reloading data of a table view is not working - objective-c

Question

im making a tableview with checkboxes. I did implement the checkboxes with UIButtons and i can check and uncheck them without problems. The problem came up when i tried to make a "select/unselect all" button and this is the resultant code:
-(IBAction)select:(id)sender{
if (all==YES) {
all=NO;
}
else {
all=YES;
}
[tblPeticiones reloadData];
}
The problem is that the table doesn't reload the data.
Any idea?
Thanks and regards.
EDIT:
I load de data like this
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
//Datos
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"dd-MM-yyyy"];
NSString *fInicio = [dateFormatter stringFromDate:[(MAP_Gastos_CiberTRIPS *)[m objectAtIndex:indexPath.row] DEP_DATE]];
NSString *loc = [(MAP_Gastos_CiberTRIPS *)[m objectAtIndex:indexPath.row] LOCATION];
NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];
[formatter setNumberStyle:NSNumberFormatterCurrencyStyle];
[formatter setCurrencyCode:#"EUR"];
[formatter setLocale:[NSLocale currentLocale]];
NSString *precio = [formatter stringFromNumber:aux];
//Vista
NSString *MyIdentifier = [NSString stringWithFormat:#"MyIdentifier %i", indexPath.row];
CustomTVC *cell = (CustomTVC *)[tableView dequeueReusableCellWithIdentifier:MyIdentifier];
if (cell == nil) {
cell = [[[CustomTVC alloc] initWithFrame:CGRectZero reuseIdentifier:MyIdentifier] autorelease];
//CheckBox
UIButton *checkButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[checkButton setFrame:CGRectMake(10, 10, 23, 23)];
if (todos==NO) {
[checkButton setBackgroundImage:[[UIImage imageNamed:#"checkNO.png"] stretchableImageWithLeftCapWidth:10.0 topCapHeight:0.0] forState:UIControlStateNormal];
checkButton.tag = 0;
}
else {
[checkButton setBackgroundImage:[[UIImage imageNamed:#"checkSI.png"] str etchableImageWithLeftCapWidth:10.0 topCapHeight:0.0] forState:UIControlStateNormal];
checkButton.tag = 1;
}
[checkButton addTarget:self action:#selector(checkAction:) forControlEvents:UIControlEventTouchUpInside];
[cell addSubview:checkButton];
[cell.contentView addSubview:checkButton];
//fecha
UILabel *label = [[[UILabel alloc] initWithFrame:CGRectMake(40, 0, 70.0,tableView.rowHeight)] autorelease];
[cell addColumn:0];
label.tag = 1;
label.font = [UIFont boldSystemFontOfSize:12.0];
label.text = fInicio;
label.textAlignment = UITextAlignmentLeft;
label.textColor = [UIColor blackColor];
//label.backgroundColor = [UIColor whiteColor];
label.autoresizingMask = UIViewAutoresizingNone | UIViewAutoresizingFlexibleHeight;
[cell.contentView addSubview:label];
if (indexPath.row % 2 == 0){
label.backgroundColor = [UIColor colorWithRed:233.0/255.0
green:233.0/255.0
blue:233.0/255.0
alpha:1.0];
} else {
label.backgroundColor = [UIColor clearColor];
}
//localización
label = [[[UILabel alloc] initWithFrame:CGRectMake(115, 0, 75.0,tableView.rowHeight)] autorelease];
[cell addColumn:180];
label.tag = 2;
label.font = [UIFont boldSystemFontOfSize:12.0];
label.text = loc;
label.textAlignment = UITextAlignmentLeft;
label.textColor = [UIColor blackColor];
//label.backgroundColor = [UIColor whiteColor];
label.autoresizingMask = UIViewAutoresizingNone | UIViewAutoresizingFlexibleHeight;
[cell.contentView addSubview:label];
if (indexPath.row % 2 == 0){
label.backgroundColor = [UIColor colorWithRed:233.0/255.0
green:233.0/255.0
blue:233.0/255.0
alpha:1.0];
} else {
label.backgroundColor = [UIColor clearColor];
}
}
return cell;
}

Answer 1

Debug the problem
Check datasource methods of tableView whether they are being called or not after reload?

Answer 2

You should store which rows are checked in an array. Then check this array when you load / reload the tableview (in cellForRowAtIndex) to see if the row should be checked.
Then if you want to select all or none, just delete or add them to the array and reload the tableview.
If you need help implementing this, let me know.

Answer 3

i found the problem. This is the working code:
-(IBAction)select:(id)sender{
if (all==YES) {
all=NO;
[btnSelAll setBackgroundImage:[[UIImage imageNamed:#"checkSI.png"] stretchableImageWithLeftCapWidth:10.0 topCapHeight:0.0] forState:UIControlStateNormal];
}else {
all=YES;
[btnSelAll setBackgroundImage:[[UIImage imageNamed:#"checkNO.png"] stretchableImageWithLeftCapWidth:10.0 topCapHeight:0.0] forState:UIControlStateNormal];
}
NSMutableArray *arrIndex = [NSMutableArray new];
for(int i=0;i<[m count];i++) {
[arrIndex addObject:[NSIndexPath indexPathForRow:i inSection:0]];
}
[self.tblPeticiones beginUpdates];
[tblPeticiones reloadRowsAtIndexPaths:arrIndex withRowAnimation:UITableViewRowAnimationNone];
[self.tblPeticiones endUpdates];
[tblPeticiones reloadData];
}

Answer 4

Some comments about your code:
There seems to be global variable called all, whose value you toggle, when button is pressed. However inside cellForRowAtIndexPath you check value of another global variable called todos. Is there some connection between these variables?
You change checkbox background image only, when you create a new cell. Since cells are recycled, you need to move this code outside if (cell == nil) i.e. afterwards, where you are customizing a recycled cell
You should only check whether if (todos) and if (!todos), don't compare to values like YES or NO. Also easiest way to toggle a boolean is todos = !todos :)