Signal-iOS/SignalMessaging/ViewControllers/Stickers/StickerHorizontalListView.swift
2019-05-03 09:24:12 -04:00

132 lines
3.7 KiB
Swift

//
// Copyright (c) 2019 Open Whisper Systems. All rights reserved.
//
import Foundation
@objc
public class StickerHorizontalListViewItem: NSObject {
let stickerInfo: StickerInfo
let selectedBlock: () -> Void
@objc
public init(stickerInfo: StickerInfo, selectedBlock: @escaping () -> Void) {
self.stickerInfo = stickerInfo
self.selectedBlock = selectedBlock
}
}
// MARK: -
@objc
public class StickerHorizontalListView: UICollectionView {
private let cellSize: CGFloat
public typealias Item = StickerHorizontalListViewItem
@objc
public var items = [Item]() {
didSet {
AssertIsOnMainThread()
collectionViewLayout.invalidateLayout()
reloadData()
}
}
private let cellReuseIdentifier = "cellReuseIdentifier"
@objc
public override var contentInset: UIEdgeInsets {
didSet {
updateHeightConstraint()
}
}
private var heightConstraint: NSLayoutConstraint?
@objc
public required init(cellSize: CGFloat, spacing: CGFloat = 0) {
self.cellSize = cellSize
let layout = LinearHorizontalLayout(itemSize: CGSize(width: cellSize, height: cellSize), spacing: spacing)
super.init(frame: .zero, collectionViewLayout: layout)
delegate = self
dataSource = self
register(UICollectionViewCell.self, forCellWithReuseIdentifier: cellReuseIdentifier)
setContentHuggingHorizontalLow()
setCompressionResistanceHorizontalLow()
heightConstraint = autoSetDimension(.height, toSize: 0)
updateHeightConstraint()
}
private func updateHeightConstraint() {
guard let heightConstraint = heightConstraint else {
owsFailDebug("Missing heightConstraint.")
return
}
let newValue = cellSize + contentInset.top + contentInset.bottom
if heightConstraint.constant == newValue {
return
}
heightConstraint.constant = newValue
invalidateIntrinsicContentSize()
}
required public init(coder: NSCoder) {
notImplemented()
}
}
// MARK: - UICollectionViewDelegate
extension StickerHorizontalListView: UICollectionViewDelegate {
public func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
Logger.debug("")
guard let item = items[safe: indexPath.row] else {
owsFailDebug("Invalid index path: \(indexPath)")
return
}
item.selectedBlock()
}
}
// MARK: - UICollectionViewDataSource
extension StickerHorizontalListView: UICollectionViewDataSource {
public func numberOfSections(in collectionView: UICollectionView) -> Int {
return 1
}
public func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection sectionIdx: Int) -> Int {
return items.count
}
public func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
// We could eventually use cells that lazy-load the sticker views
// when the cells becomes visible and eagerly unload them.
// But we probably won't need to do that.
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellReuseIdentifier, for: indexPath)
for subview in cell.contentView.subviews {
subview.removeFromSuperview()
}
guard let item = items[safe: indexPath.row] else {
owsFailDebug("Invalid index path: \(indexPath)")
return cell
}
let stickerView = StickerView(stickerInfo: item.stickerInfo)
cell.contentView.addSubview(stickerView)
stickerView.autoPinEdgesToSuperviewEdges()
return cell
}
}