Question

下午好，

我正在使用TableViewController工作的最后一步，我遇到了DetailViewController的问题。

在这里你找到我的Segue代码：我在声明“[self.carMakes objectAtIndex：[myIndexPath row]]”时遇到问题，因为我收到错误：“ [__ NSArrayM objectAtIndex：]：索引0超出界限空数组'“并且我已经搜索了错误并且它是我的数组，它是空的。

我将在下面发布更多代码，如果这有助于你找到我做错的地方，因为我不知道为什么数组是空的，因为它在TableVlewController中显示一切正常。

CarTablewViewController.m

@implementation CarTableViewController

@synthesize carMakes = _carMakes;
@synthesize carModels = _carModels;
@synthesize carImages = _carImages;
//@synthesize jsonArray = _jsonArray;

- (void)viewDidLoad
{
    [super viewDidLoad];

    [self fetchJson];

    [self.tableView reloadData];

}

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    // Return the number of sections.
    return 1;
}


- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    // Return the number of rows in the section.
    return [_jsonArray count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"carTableCell";

    CarTableViewCell *cell = [tableView
                              dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[CarTableViewCell alloc]
                initWithStyle:UITableViewCellStyleDefault
                reuseIdentifier:CellIdentifier];
    }

    cell.makeLabel.text = [[_jsonArray objectAtIndex:indexPath.row] valueForKey:@"id"];

    cell.modelLabel.text = [[_jsonArray objectAtIndex:indexPath.row] valueForKey:@"user"];

    NSURL * imageURL = [NSURL URLWithString:[[_jsonArray objectAtIndex:indexPath.row] valueForKey:@"imagen"]];
    NSData * imageData = [NSData dataWithContentsOfURL:imageURL];
    UIImage * carPhoto = [UIImage imageWithData:imageData];

    cell.carImage.image = carPhoto;

    return cell;
}

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if ([[segue identifier] isEqualToString:@"ShowCarDetails"])
    {
        CarDetailViewController *detailViewController = [segue destinationViewController];

        NSIndexPath *myIndexPath = [self.tableView indexPathForSelectedRow];

        NSLog(@"TEST");

        detailViewController.carDetailModel = [[NSMutableArray alloc]
                                               initWithObjects:

                                               [self.carMakes objectAtIndex:[myIndexPath row]],
                                               [self.carModels objectAtIndex:[myIndexPath row]],
                                               [self.carImages objectAtIndex:[myIndexPath row]],

                                               nil];
    }
}

-(void)fetchJson {
    dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
    dispatch_async(queue, ^{

        NSString * urlString = [NSString stringWithFormat:@"http://website.com/service.php"];
        NSURL * url = [NSURL URLWithString:urlString];
        NSData * data = [NSData dataWithContentsOfURL:url];

        self.carModels = [[NSMutableArray alloc] init];
        self.carMakes = [[NSMutableArray alloc] init];
        self.carImages = [[NSMutableArray alloc] init];
        @try
        {
            NSError *error;
            [_jsonArray removeAllObjects];
            _jsonArray = [NSJSONSerialization
                         JSONObjectWithData:data
                         options:NSJSONReadingMutableContainers|NSJSONReadingMutableLeaves
                         error:&error];
        }
        @catch (NSException * e)
        {
            NSLog(@"Exception: %@", e);
        }
        @finally
        {
            [self.tableView reloadData];
        }
    }
                   );
}

@end

提前致谢。

Answer 1

您的tableview正在使用[_jsonArray objectAtIndex:indexPath.row]来填充值。在-(void)fetchJson中，您正在初始化数组，但未使用任何数据加载它们

因此，当您执行此操作[self.carMakes objectAtIndex:[myIndexPath row]]时，该数组不包含任何内容

您的表视图正在使用此代码来获取make和model ...

cell.makeLabel.text = [[_jsonArray objectAtIndex:indexPath.row] valueForKey:@"id"];

cell.modelLabel.text = [[_jsonArray objectAtIndex:indexPath.row] valueForKey:@"user"];

但是你的Segue正在这样做

[self.carMakes objectAtIndex:[myIndexPath row]],
[self.carModels objectAtIndex:[myIndexPath row]],

在您的抓取中，您不会填充self.carMakes或self.carModels。填充它们或使用

[[_jsonArray objectAtIndex:[myIndexPath row]] valueForKey:@"id"],
[[_jsonArray objectAtIndex:[myIndexPath row]] valueForKey:@"user"],

在你的Segue中

Segue - 索引0超出空数组的边界

1 个答案: