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iOS

TJ Rogers
TJ Rogers
8,758 Points
Posted by TJ Rogers
TJ Rogers
8,758 Points

Row Selector one step behind

Having trouble with Row selection in the Blog Reader project. in the NSLog that I set up to test the row selection operation, when I first select a row nothing happens. Then when I select another row, the NSLog returns the index number of the first row that was selected. Then when I select another row, it returns the index number of the row that was previously selected, and so forth. In other words, the selector operation is always one step behind the actual selection.

I don't know if this is related. But the row selector code in the tutorial vid is pre-populate in the TableViewController.m file. But in the most recent version of X-Code, it does not pre-populate and I needed to copy the code as it is written in the vid manually. Perhaps there is another step I need to take besides just copying the code? I'm at a loss here. In any case, here is my code. Thanks!

#import "TableViewController.h"
#import "BlogPost.h"
@interface TableViewController ()

@end

@implementation TableViewController

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

- (void)viewDidLoad
{
    [super viewDidLoad];


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

    NSData *jsonData = [NSData dataWithContentsOfURL:blogURL];

    NSError *error = nil;

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

    self.blogPosts = [NSMutableArray array];

    NSArray *blogPostsArray = [dataDictionary objectForKey:@"posts"];


    for (NSDictionary *bpDictionary in blogPostsArray) {
        BlogPost *blogPost = [[BlogPost alloc] init];
        blogPost.title = [bpDictionary objectForKey:@"title"];
        blogPost.author = [bpDictionary objectForKey:@"author"];
        blogPost.url = [NSURL URLWithString:[bpDictionary objectForKey:@"url"]];
        [self.blogPosts addObject:blogPost];
    }



}

- (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];

    BlogPost *blogpostRow = [self.blogPosts objectAtIndex:indexPath.row];
    cell.textLabel.text = blogpostRow.title;
    cell.detailTextLabel.text = blogpostRow.author;

    return cell;
}

#pragma mark - Table view delegate

- (void)tableView:(UITableView *)tableView didDeselectRowAtIndexPath:(NSIndexPath *)indexPath {

    NSLog(@"Row Selected: %d", indexPath.row);


}

@end

2 Answers

TJ Rogers
TJ Rogers
8,758 Points
TJ Rogers
TJ Rogers
8,758 Points

Ugh... nevermind, I just caught the problem. I used the "didDeselectRow..." method instead of "didSelectRow..."

Steve Weinstock
Steve Weinstock
7,872 Points
Steve Weinstock
Steve Weinstock
7,872 Points

I have been struggling with this problem of the table cells staying highlighted when I pressed them and not registering a checkmark until I selected another cell. Finally the answer. And just in case anyone else has this problem, here is the answer again, but highlighted (it took me awhile looking at TJ's answer to recognize what the difference was:

In both the CameraViewController.m and the EditFriendsViewController.m files, I had inadvertently the DESELECT version of the method rather than the SELECT version, i.e.:

- (void) tableView: (UITableView*)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath is correct

- (void) tableView: (UITableView*)tableView didDeSelectRowAtIndexPath:(NSIndexPath *)indexPath is wrong.

TJ Rogers
TJ Rogers
8,758 Points
TJ Rogers
TJ Rogers
8,758 Points

Today - one year later - I made the same mistake, and tried to Google the problem. This came up (facepalm). Glad it helped you too :)