [data count]; // doesn;t work
}

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
   NSString *cellIdentifier = @"cell";
   UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];


dictArray = [data objectAtIndex:indexPath.row];
   cell.textLabel.text = [dictArray objectForKey:@"title"];
  NSLog(@"%@",data); // Doesn;t work displays NULL

return cell;}


@end

Answer 1

在AFNetworking管理器的成功块中，重新加载tableView。表现在在Web服务获得响应之前加载。

 success:^(AFHTTPRequestOperation *operation, id responseObject) {
     NSDictionary *weather = (NSDictionary *)responseObject;

     data = [weather objectForKey:@"slider"];
     NSLog(@"%@",data); // Works Fine
     [yourTableView reloadData];

 }

使用AFNetworking从URL显示JSON数据

1 个答案: