mastodon-app-ufficiale-ipho.../MastodonSDK/Sources/MastodonUI/View/Container/MediaGridContainerView.swift

269 lines
10 KiB
Swift

//
// MediaGridContainerView.swift
// MediaGridContainerView
//
// Created by Cirno MainasuK on 2021-8-23.
// Copyright © 2021 Twidere. All rights reserved.
//
import UIKit
import func AVFoundation.AVMakeRect
public protocol MediaGridContainerViewDelegate: AnyObject {
func mediaGridContainerView(_ container: MediaGridContainerView, didTapMediaView mediaView: MediaView, at index: Int)
func mediaGridContainerView(_ container: MediaGridContainerView, mediaSensitiveButtonDidPressed button: UIButton)
}
public final class MediaGridContainerView: UIView {
static let sensitiveToggleButtonSize = CGSize(width: 34, height: 34)
public static let maxCount = 9
public weak var delegate: MediaGridContainerViewDelegate?
public private(set) lazy var viewModel: ViewModel = {
let viewModel = ViewModel()
viewModel.bind(view: self)
return viewModel
}()
// lazy var is required here to setup gesture recognizer target-action
// Swift not doesn't emit compiler error if without `lazy` here
private(set) lazy var _mediaViews: [MediaView] = {
var mediaViews: [MediaView] = []
for i in 0..<MediaGridContainerView.maxCount {
// init media view
let mediaView = MediaView()
mediaView.tag = i
mediaViews.append(mediaView)
// add gesture recognizer
let tapGesture = UITapGestureRecognizer.singleTapGestureRecognizer
tapGesture.addTarget(self, action: #selector(MediaGridContainerView.mediaViewTapGestureRecognizerHandler(_:)))
mediaView.container.addGestureRecognizer(tapGesture)
mediaView.container.isUserInteractionEnabled = true
}
return mediaViews
}()
let contentWarningOverlay = ContentWarningOverlayView()
public override init(frame: CGRect) {
super.init(frame: frame)
_init()
}
public required init?(coder: NSCoder) {
super.init(coder: coder)
_init()
}
public override var accessibilityElements: [Any]? {
get {
mediaViews
}
set { }
}
}
extension MediaGridContainerView {
private func _init() {
contentWarningOverlay.isUserInteractionEnabled = false
contentWarningOverlay.isHidden = true
}
}
extension MediaGridContainerView {
@objc private func mediaViewTapGestureRecognizerHandler(_ sender: UITapGestureRecognizer) {
guard let index = _mediaViews.firstIndex(where: { $0.container === sender.view }) else { return }
let mediaView = _mediaViews[index]
delegate?.mediaGridContainerView(self, didTapMediaView: mediaView, at: index)
}
@objc private func sensitiveToggleButtonDidPressed(_ sender: UIButton) {
delegate?.mediaGridContainerView(self, mediaSensitiveButtonDidPressed: sender)
}
}
extension MediaGridContainerView {
public func dequeueMediaView(adaptiveLayout layout: AdaptiveLayout) -> MediaView {
prepareForReuse()
let mediaView = _mediaViews[0]
layout.layout(in: self, mediaView: mediaView)
layoutContentWarningOverlay()
bringSubviewToFront(contentWarningOverlay)
return mediaView
}
public func dequeueMediaView(gridLayout layout: GridLayout) -> [MediaView] {
prepareForReuse()
let mediaViews = Array(_mediaViews[0..<layout.count])
layout.layout(in: self, mediaViews: mediaViews)
layoutContentWarningOverlay()
bringSubviewToFront(contentWarningOverlay)
return mediaViews
}
public func prepareForReuse() {
_mediaViews.forEach { view in
view.removeFromSuperview()
view.removeConstraints(view.constraints)
view.prepareForReuse()
}
subviews.forEach { view in
view.removeFromSuperview()
}
removeConstraints(constraints)
}
}
extension MediaGridContainerView {
private func layoutContentWarningOverlay() {
contentWarningOverlay.translatesAutoresizingMaskIntoConstraints = false
addSubview(contentWarningOverlay)
contentWarningOverlay.pinToParent()
}
}
extension MediaGridContainerView {
public var mediaViews: [MediaView] {
_mediaViews.filter { $0.superview != nil }
}
public func setAlpha(_ alpha: CGFloat) {
_mediaViews.forEach { $0.alpha = alpha }
}
public func setAlpha(_ alpha: CGFloat, index: Int) {
if index < _mediaViews.count {
_mediaViews[index].alpha = alpha
}
}
}
extension MediaGridContainerView {
public struct AdaptiveLayout {
let aspectRatio: CGSize
let maxSize: CGSize
func layout(in view: UIView, mediaView: MediaView) {
let imageViewSize = AVMakeRect(aspectRatio: aspectRatio, insideRect: CGRect(origin: .zero, size: maxSize)).size
mediaView.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(mediaView)
NSLayoutConstraint.activate([
mediaView.topAnchor.constraint(equalTo: view.topAnchor),
mediaView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
mediaView.trailingAnchor.constraint(equalTo: view.trailingAnchor).priority(.defaultLow),
mediaView.bottomAnchor.constraint(equalTo: view.bottomAnchor),
mediaView.widthAnchor.constraint(equalToConstant: imageViewSize.width).priority(.required - 1),
mediaView.heightAnchor.constraint(equalToConstant: imageViewSize.height).priority(.required - 1),
])
}
}
public struct GridLayout {
static let spacing: CGFloat = 1
let count: Int
let maxSize: CGSize
init(count: Int, maxSize: CGSize) {
self.count = min(count, 9)
self.maxSize = maxSize
}
private func createStackView(axis: NSLayoutConstraint.Axis) -> UIStackView {
let stackView = UIStackView()
stackView.axis = axis
stackView.semanticContentAttribute = .forceLeftToRight
stackView.spacing = GridLayout.spacing
stackView.distribution = .fillEqually
return stackView
}
public func layout(in view: UIView, mediaViews: [MediaView]) {
let containerVerticalStackView = createStackView(axis: .vertical)
containerVerticalStackView.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(containerVerticalStackView)
containerVerticalStackView.pinToParent()
let count = mediaViews.count
switch count {
case 1:
assertionFailure("should use Adaptive Layout")
containerVerticalStackView.addArrangedSubview(mediaViews[0])
case 2:
let horizontalStackView = createStackView(axis: .horizontal)
containerVerticalStackView.addArrangedSubview(horizontalStackView)
horizontalStackView.addArrangedSubview(mediaViews[0])
horizontalStackView.addArrangedSubview(mediaViews[1])
case 3:
let horizontalStackView = createStackView(axis: .horizontal)
containerVerticalStackView.addArrangedSubview(horizontalStackView)
horizontalStackView.addArrangedSubview(mediaViews[0])
let verticalStackView = createStackView(axis: .vertical)
horizontalStackView.addArrangedSubview(verticalStackView)
verticalStackView.addArrangedSubview(mediaViews[1])
verticalStackView.addArrangedSubview(mediaViews[2])
case 4:
let topHorizontalStackView = createStackView(axis: .horizontal)
containerVerticalStackView.addArrangedSubview(topHorizontalStackView)
topHorizontalStackView.addArrangedSubview(mediaViews[0])
topHorizontalStackView.addArrangedSubview(mediaViews[1])
let bottomHorizontalStackView = createStackView(axis: .horizontal)
containerVerticalStackView.addArrangedSubview(bottomHorizontalStackView)
bottomHorizontalStackView.addArrangedSubview(mediaViews[2])
bottomHorizontalStackView.addArrangedSubview(mediaViews[3])
case 5...9:
let topHorizontalStackView = createStackView(axis: .horizontal)
containerVerticalStackView.addArrangedSubview(topHorizontalStackView)
topHorizontalStackView.addArrangedSubview(mediaViews[0])
topHorizontalStackView.addArrangedSubview(mediaViews[1])
topHorizontalStackView.addArrangedSubview(mediaViews[2])
func mediaViewOrPlaceholderView(at index: Int) -> UIView {
return index < mediaViews.count ? mediaViews[index] : UIView()
}
let middleHorizontalStackView = createStackView(axis: .horizontal)
containerVerticalStackView.addArrangedSubview(middleHorizontalStackView)
middleHorizontalStackView.addArrangedSubview(mediaViews[3])
middleHorizontalStackView.addArrangedSubview(mediaViews[4])
middleHorizontalStackView.addArrangedSubview(mediaViewOrPlaceholderView(at: 5))
if count > 6 {
let bottomHorizontalStackView = createStackView(axis: .horizontal)
containerVerticalStackView.addArrangedSubview(bottomHorizontalStackView)
bottomHorizontalStackView.addArrangedSubview(mediaViewOrPlaceholderView(at: 6))
bottomHorizontalStackView.addArrangedSubview(mediaViewOrPlaceholderView(at: 7))
bottomHorizontalStackView.addArrangedSubview(mediaViewOrPlaceholderView(at: 8))
}
default:
assertionFailure()
return
}
let containerWidth = maxSize.width
let containerHeight = count > 6 ? containerWidth : containerWidth * 2 / 3
NSLayoutConstraint.activate([
view.widthAnchor.constraint(equalToConstant: containerWidth).priority(.required - 1),
view.heightAnchor.constraint(equalToConstant: containerHeight).priority(.required - 1),
])
}
}
}