Interesting task: let say that we've got a counter which counts from 0 to 100. Counting up should start when UIButton was pressed. While UIButton is being pressed/highlighted counting up continue.
Conditions:
- counter should count up from 0 to 50 in 2 sec
- counter should count up from 51 to 80 in next 3 sec (from 2 to 5)
- counter should count up from 81 to 100 in next 5 sec (from 5 to 10)
If I release UIButton counter should start counting down from the last value to 0 (decrement by 1 in 1 sec).
If I press UIButton again counter should start counting up.