UIButton with visible highlight changes

gistfile1.m

- (void)drawRect:(CGRect)rect
{
    CGRect bounds = [self bounds];
    UIColor *color = [self isHighlighted] ? [UIColor blueColor] : [UIColor whiteColor];
    [color setFill];
    [[UIBezierPath bezierPathWithRect:bounds] fill];
}

- (void)setHighlighted:(BOOL)highlighted;
{
    [super setHighlighted:highlighted];
    [self setNeedsDisplay];
}