user1697845 user1697845 - 6 months ago 36
iOS Question

Creating a UITableView Programmatically

I have an application in Xcode 4.6 which uses storyboards. I added a UITableView to a view controller class, which worked as expected. However, when I tried deleting the UITableView in the storyboard and adding it back into the same class programmatically, I ran into two specific problems:

1) Although I set the UITableViewCell type to be of type subtitle, the detail label no longer appears.

2) The segue that should occur when I select a cell does not occur, and prepare segue is not even being called, indicating that no message is being sent to the table view when a cell is selected.

Here is the relevant code:

@interface StatsTableViewController () <UITableViewDataSource, UITableViewDelegate>
@property (strong, nonatomic) UITableView *tableView;

@end

@implementation StatsTableViewController

-(UITableView *)makeTableView
{
CGFloat x = 0;
CGFloat y = 50;
CGFloat width = self.view.frame.size.width;
CGFloat height = self.view.frame.size.height - 50;
CGRect tableFrame = CGRectMake(x, y, width, height);

UITableView *tableView = [[UITableView alloc]initWithFrame:tableFrame style:UITableViewStylePlain];

tableView.rowHeight = 45;
tableView.sectionFooterHeight = 22;
tableView.sectionHeaderHeight = 22;
tableView.scrollEnabled = YES;
tableView.showsVerticalScrollIndicator = YES;
tableView.userInteractionEnabled = YES;
tableView.bounces = YES;

tableView.delegate = self;
tableView.dataSource = self;

return tableView;
}

- (void)viewDidLoad
{
[super viewDidLoad];
self.tableView = [self makeTableView];
[self.tableView registerClass:[UITableViewCell class] forCellReuseIdentifier:@"newFriendCell"];
[self.view addSubview:self.tableView];
}

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

if (cell == nil)
{
cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier];
}

Friend *friend = [self.fetchedResultsController objectAtIndexPath:indexPath];

**//THIS DATA APPEARS**
cell.textLabel.text = friend.name;
cell.textLabel.font = [cell.textLabel.font fontWithSize:20];
cell.imageView.image = [UIImage imageNamed:@"icon57x57"];

**//THIS DATA DOES NOT APPEAR**
cell.detailTextLabel.text = [NSString stringWithFormat:@"%i Games", friend.gameCount];
cell.detailTextLabel.textColor = [UIColor lightGrayColor];

return cell;
}

-(void)tableView:(UITableView *)tableView didDeselectRowAtIndexPath:(NSIndexPath *)indexPath
{
[self performSegueWithIdentifier:@"detailsView" sender:self];
}

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
//I set the segue identifier in the interface builder
if ([segue.identifier isEqualToString:@"detailsView"])
{

NSLog(@"segue"); //check to see if method is called, it is NOT called upon cell touch

NSIndexPath *indexPath = [self.tableView indexPathForCell:sender];
///more code to prepare next view controller....
}
}


I am not sure what I am forgetting to do so that I can solve these two issues. Any help is appreciated.

Answer

When you register a class, and use dequeueReusableCellWithIdentifier:forIndexPath:, the dequeue method is guaranteed to return a cell, so your if (cell == nil) clause is never entered. So, just do it the old way, don't register the class, and use dequeueReusableCellWithIdentifier:

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

    if (cell == nil) {
        cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier];
    }
//etc.
return cell;
}

As for the segue, it can't be called because you can't make a segue to a table that you've created in code, not in IB. Again, go back to the old way and use tableView:didSelectRowAtIndexPath: which will be called when you select a cell. Instantiate your detail controller there and do the trasition in code.

After edit:

I didn't see your added code there. You've implemented didDeselectRowAtIndexPath rather than didSelectRowAtIndexPath. If you change that, your segue should work.