Slippery

Example

To run the example project, clone the repo, and run pod install from the Example directory first.

Requirements

Swift 5.1 iOS 11.0 - 13.0

Installation

CocoaPods

Slippery is available through CocoaPods. To install it, simply add the following line to your Podfile:

pod 'Slippery'

Swift Package Manager

xcode -> Projects -> Swift Package Manager

https://github.com/ShawnBaek/Slippery.git

Storyboard

Drag UICollectionViewController or UICollectionView in UIViewController

Set CollectionViewFlowLayout as SlipperyFlowLayout

That's It

Center Mode

Center Mode has two options.

1. cropping

cropping mode is cropping the first and last cell

highlightOption: .center(.cropping)

2. normal

first and the last cell is always positioning at center.

highlightOption: .center(.normal)

Custom Mode

You can set specifit focused position from leading to first, second, third, fourth and fifth

highlightOption: .custom(.leading, .third)

Check Example of SliceVC

Scale and Opacity Options

You can fully customizing focusing options.

self.collectionViewLayout.minimumOpacityFactor = 0.1
self.collectionViewLayout.minimumScaleFactor = 1.0

e.g. minimumScaleFactor = 1.0 means disable the scale mode e.g. minimumScaleFactor = 0.4 means set other cells scale as 0.4

Sample Project

func setupCollectionView(){

    self.collectionViewLayout = SlipperyFlowLayout.configureLayout(collectionView: self.calendarView, itemSize: CGSize(width: 120, height: 180), minimumLineSpacing: 10, highlightOption: .center(.cropping))
    self.collectionViewLayout.scaleItems = true
    self.collectionViewLayout.invalidateLayout()
    self.calendarView.layoutIfNeeded()

}

func setupCollectionView(){

    self.collectionViewLayout = SlipperyFlowLayout.configureLayout(collectionView: self.sliceView, itemSize: CGSize(width: 30, height: 180), minimumLineSpacing: 20, highlightOption: .custom(.leading, .third))

    self.collectionViewLayout.invalidateLayout()
    self.sliceView.layoutIfNeeded()

}

func setupCollectionView(){

    self.collectionViewLayout = SlipperyFlowLayout.configureLayout(collectionView: self.photoView, itemSize: CGSize(width: 150, height: 180), minimumLineSpacing: 20, highlightOption: .center(.normal))

    self.collectionViewLayout.invalidateLayout()
    self.photoView.layoutIfNeeded()

}

scrollToItem

create a scrollToItem function in your ViewController

override func viewDidLoad() {
    super.viewDidLoad()
    createDummyNumbers()

    setupCollectionView()
    scrollToItem(item: 20, animated: true)
}

func createDummyNumbers(){

    for i in 0 ... 100 {
    dummyNumbers.append(i)
    }
}

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    self.view.layoutIfNeeded()
}

func scrollToItem(item: Int, animated: Bool) {

    let itemOffset = self.collectionViewLayout.updateOffset(item: item)
    self.calendarView.setContentOffset(CGPoint(x: itemOffset, y: 0), animated: true)
    self.calendarView.layoutIfNeeded()

}

Acknowledgment

I make this Library inspired by LGLinearFlow. Thank you for sharing your code.

Author

shawnbaek, shawn@shawnbaek.com

Contact

I want to connect developers who loves iOS development. Follow me and Let's keep in touch. I want to make a friends! :smaile: twitter

License

Slippery is available under the MIT license. See the LICENSE file for more info.