loadNibNamed at Base Class override the instance of Child Class - ios

Question

I have class hierachy with
ParentCell extends UITableViewCell
ChildCell extends ParentCell
ParentCell have separate XIB, In child cell i was creating and adding only one button to one view at ParentCell XIB. but i cant add action for this button. Because even i was creating a instance for ChildCell, that returns the instance of ParentCell
Because i use loadNibNamed to get the XIB with IBOutlet connections.
# initWithStyle method in ParentCell Class
- (id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier
{
self = [super initWithStyle:style reuseIdentifier:reuseIdentifier];
if (self) {
self = [[NSBundle mainBundle] loadNibNamed:#"ParentCell" owner:self options:nil]
[0];
}
return self;
}
# initWithStyle method in ChildCell Class
- (id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier
{
self = [super initWithStyle:style reuseIdentifier:reuseIdentifier];
if (self) {
self.button=[[UIButton alloc] init];
[self.contentView addSubview:button];
}
return self;
}
# View Controller
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"ChildCell ";
ChildCell *cell=[tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil)
{
cell=[[ChildCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
NSLog(#"Cell : %#", cell); //this have instance of ParentCell instead of ChildCell
}
}
Now temporarily solved by this way
# initWithStyle method in ParentCell Class
- (id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier
{
self = [super initWithStyle:style reuseIdentifier:reuseIdentifier];
if (self) {
NSBundle *mainBundle = [NSBundle mainBundle];
NSArray *views = [mainBundle loadNibNamed:#"ParentCell"
owner:self
options:nil];
//Here we are linking the view with appropriate IBOutlet by their tag
self.lblTitle=[views[0] viewWithTag:100];
self.lblContent=[views[0] viewWithTag:200];
}
return self;
}
# initWithStyle method in ChildCell Class
- (id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier
{
self = [super initWithStyle:style reuseIdentifier:reuseIdentifier];
if (self) {
self.button=[[UIButton alloc] init];
[self.contentView addSubview:button];
}
return self;
}
But i don't know this is right approach to follow, or we have some other better approach then this..

Answer 1

You should use the registerNib:forCellReuseIdentifier: method at the viewDidLoad of you UITableView class.
static NSString *parentCellIdentifier = #"parentCellIdentifier";
static NSString *childCellIdentifier = #"childCellIdentifier";
[self.tableView registerNib:[UINib nibWithNibName:#"ParentCell" bundle:nil] forCellReuseIdentifier:parentCellIdentifier];
[self.tableView registerNib:[UINib nibWithNibName:#"ChildCell" bundle:nil] forCellReuseIdentifier:childCellIdentifier];
(Don't forget to set the appropriate ReuseIdentifier at the XIB file)
This is the best practice, and you can get rid of your initWithStyle implementations.