Twitter Bootstrap has a form control that would "glow" on the borders when in active mode, I wonder if that effect could be achieved on iPhone with UITextField. Has anyone tried that?
(http://twitter.github.com/bootstrap/base-css.html search Form Control)
Probably the easiest way to accomplish this is to modify its backing layer:
CALayer *theLayer = [theTextField layer]; [theLayer setBorderWidth:2.]; [theLayer setBorderColor:[[UIColor blueColor] CGColor]]; [theLayer setShadowColor:[[UIColor blueColor] CGColor]]; [theLayer setShadowOpacity:1.]; [theLayer setShadowRadius:5.]; [theLayer setShadowOffset:CGSizeZero]; [theTextField setClipsToBounds:NO];
The biggest disadvantage to this approach, IMO, is that CALayer shadow operations are notoriously slow, so this would be essentially unusable if you are animating (such as in a scroll/table view). There are various enhancements, though, that you can make for higher performance shadows.
(Also, you will obviously not want the ugly dark blue color that I used!)