Question

I have seen other posts on this subject, but this seems different.

I am building an iPhone app based on the CoreDataBooks example. In my PatientDetailViewController, the date does not appear in the appropriate row – appearing null when there is obviously data. I have searched in the headers, xib and elsewhere to find why the sample works and mine does not – and I am not making any progress.

Note that dateOfBirth is an attribute of Patient in the model.

In the interface I have

    @class Patient;
    @class EditingViewController;

    #include <UIKit/UIKit.h>

    @interface PatientDetailViewController : UITableViewController {
        Patient *patient;
        NSDateFormatter *dateFormatter;
    }

    @property (nonatomic, retain) Patient *patient;
    @property (nonatomic, retain) NSDateFormatter *dateFormatter;

@end

Here is the code in my tableView: cellForRowAtIndexPath:

    ...
    cell.textLabel.text = @"DOB";
    cell.detailTextLabel.text = [self.dateFormatter stringFromDate:patient.dateOfBirth];

    NSLog(@"the formatted date is %@", [self.dateFormatter stringFromDate:patient.dateOfBirth]);

   NSDate *date = [patient valueForKey:@"dateOfBirth"];
   NSLog(@"the date is %@", date);
    ...

And the output on the console is as follows:

2011-01-02 18:02:27.484 App[3633:207] the formatted date is (null)

2011-01-02 18:02:27.487 App[3633:207] the date is 1993-01-02 17:41:46 -0800

I would appreciate any assistance. Thanks.

Answer 1

Did you allocate it somewhere?

dateFormatter = [[NSDateFormatter alloc] init];

You can place this in viewDidLoad or wherever it is convenient for you. Just make sure that this line is called before you actually use dateFormatter.