NSUserDefault not loading in table view - ios

Question

I have a main view with a button that when pressed it adds the url from the web view(like a bookmark) to a table view. The only problem is that its not loading. ive been at it for hours now but cant figure it out. I think i am loading the data in the table view wrong but not quiet sure.
This is the MainViewController.m
- (IBAction)bookmark:(id)sender {
UIActionSheet *actionSheet =
[[UIActionSheet alloc] initWithTitle:[[[[self webView] request] URL]
absoluteString] delegate:nil cancelButtonTitle:#"Cancel"
destructiveButtonTitle:nil otherButtonTitles:#"Add", nil];
[actionSheet showInView:self.view];
}
- (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex {
if (buttonIndex == 0) {
NSMutableArray *bookmarks = [[[NSUserDefaults standardUserDefaults]
arrayForKey:#"Bookmarks"] mutableCopy];
if (!bookmarks) {
bookmarks = [[NSMutableArray alloc] init];
}
[bookmarks addObject:[[[[self webView]request] URL] absoluteString]];
[[NSUserDefaults standardUserDefaults] setObject:bookmarks
forKey:#"Bookmarks"];
}
}
This is BookmarksViewController.m
- (void)viewDidLoad {
[super viewDidLoad];
NSLog(#"%#", bookmarks);
bookmarks = [[[NSUserDefaults standardUserDefaults]
arrayForKey:#"Bookmarks"] mutableCopy];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
[[NSUserDefaults standardUserDefaults] setObject:bookmarks forKey:#"Bookmarks"];
cell.textLabel.text = [self.bookmarks objectAtIndex:indexPath.row];
return cell;
}

Answer 1

When your app is first run there is nothing set for the Bookmarks key in NSUserDefaults. So the line:
bookmarks = [[[NSUserDefaults standardUserDefaults]
arrayForKey:#"Bookmarks"] mutableCopy];
in viewDidLoad leaves bookmarks set to nil.
In your action sheet handler you actually deal with this properly.
And one other big problem is the call to:
[[NSUserDefaults standardUserDefaults] setObject:bookmarks forKey:#"Bookmarks"];
in your cellForRowAtIndexPath... method. Why do you update NSUserDefaults every time a cell is needed? Don't do this.

Answer 2

The command [tableView dequeueReusableCellWithIdentifier:CellIdentifier] does NOT always return a cell. It only returns a cell if there is a cell in the reusable-cell queue.
So your method should be:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
[[NSUserDefaults standardUserDefaults] setObject:bookmarks forKey:#"Bookmarks"];
cell.textLabel.text = [self.bookmarks objectAtIndex:indexPath.row];
return cell;
}