smoothScrollToPosition crash

[SiminaNicolae]

Hi, I tried to smooth scroll to next item from carousel using two buttons(left and right). For this I used the following:

• left navigation: carouselLayoutManager.smoothScrollToPosition(listHorizontalRecyclerView, null, carouselLayoutManager.getCenterItemPosition() - 1);
• right navigation: carouselLayoutManager.smoothScrollToPosition(listHorizontalRecyclerView, null, carouselLayoutManager.getCenterItemPosition() + 1); Right navigation works good, but on left navigation, when I am on first item and try to navigate another one step to left, app crash, for both infinite and non infinite scroll modes.

Process: com.azoft.carousellayoutmanager.sample, PID: 31908 java.lang.IllegalArgumentException: Invalid target position at android.support.v7.widget.RecyclerView$SmoothScroller.start(RecyclerView.java:9562) at android.support.v7.widget.RecyclerView$LayoutManager.startSmoothScroll(RecyclerView.java:6596) at com.azoft.carousellayoutmanager.CarouselLayoutManager.smoothScrollToPosition(CarouselLayoutManager.java:193)

There is a workaround for example for non infinite scroll to check when navigate left if carouselLayoutManager.getCenterItemPosition() != 0, but the issue is still there.

[mig35]

Hi @SiminaNicolae I'll add position check to this code. But generally you should call RecyclerView.smoothScrollToPosition method instead of LayoutManager one. The other thing that both infinite and non-infinite will crash (I'll add this) if you pass wrong position that is not in [0, adapger.getCount()-1]. Are you agree with this? Thanks.

[mig35]

@SiminaNicolae please find this commit https://github.com/Azoft/CarouselLayoutManager/commit/294e16b90375d9f4fe21f6ecf712c33bc276c3b1. If you don't have any objections, I'll create new tag

Thanks

[SiminaNicolae]

Hi @mig35 Thank you for investigating it. I am not 100% sure that with this fix you will still be able to smooth scroll to left if the centered item from carousel is the first one from the list. I am thinking about the case of infinite scroll carousel where you have to go to the end of the list. (but I am sure that you tested it already ;) )

Thanks

[mig35]

@SiminaNicolae This works fine if you pass 0 (this will go to the first element). Bug if you pass carouselLayoutManager.getCenterItemPosition() - 1, then it will crash because this will be -1 and there can not be an element with index -1. And this is true for infinite carousel too. So any way you will have to add code that checks position bounds.

Thanks

[SiminaNicolae]

Ok...thank you.

[mig35]

Hi SiminaNicolae, Upload new version with this checks: 1.1.4

[engzico]

dear mig35

i am also having same issue, not able to do smoothScrollToPositon after initializing the view, RecyclerView.State.getItemCount() giving 0 therefore it is firing "position can't be great then adapter items count. ..."

can you please help

[engzico]

I figured out my problem, it was with my code, it is working fine now, thank you

[azoft-dev-team]

Hi @engzico We also figured out our problem. Fixed in commit cf4fcb2. Upload new version: 1.1.5