CustomCell label value does not change - ios

Question

I have created a customCell with UIButton and UILabel
code here:
ItemViewController.h:
#interface ItemViewController : UIViewController<UITableViewDelegate,UITableViewDataSource>
{
NSArray *arr;
IBOutlet ItemCustomCell *itemCell;
}
#property(nonatomic,retain)IBOutlet UITableView *tblItem;
ItemViewController.m
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *simpleTableIdentifier = #"SimpleTableItem";
ItemCustomCell *cell = (ItemCustomCell *) [tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];
if (cell == nil) {
[[NSBundle mainBundle] loadNibNamed:#"ItemCustomCell" owner:self options:nil];
cell = itemCell;
}
cell.btnPlus.tag=indexPath.row;
[cell.btnPlus addTarget:self action:#selector(incrementValue:) forControlEvents:UIControlEventTouchUpInside];
return cell;
}
-(void)incrementValue:(UIButton *)btnAdd
{
NSLog(#"btn%d",btnAdd.tag);
NSIndexPath *indexPath=[NSIndexPath indexPathForRow:btnAdd.tag inSection:0];
ItemCustomCell *cell = (ItemCustomCell*)[tblItem cellForRowAtIndexPath:indexPath];
cell.lblCount.text=[NSString stringWithFormat:#"%d",[cell.lblCount.text intValue]+1];
}
ItemCustomCell.h
#interface ItemCustomCell : UITableViewCell
{
}
#property(nonatomic,strong)IBOutlet UIButton *btnPlus;
#property(nonatomic,assign)IBOutlet UILabel *lblCount;
Default value of label is 1. When I click on the button it displays next value.
When I scroll up or down the tableView label value reset to 1. What I am doing wrong here?

Answer 1

For customCell, you need to specify its reuse identifier and its class name in Xib and load to your cell for reuse:
cell = [[[NSBundle mainBundle] loadNibNamed:#"ItemCustomCell" owner:self options:nil] lastObject];
EDIT
It's better to use IBOutlet and delegate to implement action inside CustomCell then use tag.
//ItemCustomCell.h
#class ItemCustomCell;
#protolcol ItemCustomCellDelegate
-(void) clickPlusButtonInsideCell:(ItemCustomCell *)cell;
#end
#interface ItemCustomCell
#property(weak, nonatomic) id<ItemCustomCellDelegate> delegate;
//Hookup with your view in Xib
#property (weak, nonatomic) IBOutlet UILabel *label;
-(IBACtion)clickPlusBut:(id)sender;
#end
//ItemCustomCell.m
-(IBACtion)clickPlusBut:(id)sender{
[self.delegate clickPlusButtonInsideCell:self];
}
Use
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *simpleTableIdentifier = #"SimpleTableItem";
ItemCustomCell *cell = (ItemCustomCell *) [tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];
if (cell == nil) {
cell = [[[NSBundle mainBundle] loadNibNamed:#"ItemCustomCell" owner:self options:nil] lastObject];
}
cell.delegate = self;
return cell;
}
-(void) clickPlusButtonInsideCell:(ItemCustomCell *)cell{
cell.label.text = #"something";
}

Answer 2

The problem is that you are setting the value of your label from a function associated to your button.
When you scroll your view, making your cell disappearing and re-appearing, your controller rebuild your cell.
So if you don't save the value of your label, you will lose it everytime your cell go out of the screen.
Add something (like an array) to save the value for each of your label. increase the value saved in the same time you are incrementing the value displayed.

Answer 3

You need to store the data seperately, in an array of integers for example. And when you show the cell get the value from the array.
Right now your value is stored in the label, but when you refresh you lose that data and it resets to the default value of 1.
So in your cellForTableRow you set the label text to the value from the array. And in your second method you increase the value stored in the array and then reload data (or change the label manually like you do now.)

Answer 4

You should follow the following approach while using UITableViewCell from nib.
if (cell == nil) {
NSArray *topLevelArray = [[NSBundle mainBundle] loadNibNamed:#"ItemCustomCell" owner:self options:nil];
cell = [topLevelArray objectAtIndex:0];
}

Answer 5

You already have answers about storing the state of the cell outside the cell, because it gets reset when it is recycled. Those are correct.
If the selected state is important - then store it in the object that the cell is representing. That way, if you are configuring the cell based on this object, it will correctly persist through recycling.
If the state is transient, and doesn't need to be stored in the object, you need to store this state somewhere. There are a couple of answers about using an NSArray to store this state. I personally prefer to use an NSDictionary with the indexPath as the key. Since NSIndexPath conforms to NSCopying it can be used as the key for an NSDictionary.

Answer 6

Found a solution, in numberOfSectionInTableView i have to apply a condition based on the state of the tableview and change the label value accordingly. i was using paging so that is the solution.
if someone else is not using paging in a tableview then just set a value before sending a JSON request and apply condition based on the value in numberOfSectionInTableView and it will work.

Answer 7

Your code is displaying next value because your are incrementing value on button click.
cell.lblCount.text=[NSString stringWithFormat:#"%d", [cell.lblCount.text intValue]+1];
And tableView label value are resetting to 1 because new cell creates each time.
You should need to know more about tableview how it work and how to use reusable cell. Have a look this article A Closer Look at Table View Cells