rounded corner uilabel not visible (xcode 4.5.2) - ios

Question

I am new to IOS development, try to create top rounded corner label
by following link
How do I round only the top two corners of a UILabel?
But after applying the mask, the whole label cannot be seen, Any clue?
Here is my code.
#synthesize title;
- (void)viewDidLoad
{
[super viewDidLoad];
title.layer.borderColor=[[UIColor blueColor]CGColor];
title.layer.borderWidth=2;
UIBezierPath *maskPath;
maskPath = [UIBezierPath bezierPathWithRoundedRect:title.bounds byRoundingCorners:(UIRectCornerTopLeft | UIRectCornerTopRight) cornerRadii:CGSizeMake(10.0f, 10.0f)];
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.frame=title.bounds;
maskLayer.path = maskPath.CGPath;
title.layer.mask = maskLayer;
}
EDITED
Tried the suggestion to create the label in program, the layout become
https://docs.google.com/file/d/0B60xg2ZCEjOqeTBEWG92N0NodFU/edit?usp=sharing
The corner disappear and I still want to set the mask the "title" labal?
EDITED
Finally give up, for others benefit,I wrap the label in uiview , map the uiview to a class (i.e. Myview.m), and put the same code in method "- (void)drawRect:(CGRect)rect{}" in "Myview.m". The display showed as what I want!.

Answer 1

I'm not sure if this is your problem because you didn't show how the title label is created, but if you're creating it in code, you need to be sure to alloc/init the label, as well as give it a frame and then add it as a subview of its superview.
title = [[UILabel alloc] initWithFrame:CGRectMake(100.0f, 100.0f, 60.0f, 30.0f)];
title.layer.borderColor=[[UIColor blueColor]CGColor];
title.layer.borderWidth=2;
UIBezierPath *maskPath;
maskPath = [UIBezierPath bezierPathWithRoundedRect:title.bounds byRoundingCorners:(UIRectCornerTopLeft | UIRectCornerTopRight) cornerRadii:CGSizeMake(10.0f, 10.0f)];
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.frame=title.bounds;
maskLayer.path = maskPath.CGPath;
title.layer.mask = maskLayer;
[self.view addSubview:title];

Answer 2

first of all my advice is don't use "title" as a UILabel name because all UIViewController has a property that name is title.
After changing label name and sure IBOutlet is connected add this code:
lblTitle.layer.masksToBounds = YES;
I just figure out if you create a label on storyboard you dont need to alloc again. I wrote this code and it works;
_L_corner.layer.borderColor =[[UIColor blueColor] CGColor];
_L_corner.layer.borderWidth = 5.0f;
_L_corner.layer.cornerRadius = 3.0f;

Answer 3

Finally give up, for others benefit, and used another work around:-
1) wrap the label in uiview ,
2) map the uiview to a class (i.e. Myview.m),
3) put the same code in method
- (void)drawRect:(CGRect)rect{
title.layer.borderColor=[[UIColor blueColor]CGColor];
title.layer.borderWidth=2;
UIBezierPath *maskPath;
maskPath = [UIBezierPath bezierPathWithRoundedRect:title.bounds byRoundingCorners:(UIRectCornerTopLeft | UIRectCornerTopRight) cornerRadii:CGSizeMake(10.0f, 10.0f)];
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.frame=title.bounds;
maskLayer.path = maskPath.CGPath;
title.layer.mask = maskLayer;
}
in "Myview.m".
The display showed as what I want!