Inserting items in UITableView crashes application - ios

I'm making an application with a tableview list of contacts that can be reached via a tab-controller at the bottom.
I copied (literally copy/pasted) from the example Master Detail Application and tried to make sure all storyboard references lined up.
#import "ContactsTableViewController.h"
#import "ContactViewController.h"
#interface ContactsTableViewController () {
NSMutableArray *_objects;
}
#end
#implementation ContactsTableViewController
- (void)awakeFromNib
{
if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPad) {
self.clearsSelectionOnViewWillAppear = NO;
self.preferredContentSize = CGSizeMake(320.0, 600.0);
}
[super awakeFromNib];
// [self.tableView setDelegate:self]; // From (unsuccesfully) trying https://stackoverflow.com/questions/16311393/how-to-insert-items-to-a-uitableview-when-a-uibutton-is-clicked-in-ios
// [self.tableView setDataSource:self];
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
self.navigationItem.leftBarButtonItem = self.editButtonItem;
UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:#selector(insertNewObject:)];
self.navigationItem.rightBarButtonItem = addButton;
self.contactViewController = (ContactViewController *)[[self.splitViewController.viewControllers lastObject] topViewController];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (void)insertNewObject:(id)sender
{
if (!_objects) {
_objects = [[NSMutableArray alloc] init];
}
[_objects insertObject:[NSDate date] atIndex:0];
NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:0];
[self.tableView insertRowsAtIndexPaths:#[indexPath] withRowAnimation:UITableViewRowAnimationAutomatic]; // Crashes here
}
#pragma mark - Table View
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return _objects.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"Cell" forIndexPath:indexPath]; // Crashes here
NSDate *object = _objects[indexPath.row];
cell.textLabel.text = [object description];
return cell;
}
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
// Return NO if you do not want the specified item to be editable.
return YES;
}
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
if (editingStyle == UITableViewCellEditingStyleDelete) {
[_objects removeObjectAtIndex:indexPath.row];
[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;
}
*/
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPad) {
NSDate *object = _objects[indexPath.row];
self.contactViewController.detailItem = object;
}
}
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if ([[segue identifier] isEqualToString:#"showDetail"]) {
NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];
NSDate *object = _objects[indexPath.row];
[[segue destinationViewController] setDetailItem:object];
}
}
#end
It crashes on the first line in CellRowAtIndexPath. Since I was having trouble I also took the advice in How to insert items to a UITableView when a UIButton is clicked in iOS but it didn't solve my problem.
This is just incredibly frustrating, because as far as I can tell my code is (except for names) exactly the same as the example application.
edit: Exception message is
'NSInternalInconsistencyException', reason: 'unable to dequeue a cell with identifier Cell - must register a nib or a class for the identifier or connect a prototype cell in a storyboard'

Alex - When using storyboards and the new prototype cell feature in xCode, you have to set an identifier value in Interface Builder whose value should match what is in your code.
So notice you have this line:
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"Cell" forIndexPath:indexPath];
In this case, your cell identifier is "Cell"
Can you confirm that in Interface Builder/Storyboard, your table view cell's identifier is set to the same?
As an example, here's a screenshot from a sample app I was building (Notice my Indentifier field on the right):

I would recommend this
-(void)ViewDidLoad{
[tableView registerClass:[MyCell class] forCellReuseIdentifier:#"Cell"];
}
- (void)insertNewObject:(id)sender
{
if (!_objects) {
_objects = [[NSMutableArray alloc] init];
}
[_objects insertObject:[NSDate date] atIndex:0];
[tableView reloadData]; //this will trigger cellForRowAtIndexPath again with the updated array
}
and would you please post your error.

You should not use [self.tableView insertRowsAtIndexPaths: withRowAnimation:];. Instead of this you should call [talbeView reloadData] method.

Related

Application crashing after an attempt to delete row from UITableView

- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {
if (editingStyle == UITableViewCellEditingStyleDelete) {
[self.effectsTableView beginUpdates];
Effect *effectToBeDeleted =self.effectsArray[indexPath.row];
[self deleteEffectWithName:effectToBeDeleted.name];
[self.effectsTableView deleteRowsAtIndexPaths:[NSArray arrayWithObjects:indexPath, nil] withRowAnimation:UITableViewRowAnimationTop];
[self.effectsArray removeObjectAtIndex:indexPath.row];
[self.effectsTableView endUpdates];
}
}
The above function should in theory delete the rows as they are slided and the delete button is pressed. However the row does not delete instead is visible even after the
[self.effectsTableView deleteRowsAtIndexPaths:[NSArray arrayWithObjects:indexPath, nil] withRowAnimation:UITableViewRowAnimationTop];
is called. And after the user scrolls to the bottom of the UITableView, while loading the last row, the app obviously crashes with "*** -[__NSArrayM objectAtIndex:]: index 9 beyond bounds [0 .. 8]" error since one of the objects has been deleted from the array.
the cellForRowAtIndexPath is as follows:
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
if (!self.effectsArray)
{
[self loadEffectsInArray];
}
static NSString *cellIdentifier = #"EffectsCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellIdentifier];
}
Effect *effectCellEffect = [self.effectsArray objectAtIndex:indexPath.row];
NSString *effectCellText = effectCellEffect.name;
[cell.textLabel setText:effectCellText];
cell.textLabel.font = [UIFont systemFontOfSize:[UIFont labelFontSize]];
return cell;
}
Below is the entire .m file for better context:
#import "EffectsManagementTableViewController.h"
#import "Effect+Manage.h"
#import "VLOGAppDelegate.h"
#import "AddEffectViewController.h"
#import "EffectFilterProperty+Manage.h"
#import "Effect.h"
#interface EffectsManagementTableViewController ()
#property (strong, nonatomic) IBOutlet UITableView *effectsTableView;
#property (nonatomic, retain) NSManagedObjectContext *managedObjectContext;
#property (nonatomic, strong) NSMutableArray *effectsArray;
#property (nonatomic, strong) NSString *currSelectedRowTitle;
#end
#implementation EffectsManagementTableViewController
-(NSString *)currSelectedRowTitle
{
if(!_currSelectedRowTitle)
{
_currSelectedRowTitle = #"";
}
return _currSelectedRowTitle;
}
- (id)initWithStyle:(UITableViewStyle)style
{
self = [super initWithStyle:style];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Uncomment the following line to preserve selection between presentations.
// self.clearsSelectionOnViewWillAppear = NO;
// Uncomment the following line to display an Edit button in the navigation bar for this view controller.
// self.navigationItem.rightBarButtonItem = self.editButtonItem;
VLOGAppDelegate* appDelegate = [UIApplication sharedApplication].delegate;
self.managedObjectContext = appDelegate.managedObjectContext;
self.effectsTableView.dataSource = self;
self.effectsTableView.delegate = self;
}
-(void)viewWillAppear:(BOOL)animated
{
[self loadEffectsInArray];
[self.effectsTableView reloadData];
[self.effectsTableView setNeedsDisplay];
[self.effectsTableView setNeedsLayout];
}
- (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
{
if (!self.effectsArray)
{
[self loadEffectsInArray];
}
return [self.effectsArray count];
}
//4
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
if (!self.effectsArray)
{
[self loadEffectsInArray];
}
static NSString *cellIdentifier = #"EffectsCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellIdentifier];
}
//6
Effect *effectCellEffect = [self.effectsArray objectAtIndex:indexPath.row];
NSString *effectCellText = effectCellEffect.name;
//7
[cell.textLabel setText:effectCellText];
//[cell.detailTextLabel setText:#"5 stars!"];
cell.textLabel.font = [UIFont systemFontOfSize:[UIFont labelFontSize]];
//cell.backgroundColor = [UIColor blackColor];
//cell.textLabel.textColor = [UIColor whiteColor];
//cell.detailTextLabel.textColor = [UIColor grayColor];
//cell.textLabel.highlightedTextColor = self.effectsTableView.tintColor;
return cell;
}
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath {
// Return YES if you 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) {
[self.effectsTableView beginUpdates];
Effect *effectToBeDeleted =self.effectsArray[indexPath.row];
[self deleteEffectWithName:effectToBeDeleted.name];
[self.effectsTableView deleteRowsAtIndexPaths:[NSArray arrayWithObjects:indexPath, nil] withRowAnimation:UITableViewRowAnimationTop];
[self.effectsArray removeObjectAtIndex:indexPath.row];
//[self loadEffectsInArray];
[self.effectsTableView endUpdates];
//[self.effectsTableView reloadData];
//[self.effectsTableView setNeedsLayout];
//[self.effectsTableView setNeedsDisplay];
}
}
-(void)deleteEffectWithName:(NSString *)effectName
{
NSArray *efpForEffectToBeDeleted = [EffectFilterProperty getEffectFilterPropertiesForEffectName:effectName forImmediateEngagement:NO forManagedObjectContext:self.managedObjectContext];
Effect *effectToBeDeleted = [Effect getEffectWithName:effectName forManagedObjectContext:self.managedObjectContext];
for (int i = 0; i < efpForEffectToBeDeleted.count; i++)
{
EffectFilterProperty *currEFP = efpForEffectToBeDeleted[i];
currEFP.relatedEffect = nil;
currEFP.relatedFilterProperty = nil;
[self.managedObjectContext deleteObject:currEFP];
}
[self.managedObjectContext deleteObject:effectToBeDeleted];
NSError *err = nil;
[self.managedObjectContext save:&err];
if (err != nil) {
//Problem while saving
}
}
-(void)loadEffectsInArray
{
self.effectsArray = [[Effect getAllEffectsForManagedObjectContext:_managedObjectContext] mutableCopy];
}
-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
Effect *effectCellEffect = [self.effectsArray objectAtIndex:indexPath.row];
self.currSelectedRowTitle = effectCellEffect.name;
[self performSegueWithIdentifier:#"PushedByTableView" sender:self];
}
/*
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:<##"reuseIdentifier"#> forIndexPath:indexPath];
// Configure the cell...
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 - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
// Make sure your segue name in storyboard is the same as this line
if ([[segue identifier] isEqualToString:#"PushedByTableView"])
{
AddEffectViewController *destinationViewController = segue.destinationViewController;
NSString *selectedRowText = self.currSelectedRowTitle;
destinationViewController.effectToManage = [Effect getEffectWithName:selectedRowText forManagedObjectContext:self.managedObjectContext];
}
}
#end
What am I doing wrong here?
where are you beginning your updates, please add
[self.effectsTableView beginUpdates];
before deleting your row and no need of reloading the table when you are writing the begin updates and end updates.
Please don't remove the object from array before deleting the row.
IT'S WORKING
At end of your commitEditingStyle method add this line this will help you
[TableViewForFirstView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
try this code to add beginUpdatesmethod before delete called
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {
if (editingStyle == UITableViewCellEditingStyleDelete) {
[self.effectsTableView beginUpdates];
Effect *effectToBeDeleted =self.effectsArray[indexPath.row];
[self deleteEffectWithName:effectToBeDeleted.name];
[self.effectsTableView deleteRowsAtIndexPaths:[NSArray arrayWithObjects:indexPath, nil] withRowAnimation:UITableViewRowAnimationTop];
[self.effectsArray removeObjectAtIndex:indexPath.row];
[self loadEffectsInArray];
[self.effectsTableView endUpdates];
}
Try this code:
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {
if (editingStyle == UITableViewCellEditingStyleDelete) {
Effect *effectToBeDeleted =[self.effectsArray objectAtIndex:indexPath.row];
[self deleteEffectWithName:effectToBeDeleted.name];
[self.effectsArray removeObjectAtIndex:indexPath.row];
[self loadEffectsInArray];
[self.effectsTableView reloadData];
}
As this message, it's crash for reason out of bound, so try check the array index before assign:
Effect *effectToBeDeleted = self.effectsArray > indexPath.row ? self.effectsArray[indexPath.row] : nil;
And
if(self.effectsArray.count > indexpath.row)
[self.effectsArray removeObjectAtIndex:indexPath.row];
else
NSlog("out of bound");

How do I change an array and make it show the changes in the UITableView?

To see items in my tableview, I load them from an array, but when I arrange the table, the changes don't stay. It works at first, but when I click on one of the cells it loads the data from the original order.
This is my tableview controller. I got almost all of the code from this apple developer tutorial:
https://developer.apple.com/library/ios/referencelibrary/GettingStarted/RoadMapiOS/ThirdTutorial.html#//apple_ref/doc/uid/TP40011343-CH10-SW1
#import "NoteViewController.h"
#import "Note.h"
#import "NewNoteViewController.h"
#interface NoteViewController ()
#property NSMutableArray *notes;
#end
#implementation NoteViewController
- (IBAction)unwindToList:(UIStoryboardSegue *)segue
{
NewNoteViewController *source = [segue sourceViewController];
Note *notee = source.note;
if (notee != nil)
{
[self.notes addObject:notee];
[self.tableView reloadData];
}
}
/*
- (void)loadInitialData
{
Note *item1 = [[Note alloc] init];
item1.itemName = #"Note 1";
[self.notes addObject:item1];
}
*/
- (id)initWithStyle:(UITableViewStyle)style
{
self = [super initWithStyle:style];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
self.navigationItem.leftBarButtonItem = self.editButtonItem;
self.notes = [[NSMutableArray alloc] init];
//[self loadInitialData];
// Uncomment the following line to preserve selection between presentations.
// self.clearsSelectionOnViewWillAppear = NO;
// Uncomment the following line to display an Edit button in the navigation bar for this view controller.
// self.navigationItem.rightBarButtonItem = self.editButtonItem;
}
- (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.notes count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"NotePrototypeCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
Note *note = [self.notes objectAtIndex:indexPath.row];
cell.textLabel.text = note.itemName;
// Configure the cell...
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
[self.notes removeObjectAtIndex:indexPath.row];
[tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath]withRowAnimation:UITableViewRowAnimationLeft];
}
}
// 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 - Navigation
// In a story board-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
// Get the new view controller using [segue destinationViewController].
// Pass the selected object to the new view controller.
}
*/
#pragma mark - Table view delegate
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
[tableView deselectRowAtIndexPath:indexPath animated:NO];
//Note *tappedItem = [self.notes objectAtIndex:indexPath.row];
[tableView reloadRowsAtIndexPaths:#[indexPath]withRowAnimation:UITableViewRowAnimationNone];
}
#end
By uncommenting - (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath You have enabled moving rows. You need to implement that method to swap the items in your notes array. Like:
id *note = [self.notes objectAtIndex:sourceIndexPath.row];
[self.notes removeObjectAtIndex:fromIndexPath.row];
[self.notes insertObject:note atIndex:toIndexPath.row];

Going through Apple's ToDoList app tutorial, item tapping doesn't add "completed" checkmark properly.

When I tap an item, it doesn't seem to register and add a checkmark on the right. When I tap a subsequent item, it shows a checkmark next to the one I tapped previously, but not for the one I just tapped, and so on, always remaining one action behind.
XYZToDoListViewController.m:
//
// XYZToDoListViewController.m
// ToDoList
//
// Created by Andrew Ghobrial on 2/15/14.
//
//
#import "XYZToDoListViewController.h"
#import "XYZToDoItem.h"
#interface XYZToDoListViewController ()
#property NSMutableArray *toDoItems;
#end
#implementation XYZToDoListViewController
- (void)loadInitialData {
XYZToDoItem *item1 = [[XYZToDoItem alloc] init];
item1.itemName = #"Buy milk";
[self.toDoItems addObject:item1];
XYZToDoItem *item2 = [[XYZToDoItem alloc] init];
item2.itemName = #"Buy eggs";
[self.toDoItems addObject:item2];
XYZToDoItem *item3 = [[XYZToDoItem alloc] init];
item3.itemName = #"Read a book";
[self.toDoItems addObject:item3];
}
- (IBAction)unwindToList:(UIStoryboardSegue *)segue
{
}
- (id)initWithStyle:(UITableViewStyle)style
{
self = [super initWithStyle:style];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
self.toDoItems = [[NSMutableArray alloc] init];
[self loadInitialData];
// Uncomment the following line to preserve selection between presentations.
// self.clearsSelectionOnViewWillAppear = NO;
// Uncomment the following line to display an Edit button in the navigation bar for this view controller.
// self.navigationItem.rightBarButtonItem = self.editButtonItem;
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#pragma mark - Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
// Return the number of rows in the section.
return [self.toDoItems count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"ListPrototypeCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
XYZToDoItem *toDoItem = [self.toDoItems objectAtIndex:indexPath.row];
cell.textLabel.text = toDoItem.itemName;
if (toDoItem.completed) {
cell.accessoryType = UITableViewCellAccessoryCheckmark;
} else {
cell.accessoryType = UITableViewCellAccessoryNone;
}
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 - Navigation
// In a story board-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
// Get the new view controller using [segue destinationViewController].
// Pass the selected object to the new view controller.
}
*/
#pragma mark - Table view delegate
- (void)tableView:(UITableView *)tableView didDeselectRowAtIndexPath:(NSIndexPath *)indexPath
{
[tableView deselectRowAtIndexPath:indexPath animated:NO];
XYZToDoItem *tappedItem = [self.toDoItems objectAtIndex:indexPath.row];
tappedItem.completed = !tappedItem.completed;
[tableView reloadRowsAtIndexPaths:#[indexPath]withRowAnimation:UITableViewRowAnimationNone];
}
#end
- (void)tableView:(UITableView *)tableView didDeselectRowAtIndexPath:(NSIndexPath *)indexPath
should be
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
Notice you have Deselect but want Select

UITableview keeps old cells after reloadData

I have a view with a tabBar at the bottom and a tableview. When a barButtonItem is pressed, the array that holds the data for the tableview changes.
With NSLogs, it is clear that the array is really changing, as the [NSArray count] displays different values. However, when I use [UITableview reloadData], the cells stay the same.
If I scroll a up a bit however and then scroll back down, whatever went offscreen gets updating. I'm guessing this is because when it goes offscreen it is dequeued and when it comes back it is redrawn with the new data. Is there a way to just have it redraw everything?
#import "TableViewController.h"
#interface TableViewController ()
#end
#implementation TableViewController
#synthesize listBar,selectedTab , linkTableView, barButton5, barButton4, barButton3, barButton2, barButton1, Lists, imageID, titleID, linkID, cells;
- (void)viewDidLoad
{
[super viewDidLoad];
linkTableView = [[UITableView alloc] init];
Lists = [[NSArray alloc] init];
imageID = [[NSMutableArray alloc] init];
titleID = [[NSMutableArray alloc] init];
linkID = [[NSMutableArray alloc] init];
linkTableView.delegate = self;
linkTableView.dataSource = self;
}
-(void)viewWillAppear:(BOOL)animated{
NSArray *barItems = [[NSArray alloc] initWithObjects:barButton1, barButton2, barButton3, barButton4, barButton5, nil];
listBar.selectedItem = [barItems objectAtIndex:selectedTab];
//when view will appear load data dependent on selectedTab
[self performSelector:#selector(updateTable)];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
-(void)tabBar:(UITabBar *)tabBar didSelectItem:(UITabBarItem *)item{
selectedTab = item.tag;
[self performSelector:#selector(updateTable)];
}
-(void)updateTable{
[imageID removeAllObjects];
[titleID removeAllObjects];
[linkID removeAllObjects];
//load from the xml file
RXMLElement *rxml = [RXMLElement elementFromXMLFile:#"Lists.xml"];
//makes an array from the list children
Lists = [rxml children:#"List"];
cells = [[Lists objectAtIndex:selectedTab] children:#"Cell"];
[rxml iterateElements:cells usingBlock:^(RXMLElement *cellElement) {
[imageID addObject:[cellElement child:#"ImageName"]];
[titleID addObject:[cellElement child:#"CellText" ]];
[linkID addObject:[cellElement child:#"Link" ]];
}];
NSLog(#"Count is %i", [cells count]);
[linkTableView reloadData];
}
#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 [cells count];
}
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{
return 60;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"LinkCell";
linkCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
if (cell == nil) {
cell = [[linkCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
// Configure the cell...
NSString *imageName = [NSString stringWithFormat:#"%#", [imageID objectAtIndex:indexPath.row]];
cell.image.image = [UIImage imageNamed:imageName];
NSString *labelText = [NSString stringWithFormat:#"%#", [titleID objectAtIndex:indexPath.row]];
cell.linkCellLabel.text = labelText;
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
remove this line from your code:
linkTableView = [[UITableView alloc] init];
or any other initializers for your uitableview
and use this code to update the Sections
[self.tableView beginUpdates];
NSMutableIndexSet* index = [[NSMutableIndexSet alloc]init];
[index addIndex:0];
[self.tableView reloadSections:index withRowAnimation:UITableViewRowAnimationAutomatic];
[self.tableView endUpdates];

Couldn't launch self.editing mode when press Edit button in TableView

I'm trying to create an editable table in iPhone App. I have two questions.
When I press the Edit button and thus enter the editing mode, I cannot delete a row.
If there's a way to add a "add new cell" function instead of the way I did in my code? (I added a addButtonAction method.)
Here's my .h
#import <UIKit/UIKit.h>
#interface FirstViewController : UITableViewController <UITableViewDelegate, UITableViewDataSource>
{
UITableView *table;
NSMutableArray *tableDataSource;
}
-(IBAction)addButtonAction:(id)sender;
#end
Here's the .m
#import "FirstViewController.h"
#implementation FirstViewController
- (IBAction)addButtonAction:(id)sender
{
if(tableDataSource != nil)
{
[tableDataSource addObject:#"New City"];
}
[table reloadData];
}
- (id)initWithStyle:(UITableViewStyle)style
{
self = [super initWithStyle:style];
if (self) {
// Custom initialization
}
return self;
}
- (void)didReceiveMemoryWarning
{
// Releases the view if it doesn't have a superview.
[super didReceiveMemoryWarning];
// Release any cached data, images, etc that aren't in use.
}
#pragma mark - View lifecycle
- (void)viewDidLoad
{
[super viewDidLoad];
tableDataSource = [[NSMutableArray alloc]init];
[tableDataSource addObjectsFromArray:[NSArray arrayWithObjects: #"Canada", #"United States", #"Australia", #"United Kingdom", nil]];
table = [[UITableView alloc] initWithFrame:CGRectMake(0, 0, 320, 367) style:UITableViewStyleGrouped];
[table setDataSource:self];
[table setDelegate:self];
[self.view addSubview:table];
[[self navigationItem] setLeftBarButtonItem:[self editButtonItem]];
UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd
target:self
action:#selector(addButtonAction:)];
[[self navigationItem] setRightBarButtonItem:addButton];
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}
- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
[[self tableView] reloadData];
}
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
}
- (void)viewWillDisappear:(BOOL)animated
{
[super viewWillDisappear:animated];
}
- (void)viewDidDisappear:(BOOL)animated
{
[super viewDidDisappear:animated];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
// Return YES for supported orientations
return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
#pragma mark - Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [tableDataSource count];
}
- (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];
}
// Configure the cell...
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
cell.textLabel.text = [tableDataSource objectAtIndex:indexPath.row];
return cell;
}
#pragma - Enable/Disable Edit Button
- (void)setEditing:(BOOL)editing animated:(BOOL)animated
{
[super setEditing:editing
animated:animated];
[table setEditing:editing animated:animated];
}
#pragma - Editing Style
// Override to support conditional editing of the table view.
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
return YES;
}
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
if (editingStyle == UITableViewCellEditingStyleDelete)
{
// Delete the row from the data source
[tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject: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
}
}
#pragma - Can Move Row
// Override to support rearranging the table view.
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath
{
NSString *item = [tableDataSource objectAtIndex:fromIndexPath.row];
[tableDataSource removeObject:item];
[tableDataSource insertObject:item atIndex:toIndexPath.row];
}
// Override to support conditional rearranging of the table view.
- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath
{
return YES;
}
#pragma mark - Table Title
- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section
{
if(section == 0)
{
return #"City";
}
else
{
return #"Nothing here";
}
}
#pragma mark - Table view delegate
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
if (indexPath.section == 0)
{
//TBD....
}
[tableView deselectRowAtIndexPath:indexPath animated:YES];
}
#end
Make sure when you delete row from tableView also to delete the object from NSArray.
This addButton I thik will work but this
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
make like this:
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
Just remove if statament...
Hope I understand your question ant this help.

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