问题
I was printing the list of points I get using this two methods of touch tracking.
The gesture recognisers are easier to use, but if you compare the points you get with the touchesBegan procedure, recognisers avoid some points, specifically at the beginning of the motions.
Does anybody know if there is a difference regarding accuracy between this two procedures?
Thanks!
回答1:
I believe gesture recognizers would need some time initially to assert that it has detected the correct gesture. For example, if we do a swipe gesture, ios would first wait to confirm that it was not a tap gesture.
Hence, gesture recognizers may not be printing the points at the beginning of the motion.
As mentioned on developer documentation here:
Gesture recognizers may delay the delivery of touch objects to the view while they are recognizing gestures, and by default they cancel delivery of remaining touch objects to the view once they recognize their gesture.
A helpful detailed example can be found at this link.
Hope this helps.
来源：https://stackoverflow.com/questions/11851464/uigesturerecognizers-vs-touchesbegan-touchesmoved-touchesended-accuracy