Custom UIPickerView

Hello fellow developers, I am trying to include a UIPickerView that looks like the one shown within Oanda's Currency Coverter, because I think it's nice and neat. Please refer to开发者_JAVA百科 image below.

I have read a few tutorials/samples including Apple's UICatalog but it doesn't seem to show us how to:

1. reduce the number of rows displayed (Oanda showing 3 rows only)
2. change the border colour (Oanda showing a black, and I have seen developers using an UIImage to cover up the edges of UIPickerView)
3. change the highlighted row overlay colour (Oanda has light green)
4. change the size of the picker

Would appreciate any help with sample code.

alt text http://topace.cc/img/photo.jpg

There is some discussion on the resizing of UIPickerView here, some approaches changed between iOS 3 and 4.