How to reduce the amount of time between a tap on a cell and the running of certain code?

Question

I have the below code which successfully causes a cell in a collectionView to depress when tapped.

The issue is that one must hold for pretty long before the depression happens. Don't get me wrong. It's only about 1 second, but if you were to compare that speed to the speed of snapchat you can clearly see snapchat's is almost instant.

func collectionView(_ collectionView: UICollectionView, didHighlightItemAt indexPath: IndexPath) {

     UIView.animate(withDuration: 0.1, animations: {

         collectionView.cellForItem(at: indexPath)!.transform = CGAffineTransform.identity.scaledBy(x: 0.95, y: 0.95)

      })
 }

Question: How could I make this animation for each cell, be instant or closer to it, like snapchat?

Update:

This seems to be doing it:

func collectionView(_ collectionView: UICollectionView, didHighlightItemAt indexPath: IndexPath) {

    UIView.animate(withDuration: 0.1, animations: {

        collectionView.cellForItem(at: indexPath)!.transform = CGAffineTransform.identity.scaledBy(x: 0.95, y: 0.95)

    }) { (true) in

        UIView.animate(withDuration: 0.1, animations: {

            collectionView.cellForItem(at: indexPath)!.transform = CGAffineTransform.identity.scaledBy(x: 1, y: 1)

        })

    }

}

This is an option if anyone wants something basic.

https://developer.apple.com/documentation/uikit/uicollectionviewdelegate/1618032-collectionview?language=objc — canister_exister, Jun 17 '19 at 20:13
@canister_exister, no, that runs after having let go. The method above runs when the user is holding down, because that is when this needs to start. — , Jun 17 '19 at 20:16

score 3 · Accepted Answer · edited Jun 17 '19 at 20:55

3

Disable the collectionView content touch delay in interface builder:

or in code:

myCollectionView.delaysContentTouches = false

Tip: enabling .beginFromCurrentState option for this animation will cause it looks more fluid and responsive. From Apple's docs on beginFromCurrentState:

Start the animation from the current setting associated with an already in-flight animation.

UIView.animate(withDuration: 0.1, delay: 0, options: [.beginFromCurrentState], animations: { 
}) { finished in 
}

edited Jun 17 '19 at 20:55

answered Jun 17 '19 at 20:32

Mojtaba Hosseini

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would this be the correct implementation of your tip?: myCollectionView. beginFromCurrentState = true //because it says there is no .beginFromCurrentState – Jun 17 '19 at 20:38
1

No, its for `UIView.animate` function – Mojtaba Hosseini Jun 17 '19 at 20:43

score 0 · Answer 2 · answered Jun 17 '19 at 20:25

0

If you want instantness you can transform to and back in touchesBegan and touchesEnded/touchesCanceled methods of your custom UICollectionViewCell

answered Jun 17 '19 at 20:25

arturdev

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How to reduce the amount of time between a tap on a cell and the running of certain code?

Update:

2 Answers2