我试图深入嵌套JSon数组,我已经成功完成了以上级别的工作,但是我无法弄清楚如何进行更深入的研究。
我需要记录图像@url,并附上了一个屏幕显示,以显示需要它去的地方。
谢谢 :)
- (void)viewDidLoad
{
[super viewDidLoad];
[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
NSURL *url = [NSURL URLWithString:@"http://api.storageroomapp.com/accounts/511a4f810f66026b640007b8/collections/511a51580f66023bff000ce9/entries.json?auth_token=Zty6nKsFyqpy7Yp5DP1L&preview_api=1"];
NSURLRequest *request = [NSURLRequest requestWithURL:url];
[[NSURLConnection alloc] initWithRequest:request delegate:self];
}
-(void)connectionDidFinishLoading:(NSURLConnection *) connection{
[UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
NSDictionary *dictionary = [NSJSONSerialization JSONObjectWithData:data options:nil error:nil];
NSDictionary *arrayDictionary = dictionary[@"array"];
news = arrayDictionary[@"resources"];
[tableView reloadData];
}
-(void) connection:(NSURLConnection *)connection didFailWithError:(NSError *)error{
UIAlertView *errorView = [[UIAlertView alloc] initWithTitle:@"Error" message:@"The data could not be downloaded - please make sure you're connected to either 3G or Wi-FI" delegate:nil cancelButtonTitle:@"Dismiss" otherButtonTitles:nil];
[errorView show];
[UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
}
-(int)numberOfSectionsInTableView:(UITableView *)tableView{
return 1;
}
-(int)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
return [news count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
NSDictionary *newsItem = news[[indexPath row]];
NSString *title = newsItem[@"title"];
NSString *date = newsItem[@"date"];
NSString *thumb = newsItem[@"tablethumb"];
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"MainCell"];
if (cell == nil) {
cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:@"MainCell"];
[[cell textLabel] setText:title];
[[cell detailTextLabel] setText:date];
if((NSNull *)thumb == [NSNull null]){
NSLog(@"no image");
} else{
NSLog(@ "image = %@", thumb);
}
}
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
return cell;
}
最佳答案
要遍历嵌套对象,可以使用valueForKeyPath
方法,并使用点语法来深入层次结构。
这样的事情将从您的url
字典中获取newsItem
值:
NSDictionary *newsItem = news[[indexPath row]];
NSString *thumbUrl = [newsItem valueForKeyPath:@"tablethumb.url"];
PS。如果您确实拥有以
@
开头的属性,那么自valueForKeyPath
is a special token used as an operator以来,您可能会因为使用@
而遇到麻烦。在这种情况下,您可以改为执行以下操作:NSDictionary *newsItem = news[[indexPath row]];
id tablethumb = [newsItem objectForKey:@"tablethumb"];
NSString *thumbUrl = @"";
// Check if not null and access the @url
if (tablethumb != [NSNull null])
thumbUrl = tablethumb[@"@url"];