iPhone Subclassing view controller and IBOutlet UITableView

Question

I have the following problem. I've created a ViewController pretty much like the above

@interface MyViewController : UIViewController {
    IBOutlet UITableView *myTableView;
}

@property (nonatomic, retain) IBOutlet UITableView *myTableView;

I've linked myTableView on the Interface Builder to the matching nib's UITableView. and I've subclassed MyViewController to create YourViewController as so:

@interface YourViewController : MyViewController {

}

And then I load from a TabBarController the YourViewController on a tab item. Although I can see that MyViewController is indeed invoked at the end, no table view is displayed on the emulator.

I've tried debugging the MyViewController and it appears the the IBOutlet is nil.

Why is that?

Answer 1

I have encountered major issues with inheritance and IBOutlets and IBAction. I advise you to avoid that, and create shared stuff in another way.

I was hit hard by bugs when getting memory warnings for instance. Outlets and actions didn't get reconnected properly when they were defined in base class vs derived class.

Answer 2

Probably MyViewController's nib file is not loaded at all. Are you using for YourViewController a specific nib file? and in which way are you creating YourViewController.

Can you also try to define an "awakeFromNib" method in YourViewController and then from it call [super awakeFromNib] ?

However to understand your issue you must clearly explain how you load objects and if and where you use Nibs?

Answer 3

If you add it dynamically using code then only it will work. Not using Nib.

Answer 4

the UITableView (ie. your myTableView) needs delegates for data source and and its control. And your controller needs a link to the Table view in the xib.

1. declare table delegate protocols in the interface section of your controller.

2. using IB, link the TableView in your xib to owners file:delegates.

3. using IB, link the file owner myTableView to the tableView in the xib.

I hope it will help.

Answer 5

Assuming that you have your whole navigation stack in MainWindow.xib

• Open MainWindow.xib
• Select YourViewController (Or whatever your controller that is subclassing UITableViewController is called)
• Select Attributes Inspector
• Ensure that the 'NIB Name' property has your correct YourViewController (Or whatever the name) selected

I had this exact same issue, this solved it for me.