I love this feature (well, my son loves it), and I would like to implement it in a kid's book app I am doing for iPhone, but I'm clueless where to begin. I'm using Cocos2d for all the animated sprite/transition stuff, but I'm not sure how to approach highlighting text as it is narrated.
Example: "Jack and Jill, drank their fill, and were too drunk to go for water." As the text is narrated (.mp3 plays on each page), the text would be highlighted. I considered investigating Core animation, but I"m more familiar with Cocs2d at this point (tenuously at best).
If someone has a clue, I'd really appreciate it.
Brendang
解决方案
Use the UIStringDrawing methods to determine the rect needed for the highlight, and then position a semitransparent UIView (or whatever cocos2d uses) under your text view. Synchronize with your audio via NSTimer
