How to allow UICollectionView to scroll in intervals of the cell width - ios

I have a UICollectionView that scrolls sideways. When it is scrolled I want it to land on a multiple of the cell width. The cells are diamonds and must fit in a very precise location.
Example: If user scrolls, then the scroll will happen as normal (or maybe semi-paged) and then when it stops, make sure it stops at a multiple so the cell can be aligned with the diamonds.
Any idea how to approach this?

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UICollectionView specific cell bring front of oder cell

As you can see in below video, in collectionView there are 3 cells. I want it become bigger when I touch in centre. everything is OK except one thing.
As you can see in video when order cell is visible and centre cell is bigger in bring to back of visible cell and make it untouchable.
https://www.dropbox.com/s/cn4ujvr6t9f9e2c/ScreenRecording_07-14-2018%2013-08-04.MP4?dl=0
Is there any solution that centre cell always be in front of order cell?

Determine when UICollectionViewCell is % off screen as I scroll horizontally

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Snap to cell in a UICollectionView

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Is it possible to figure out what part of the cell is visible from inside the cell subclass?

In my cell subclass the user can slide the cell for actions, just like in Mail.app. However, the cells can be much larger than Mail.app, sometimes up to 1,000pt which means it requires the table to be scrolled to read fully.
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I have a slightly complicated system that I am having some reuse issues with, wanted to get some feedback. Basically it is a vertical tableview, and each cell contains another tableview that is rotated 90 degrees, so that each cell scrolls horizontally. Each horizontal cell is also set up to scroll infinitely with paginated responses from an API. I am having issues where cells are copying on top of each other when the vertical table is scrolled down. I have reuse identifiers set up correctly and in each of the horizontal tableviews I am running the following:
- (void)prepareForReuse
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This is not a direct way to solve your issue, but I believe if you use a horizontal scroll view inside each vertical cell, you will have this done faster and with less weird behaviours. I also believe this is not a standard way, so weird stuff will happen.
All you do is set or extend the content size of the scroll off screen continuously to create an infinite scrolling behaviour. Create views within the scroll view pragmatically to simulate each cell. Hope this helps.

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