Unable to set text field on UILabel

Question

I have created UITableCellView class called NoteCell. The header defines the following:

#import <UIKit/UIKit.h>
#import "Note.h"

@interface NoteCell : UITableViewCell {
    Note *note;
    UILabel *noteTextLabel;  
}

@property (nonatomic, retain) UILabel *noteTextLabel;

- (Note *)note;
- (void)setNote:(Note *)newNote; 

@end

In the implementation I have the following code for the setNote: method:

- (void)setNote:(Note *)newNote {
    note = newNote;
    NSLog(@"Text Value of Note = %@", newNote.noteText);
    self.noteTextLabel.text = newNote.noteText;
    NSLog(@"Text Value of Note Text Label = %@", self.noteTextLabel.text);
    [self setNeedsDisplay];
}

This fails to set the text field of the UILabel and the output of the log messages is:

2008-11-03 18:09:05.611 VisualNotes[5959:20b] Text Value of Note = Test Note 1  
2008-11-03 18:09:05.619 VisualNotes[5959:20b] Text Value of Note Text Label = (null)

I have also tried to set the text field of UILabel using the following syntax:

[self.noteTextLabel setText:newNote.noteText];

This does not seem to make a difference.

Any help would be much appreciated.

Answer 1

Have you set up your noteTextLabel anywhere? What this looks like to me is that you're messaging a nil object. When you cell is created, noteTextLabel is nil. If you never set it up, you're basically doing the following:

[nil setText: newNote.noteText];

And when you later try to access it, you're doing this:

[nil text];

Which will return nil.

In your -initWithFrame:reuseIdentifier: method, you need to explicitly create your noteTextLabel, and add it as a subview to your cell's content view:

self.noteTextLabel = [[[UILabel alloc] initWithFrame: CGRectMake(0, 0, 200, 20)] autorelease];
[self.contentView addSubview: self.noteTextLabel];

Then this should work.

Also, as a stylistic note, I would make the property for noteTextLabel readonly, since you're only going to want to access it from outside the class, never set it.