Having trouble with Multiple Selection in UITableview

Question

I've been trying to selection of cell like

Same As Checkbox To select elements from object array

Here is my code. Please guide me.. Thanks in advance

#import <UIKit/UIKit.h>

@interface CheckAllListViewController : UIViewController <UITableViewDataSource,UITableViewDelegate>
{
    IBOutlet UITableView *_myTable;
    NSMutableArray *_myArray;
    NSMutableArray *_selectedArray;
}
@property(nonatomic,retain) UITableView *myTable;
@property(nonatomic,retain)NSMutableArray *myArray;
@property(nonatomic,retain)NSMutableArray *selectedArray;
-(void)checkmarkAll;
-(void)UnChceckAll;

CheckAllListViewController.m

- (void)viewDidLoad
{
    [super viewDidLoad];
    _myArray=[[NSMutableArray alloc]initWithObjects:@"Check All",@"1",@"2",@"3",@"4",@"5",@"6",@"7",@"8",@"9",@"10" ,nil];
    _selectedArray=[[NSMutableArray alloc]init];
    // Do any additional setup after loading the view from its nib.
}

#pragma mark -UITableViewDelegates & Datasource

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
    if (cell.accessoryType == UITableViewCellAccessoryNone) 
    {
        cell.accessoryType = UITableViewCellAccessoryCheckmark;
        [self.selectedArray addObject:[self.myArray objectAtIndex:indexPath.row]];

        //if 'all' row is selected then check all rows
        if([[self.myArray objectAtIndex:indexPath.row] isEqualToString:@"Check All"]) 
        {
            [self checkmarkAll];
        }
    } 
    else if (cell.accessoryType == UITableViewCellAccessoryCheckmark) 
    {
        cell.accessoryType = UITableViewCellAccessoryNone;
        [self.selectedArray removeObject:[self.myArray objectAtIndex:indexPath.row]];

        if([[self.myArray objectAtIndex:indexPath.row] isEqualToString:@"Check All"]) 
        {
            [self UnChceckAll];
            [self.selectedArray removeAllObjects];
        }
        else if([self.selectedArray containsObject:@"Check All"]) 
        {
            [self checkmarkAll];
            [self.selectedArray removeAllObjects];

            cell.accessoryType = UITableViewCellAccessoryNone;
            [self.selectedArray addObject:[self.myArray objectAtIndex:indexPath.row]];
        }
    }
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath   *)indexPath
{
    static NSString *CellIdentifier = @"Cell";

    UITableViewCell *cell = [_myTable dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) 
    {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
    }

    if([self.selectedArray count]) 
    {

        if([self.selectedArray containsObject:[self.myArray objectAtIndex:indexPath.row]] || [self.selectedArray containsObject:@"Check All"]) 
        {
        cell.accessoryType = UITableViewCellAccessoryCheckmark;
        } 
        else 
        {
            cell.accessoryType = UITableViewCellAccessoryNone;
        }

    }
    cell.textLabel.text=[_myArray objectAtIndex:indexPath.row];
    // [self configureCell:cell atIndexPath:indexPath];
    return cell;
}

-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return _myArray.count;
}

-(void)checkmarkAll
{
    for (int i=0;i<[self.myArray count] ; i++)
    {
        NSIndexPath *myIdx=[NSIndexPath indexPathForRow:i inSection:0];
        UITableViewCell *cell=[self.myTable cellForRowAtIndexPath:myIdx];
        cell.accessoryType=UITableViewCellAccessoryCheckmark;
    }
}

-(void)UnChceckAll
{
    for(int i=0;i<[self.myArray count];i++) 
    {

        NSIndexPath *myIndexPath = [NSIndexPath indexPathForRow:i inSection:0];
        UITableViewCell *cell = [self.myTable cellForRowAtIndexPath:myIndexPath];
        cell.accessoryType = UITableViewCellAccessoryNone;
    }
}

I've used this tutorial -http://iphonediscoveries.blogspot.in/2013/10/creating-inclusive-list-in-uitableview.html

I want to achieve : 1 Add an option for the user to be able to select all rows when ‘all’ is selected.

2 When the ‘all’ is checked I want all rows checkmarked, and all checkmarks removed when 'all' is unchecked.

3 When ‘all’ is checked, and all rows are checkmarked, if at that time a row is clicked, then check marks in all other rows should be removed (including ‘all’) and only that row should contain the checkmark. 4 Should not forget Selection After calling and scrolling UITableview

UPDATE

-My Following code gives me check all functionality & Uncheck All Functionality . Lets say I've chosen all row by selecting check all now,If I'd choose any row randomly Should remove tick from current selected element & as well should remove tick from first element i.e @"Check All"
-same for uncheck functionality

Answer 1

Not sure if I get what the problem is, but I would change the checkAll and uncheckAll methods to change the selectedArray and reload the tableview:

-(void)checkmarkAll
{
    self.selectedArray = [NSMutableArray arrayWithArray:self.myArray];
    [self.tableView reloadData];
}