Project goal and information

The goal of this project is to recreate the Discover UI in Shazam (which I think is a great, fun way to display content) in combination with a Tinder style of swiping cards to the left/right. The idea behind this is that in some cases, you don't want to swipe away cards, but keep them available for later on. This implementation allows for that. And it's a fun way to interact with content.

It's built with a UICollectionView and a custom flowLayout.

Requirements

• iOS 9.0+
• Swift 5

Installation

CocoaPods

To install with CocoaPods, simply add the following line to your Podfile:

pod 'VerticalCardSwiper'

Carthage

To install with Carthage, simply add the following line to your Podfile:

github "JoniVR/VerticalCardSwiper"

Example

To try out VerticalCardSwiper

pod try VerticalCardSwiper

or open the project and run the Example.

Usage

VerticalCardSwiper behaves a lot like a standard UICollectionView. To use it inside your UIViewController:

import VerticalCardSwiper

class ExampleViewController: UIViewController, VerticalCardSwiperDatasource {
    
    private var cardSwiper: VerticalCardSwiper!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        cardSwiper = VerticalCardSwiper(frame: self.view.bounds)
        view.addSubview(cardSwiper)
        
        cardSwiper.datasource = self
        
        // register cardcell for storyboard use
        cardSwiper.register(nib: UINib(nibName: "ExampleCell", bundle: nil), forCellWithReuseIdentifier: "ExampleCell")
    }
    
    func cardForItemAt(verticalCardSwiperView: VerticalCardSwiperView, cardForItemAt index: Int) -> CardCell {
        
        if let cardCell = verticalCardSwiperView.dequeueReusableCell(withReuseIdentifier: "ExampleCell", for: index) as? ExampleCardCell {
            return cardCell
        }
        return CardCell()
    }
    
    func numberOfCards(verticalCardSwiperView: VerticalCardSwiperView) -> Int {
        return 100
    }
}

Properties

/// Indicates if side swiping on cards is enabled. Set to false if you don't want side swiping. Default is `true`.
@IBInspectable public var isSideSwipingEnabled: Bool = true
/// Allows you to enable/disable the stacking effect. Default is `true` (enabled).
@IBInspectable public var isStackingEnabled: Bool = true
/// The transform animation that is shown on the top card when scrolling through the cards. Default is 0.05.
@IBInspectable public var firstItemTransform: CGFloat = 0.05
/// The inset (spacing) at the top for the cards. Default is 40.
@IBInspectable public var topInset: CGFloat = 40
/// The inset (spacing) at each side of the cards. Default is 20.
@IBInspectable public var sideInset: CGFloat = 20
/// Sets how much of the next card should be visible. Default is 50.
@IBInspectable public var visibleNextCardHeight: CGFloat = 50
/// Vertical spacing between the focussed card and the bottom (next) card. Default is 40.
@IBInspectable public var cardSpacing: CGFloat = 40
/// Allows you to set the view to Stack at the Top or at the Bottom. Default is true.
@IBInspectable public var isStackOnBottom: Bool = true
/// Sets how many cards of the stack are visible in the background
@IBInspectable public var stackedCardsCount: Int = 1
/** 
 Returns an array of indexes (as Int) that are currently visible in the `VerticalCardSwiperView`.
 This includes cards that are stacked (behind the focussed card).
*/
public var indexesForVisibleCards: [Int]

Other

Just like with a regular UICollectionView, you can reload the data by calling

cardSwiper.reloadData()

Get the current focussed card index

cardSwiper.focussedCardIndex

Scroll to a specifc card by calling

cardSwiper.scrollToCard(at: Int, animated: Bool) -> Bool

Get a card at a specified index

cardSwiper.cardForItem(at: Int) -> CardCell?

Swipe a card away programatically

cardSwiper.swipeCardAwayProgrammatically(at: Int, to: SwipeDirection, withDuration: TimeInterval = 0.3) -> Bool

Moving/Deleting/Inserting cards at runtime

Make sure to update your datasource first, otherwise an error will occur.

cardSwiper.moveCard(at: Int, to: Int)
cardSwiper.deleteCards(at: [Int])
cardSwiper.insertCards(at: [Int])

Delegation

To handle swipe gestures, implement the VerticalCardSwiperDelegate.

class ViewController: UIViewController, VerticalCardSwiperDelegate {

    override func viewDidLoad() {
        super.viewDidLoad()

        cardSwiper.delegate = self
    }
    
    func willSwipeCardAway(card: CardCell, index: Int, swipeDirection: SwipeDirection) {
    
        // called right before the card animates off the screen (optional).
    }

    func didSwipeCardAway(card: CardCell, index: Int, swipeDirection: SwipeDirection) {

        // handle swipe gestures (optional).
    }
    
    func didCancelSwipe(card: CardCell, index: Int) {
        
        // Called when a card swipe is cancelled (when the threshold wasn't reached)
    }
    
    func sizeForItem(verticalCardSwiperView: VerticalCardSwiperView, index: Int) -> CGSize {
    
        // Allows you to return custom card sizes (optional).
        return CGSize(width: verticalCardSwiperView.frame.width * 0.75, height: verticalCardSwiperView.frame.height * 0.75)
    }
    
    func didScroll(verticalCardSwiperView: VerticalCardSwiperView) {
    
        // Tells the delegate when the user scrolls through the cards (optional).
    }
    
    func didEndScroll(verticalCardSwiperView: VerticalCardSwiperView) {
    
        // Tells the delegate when scrolling through the cards came to an end (optional).
    }
    
    func didDragCard(card: CardCell, index: Int, swipeDirection: SwipeDirection) {
    
        // Called when the user starts dragging a card to the side (optional).
    }
    
    func didTapCard(verticalCardSwiperView: VerticalCardSwiperView, index: Int) {
    
        // Tells the delegate when the user taps a card (optional).
    }
    
    func didHoldCard(verticalCardSwiperView: VerticalCardSwiperView, index: Int, state: UIGestureRecognizer.State) {
    
        // Tells the delegate when the user holds a card (optional).
    }
}

Customization

Subclass the CardCell to customize the cards.

class ExampleCardCell: CardCell {

}

Key Features

• Shazam Discover UI with paging
• Tinder-style swiping
• Option to disable side swiping
• Set custom number of stacked cards
• Code documentation in README.md file
• Cocoapods support
• Carthage support
• SPM support
• Diff support

Author

Joni Van Roost, [email protected]

License

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

More

Feel free to submit a pull request, open an issue or fork this project. Any help is always appreciated. A big thank you to all the contributors!