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iOS

Blog Reader app not working

App stops running and says: return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class])); Thread 1 signal SIGABART.

Here's my code:

TableViewController.m:
 #import "TableViewController.h"

@interface TableViewController ()

@end

@implementation TableViewController

- (id)initWithStyle:(UITableViewStyle)style
{
    self = [super initWithStyle:style];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];

    NSError *error = nil;

    NSURL *blogURL = [NSURL URLWithString:@"http://blog.teamtreehouse.com/api/get_recent_summary/"];

    NSData *jsonData = [NSData dataWithContentsOfURL:blogURL];

    NSDictionary *dataDictionary = [NSJSONSerialization JSONObjectWithData:jsonData options:0 error:&error];

    self.blogPosts = [dataDictionary objectForKey:@"posts"];




}

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

#pragma mark - Table view data source

- (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 self.blogPosts.count;
}

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

    NSDictionary *blogPost = [self.blogPosts objectAtIndex:indexPath.row];

    cell.textLabel.text = [blogPost valueForKey:@"title"];
    cell.detailTextLabel.text = [blogPost valueForKey: @"author"];
    return cell;
}

/*
// Override to support conditional editing of the table view.
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Return NO if you do not want the specified item to be editable.
    return YES;
}
*/

/*
// Override to support editing the table view.
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
    if (editingStyle == UITableViewCellEditingStyleDelete) {
        // Delete the row from the data source
        [tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
    }   
    else if (editingStyle == UITableViewCellEditingStyleInsert) {
        // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
    }   
}
*/

/*
// Override to support rearranging the table view.
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath
{
}
*/

/*
// Override to support conditional rearranging of the table view.
- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Return NO if you do not want the item to be re-orderable.
    return YES;
}
*/

#pragma mark - Table view delegate

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Navigation logic may go here. Create and push another view controller.
    /*
     <#DetailViewController#> *detailViewController = [[<#DetailViewController#> alloc] initWithNibName:@"<#Nib name#>" bundle:nil];
     // ...
     // Pass the selected object to the new view controller.
     [self.navigationController pushViewController:detailViewController animated:YES];
     */
}

@end

TableViewController.h:

#import <UIKit/UIKit.h>

@interface TableViewController : UITableViewController

@property (nonatomic,strong) NSArray *blogPosts;

@end

2 Answers

Amit Bijlani
STAFF
Amit Bijlani
Treehouse Guest Teacher

A SIGABART error usually denotes a runtime error. There's no issue with your code so you can try a few things:

  1. Since you are getting back the error object from parsing your JSON you can add an NSLog to see if there's any error. In the last line of your viewDidLoad method simply add `NSLog(@"%@",error);

  2. Add an exception breakpoint which will halt execution of your app at the line where the error occurs.

  3. Add breakpoints yourself and step through your code to see where it breaks.

Thanks, all I had to do was register the dequeReusableCell Method, and now the app works like it should.

How do you register it?