iOS Draw a line above label - ios

Question

I have a label in my view. Now I want to draw a line above the label, which means you can see the label is under the line.
So far I can draw a line using quartz2D but always under the label. Is there any way to solve my problems?

Answer 1

You can create a CAShapeLayer like this:
CAShapeLayer *lineLayer = [CAShapeLayer layer];
lineLayer.frame = self.label.bounds;
lineLayer.strokeColor = [UIColor redColor].CGColor;
CGRect rect = CGRectMake(0, CGRectGetMidY(lineLayer.bounds), lineLayer.bounds.size.width, 2);
lineLayer.path = [UIBezierPath bezierPathWithRect:rect].CGPath;
And then add it to the UILabel like this:
[self.label.layer addSublayer:lineLayer];

Answer 2

To be honest, the easiest thing to do is to create a 2x2 pixel image called line#2x.png, and have the bottom 2 pixels black, the top 2 transparent, then use it as the background image for an image view. Stretch the image view to whatever width you need by using it as a pattern image. The 1x image should be a 1x1px, all black.
UIView *lineView = [[UIView alloc] initWithFrame:frame]; // Whatever frame the line needs
// Add the line image as a pattern
UIColor *patternColor = [UIColor colorWithPatternImage:[UIImage imageNamed:#"line.png"]];
lineView.backgroundColor = patternColor;
[self.view addSubview:lineView];

Answer 3

If this is a label you will be using a lot, you could make a sub-class of UILabel and override the drawRect function.
- (void) drawRect:(CGRect)r
{
[super drawRect:r];
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSaveGState(context);
CGContextSetStrokeColorWithColor(context, [UIColor redColor].CGColor);
CGContextSetLineWidth(context, 1.0);
CGContextMoveToPoint(context, 1.0, 1.0);
CGContextAddLineToPoint(context, self.bounds.size.width - 1.0, 1.0);
CGContextStrokePath(context);
CGContextRestoreGState(context);
}
The advantage here is that the line will be "baked" into the view and only be draw once. Other methods such as CAShapeLayer or UIView will be re-rendered every frame.
For bonus points, you can make the color and line width properties :)