UILabel添加下划线

重写UILabel:

- (void)drawRect:(CGRect)rect{    [super drawRect:rect];    CGContextRef ctx = UIGraphicsGetCurrentContext();    CGSize fontSize =[self.text sizeWithFont:self.font                                    forWidth:self.bounds.size.width                               lineBreakMode:UILineBreakModeTailTruncation];            // Get the fonts color.        const float * colors = CGColorGetComponents(self.textColor.CGColor);    // Sets the color to draw the line    CGContextSetRGBStrokeColor(ctx, colors[0], colors[1], colors[2], 1.0f); // Format : RGBA    // Line Width : make thinner or bigger if you want    CGContextSetLineWidth(ctx, 1.0f);        // Calculate the starting point (left) and target (right)    CGPoint l = CGPointMake(0,                            self.frame.size.height/2.0 +fontSize.height/2.0);        CGPoint r = CGPointMake(fontSize.width,                            self.frame.size.height/2.0 + fontSize.height/2.0);            // Add Move Command to point the draw cursor to the starting point    CGContextMoveToPoint(ctx, l.x, l.y);        // Add Command to draw a Line    CGContextAddLineToPoint(ctx, r.x, r.y);            // Actually draw the line.    CGContextStrokePath(ctx);        // should be nothing, but who knows...    [super drawRect:rect];   }