I have a issue " index 3 beyond bounds [0 .. 2]' " - ios

Question

#import "MasterTableViewController.h"
#interface MasterTableViewController ()
#end
#implementation MasterTableViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.navigationItem.rightBarButtonItem = self.editButtonItem;
[self.tableView setDelegate:self];
[self.tableView setDataSource:self];
}
- (void)viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
[self.tableView reloadData];
}
#pragma mark - Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return [self isEditing] ? self.wishListItems.count + 1 : self.wishListItems.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"Cell" forIndexPath:indexPath];
WishListItem *item = self.wishListItems[indexPath.row];
if (indexPath.row >= [self.wishListItems count] && self.tableView.isEditing) {
cell.textLabel.text = #"New subject";
cell.imageView.image = nil;
} else {
cell.textLabel.text = item.name;
cell.imageView.image = item.photo;
}
return cell;
}
- (void)setEditing:(BOOL)editing animated:(BOOL)animated {
[super setEditing:editing animated:animated];
if (editing) {
[self.tableView beginUpdates];
[self.tableView insertRowsAtIndexPaths:#[[NSIndexPath indexPathForRow:self.wishListItems.count inSection:0]] withRowAnimation:UITableViewRowAnimationAutomatic];
[self.tableView endUpdates];
} else {
[self.tableView beginUpdates];
[self.tableView deleteRowsAtIndexPaths:#[[NSIndexPath indexPathForRow:self.wishListItems.count inSection:0]] withRowAnimation:UITableViewRowAnimationAutomatic];
[self.tableView endUpdates];
}
}
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {
if (editingStyle == UITableViewCellEditingStyleDelete) {
[self.wishListItems removeObjectAtIndex:indexPath.row];
[tableView deleteRowsAtIndexPaths:#[indexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
[self.tableView reloadData];
} else if (editingStyle == UITableViewCellEditingStyleInsert) {
WishListItem *newItem = [[WishListItem alloc] initWithName:#"New subject" photo:nil price:0.0 andNotes:#"Empty"];
[self.wishListItems insertObject:newItem atIndex:indexPath.row];
[tableView insertRowsAtIndexPaths:#[indexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
[self.tableView reloadData];
}
}
- (UITableViewCellEditingStyle)tableView:(UITableView *)tableView editingStyleForRowAtIndexPath:(NSIndexPath *)indexPath {
if (indexPath.row >= [self.wishListItems count]) {
return UITableViewCellEditingStyleInsert;
} else {
return UITableViewCellEditingStyleDelete;
}
}
//- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
// [self.tableView deselectRowAtIndexPath:indexPath animated:true];
// if (indexPath.row >= self.wishListItems.count && self.editing) {
// [self tableView:tableView commitEditingStyle:UITableViewCellEditingStyleInsert forRowAtIndexPath:indexPath];
// }
//}
#pragma mark - Navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if ([[segue identifier] isEqualToString:#"showDetail"]) {
NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];
WishListItem *item = self.wishListItems[indexPath.row];
DetailViewController *detailViewController = (DetailViewController *)segue.destinationViewController;
detailViewController.item = item;
}
}
#end
I changed "number of row in section" and inserted new row but issue
" index 3 beyond bounds [0 .. 2] ", and I changed "number of row in section"
without increment, appear issue " reason: 'attempt to insert row 3 into section 0, but there are only 3 rows in section 0 after the update' "
I double-check a thousand times and still can not find the problem, help who was able to find what is the problem in the code.

Answer 1

In cellForRowAtIndexPath:, you're accessing your array before you do your bounds check, so it will crash when your table is editing.
Only do the array access after the bounds check:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"Cell" forIndexPath:indexPath];
if (indexPath.row >= [self.wishListItems count] && self.tableView.isEditing) {
cell.textLabel.text = #"New subject";
cell.imageView.image = nil;
} else {
WishListItem *item = self.wishListItems[indexPath.row];
cell.textLabel.text = item.name;
cell.imageView.image = item.photo;
}
return cell;
}