How to start from the beginning when you reached end of index of array range in swift? -



How to start from the beginning when you reached end of index of array range in swift? -

hey guys i'm beginner of learning swift. in programme have array has 49 items , want print out labels every item 1 1 on screen swiping action (left right , right left). when reach end of array fatal error because of out array index range.

i tried utilize counter variable in order count swipes , set index number 0 when reaches 49 not work. how can cope this? thanks.

if swipecounter == 49{ swipecounter = 0 } firstcell.text = string(numberlist[swipecounter]) secondcell.text = string(numberlist[swipecounter + 1]) thirdcell.text = string(numberlist[swipecounter + 2]) swipecounter = ++swipecounter println(swipecounter)

the error occurring because checking value of swipecounter , increasing it. if swipecounter 48, not set 0 , effort access swipecounter + 2 i.e. 50 result in crash. plus not big fan of using hardcoded lengths in code.

i suggest doing this

firstcell.text = string(numberlist[swipecounter % numberlist.count]) secondcell.text = string(numberlist[(swipecounter + 1) % numberlist.count]) thirdcell.text = string(numberlist[(swipecounter + 2) % numberlist.count])

the modulus operator should handle index overflows , replacing 49 numberlist.count move if array length changes.

hope helps!

arrays swift

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