Improve demo app UI (#648)

Demo/Demo/Gravatar-Demo/Common/BaseFormViewController.swift

@@ -0,0 +1,84 @@
+import UIKit
+import Combine
+
+struct FormSection: SectionTitle, Hashable {
+    var sectionTitle: String
+}
+
+class FormField: NSObject, @unchecked Sendable {
+    @MainActor
+    func dequeueCell(in tableView: UITableView, for indexPath: IndexPath) -> UITableViewCell { fatalError() }
+}
+
+class BaseFormViewController: UITableViewController {
+    @Published var fieldText: String = ""
+
+    var cancellables = Set<AnyCancellable>()
+
+    let section = FormSection(sectionTitle: "")
+
+    var snapshot = NSDiffableDataSourceSnapshot<FormSection, FormField>()
+    lazy var dataSource: UITableViewDiffableDataSource = SectionTitleTableViewDiffibleDataSource<FormSection, FormField>(tableView: tableView) {
+        (tableView: UITableView, indexPath: IndexPath, formField: FormField) -> UITableViewCell? in
+        let cell = formField.dequeueCell(in: tableView, for: indexPath)
+        cell.backgroundView?.backgroundColor = .secondarySystemBackground
+        cell.backgroundColor = .secondarySystemBackground
+        cell.contentView.backgroundColor = .secondarySystemBackground
+        cell.accessoryView?.backgroundColor = .secondarySystemBackground
+        return cell
+    }
+
+    var form: [FormField] { [] }
+
+    override func viewDidLoad() {
+        super.viewDidLoad()
+        tableView.allowsSelection = false
+        snapshot.appendSections([section])
+        snapshot.appendItems(form)
+        dataSource.apply(snapshot)
+        view.backgroundColor = .secondarySystemBackground
+        tableView.separatorStyle = .none
+        tableView.rowHeight = UITableView.automaticDimension
+        tableView.delaysContentTouches = false
+    }
+
+    func replace(_ oldFormField: FormField, with newFormField: FormField, after: FormField) {
+        snapshot.deleteItems([oldFormField])
+        if snapshot.indexOfItem(newFormField) == nil {
+            snapshot.insertItems([newFormField], afterItem: after)
+        }
+        dataSource.apply(snapshot)
+    }
+
+    func update(_ field: FormField, animated: Bool = false) {
+        update([field])
+    }
+
+    func update(_ fields: [FormField], animated: Bool = false) {
+        snapshot.reloadItems(fields)
+        dataSource.apply(snapshot, animatingDifferences: animated)
+    }
+
+
+}
+
+class SectionTitleTableViewDiffibleDataSource<SectionType: Hashable, ItemType: Hashable>: UITableViewDiffableDataSource<SectionType, ItemType> where SectionType: SectionTitle, SectionType: Sendable, ItemType: Sendable {
+
+    override func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
+        return sectionIdentifier(for: section)?.sectionTitle
+    }
+}
+
+protocol SectionTitle {
+    var sectionTitle: String { get }
+}
+
+extension UIControl {
+    func removeAllActions() {
+        enumerateEventHandlers { action, _, event, _ in
+            if let action = action {
+                removeAction(action, for: event)
+            }
+        }
+    }
+}

Demo/Demo/Gravatar-Demo/Common/FormFields/ButtonField.swift

@@ -0,0 +1,56 @@
+import UIKit
+
+final class ButtonField: FormField, @unchecked Sendable {
+    var title: String
+    var isActionButton: Bool
+    var isEnabled: Bool
+
+    private let cellID = "ButtonCell"
+    private let action: UIAction
+
+    @MainActor
+    init(title: String, isActionButton: Bool = false, enabled: Bool = true, action actionHandler: @escaping UIActionHandler) {
+        self.title = title
+        self.isActionButton = isActionButton
+        self.isEnabled = enabled
+        self.action = UIAction(handler: actionHandler)
+    }
+
+    @MainActor
+    override func dequeueCell(in tableView: UITableView, for indexPath: IndexPath) -> UITableViewCell {
+        let cell = tableView.dequeueReusableCell(withIdentifier: cellID) as? ButtonCell ?? ButtonCell(reuseIdentifier: cellID)
+        cell.update(with: self)
+        cell.button.removeAllActions()
+        cell.button.addAction(action, for: .touchUpInside)
+        return cell
+    }
+}
+
+private final class ButtonCell: UITableViewCell {
+    let button = UIButton()
+
+    init(reuseIdentifier: String?) {
+        super.init(style: .default, reuseIdentifier: reuseIdentifier)
+        button.translatesAutoresizingMaskIntoConstraints = false
+
+        self.contentView.addSubview(button)
+        NSLayoutConstraint.activate([
+            contentView.centerXAnchor.constraint(equalTo: button.centerXAnchor),
+            contentView.topAnchor.constraint(equalTo: button.topAnchor),
+            contentView.bottomAnchor.constraint(equalTo: button.bottomAnchor, constant: 8),
+        ])
+    }
+
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+
+    func update(with field: ButtonField) {
+        var config = field.isActionButton ? UIButton.Configuration.borderedProminent() : .plain()
+        config.title = field.title
+        button.configuration = config
+        button.isEnabled = field.isEnabled
+        button.sizeToFit()
+    }
+}
+

Demo/Demo/Gravatar-Demo/Common/FormFields/ButtonLabelField.swift

@@ -0,0 +1,56 @@
+import UIKit
+
+final class ButtonLabelField: FormField, @unchecked Sendable {
+    var buttonTitle: String
+    var title: String
+    var subtitle: String?
+    var isEnabled: Bool
+
+    private let cellID = "ButtonCellCell"
+    private let action: UIAction
+
+    @MainActor
+    init(title: String, subtitle: String?, buttonTitle: String, isEnabled: Bool = true, action actionHandler: @escaping UIActionHandler) {
+        self.title = title
+        self.subtitle = subtitle
+        self.buttonTitle = buttonTitle
+        self.isEnabled = isEnabled
+        self.action = UIAction(handler: actionHandler)
+    }
+
+    @MainActor
+    override func dequeueCell(in tableView: UITableView, for indexPath: IndexPath) -> UITableViewCell {
+        let cell = tableView.dequeueReusableCell(withIdentifier: cellID) as? ButtonLabelCell ?? ButtonLabelCell(reuseIdentifier: cellID)
+        cell.update(with: self)
+        cell.button.removeAllActions()
+        cell.button.addAction(action, for: .touchUpInside)
+        return cell
+    }
+}
+
+private final class ButtonLabelCell: UITableViewCell {
+    let button = UIButton()
+
+    init(reuseIdentifier: String?) {
+        super.init(style: .default, reuseIdentifier: reuseIdentifier)
+        accessoryView = button
+    }
+
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+
+    func update(with field: ButtonLabelField) {
+        var config = UIButton.Configuration.plain()
+        config.title = field.buttonTitle
+        button.configuration = config
+        button.sizeToFit()
+        button.isEnabled = field.isEnabled
+
+        var cellConfig = self.defaultContentConfiguration()
+        cellConfig.text = field.title
+        cellConfig.secondaryText = field.subtitle
+
+        self.contentConfiguration = cellConfig
+    }
+}

Demo/Demo/Gravatar-Demo/Common/FormFields/ImageFormField.swift

@@ -0,0 +1,62 @@
+import UIKit
+import Combine
+
+class ImageFormField: FormField, @unchecked Sendable, UITextFieldDelegate {
+    var image: UIImage?
+    var size: CGSize
+    private(set) var imageView: UIImageView?
+    private var cancellables = Set<AnyCancellable>()
+
+    private let cellID = "ImageFormCell"
+
+    init(image: UIImage? = nil, size: CGSize) {
+        self.image = image
+        self.size = size
+    }
+
+    @MainActor
+    override func dequeueCell(in tableView: UITableView, for indexPath: IndexPath) -> UITableViewCell {
+        let cell = tableView.dequeueReusableCell(withIdentifier: cellID) as? ImageCell ?? ImageCell(reuseIdentifier: cellID)
+        cell.update(with: self)
+        imageView = cell.formImageView
+        cell.formImageView.publisher(for: \.image).sink { [weak self] image in
+            self?.image = image
+        }.store(in: &cancellables)
+
+        return cell
+    }
+}
+
+private final class ImageCell: UITableViewCell {
+    let formImageView = UIImageView()
+
+    private lazy var widthConstraint: NSLayoutConstraint = formImageView.widthAnchor.constraint(equalToConstant: 300)
+    private lazy var heightConstraint: NSLayoutConstraint = formImageView.heightAnchor.constraint(equalToConstant: 300)
+
+    init(reuseIdentifier: String?) {
+        super.init(style: .default, reuseIdentifier: reuseIdentifier)
+        formImageView.translatesAutoresizingMaskIntoConstraints = false
+        formImageView.backgroundColor = .tertiarySystemBackground
+
+        self.contentView.addSubview(formImageView)
+        NSLayoutConstraint.activate([
+            contentView.centerXAnchor.constraint(equalTo: formImageView.centerXAnchor),
+            contentView.topAnchor.constraint(equalTo: formImageView.topAnchor),
+            contentView.bottomAnchor.constraint(equalTo: formImageView.bottomAnchor, constant: 8),
+            widthConstraint,
+            heightConstraint
+        ])
+    }
+
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+
+    func update(with config: ImageFormField) {
+        widthConstraint.constant = config.size.width
+        heightConstraint.constant = config.size.height
+        if let image = config.image {
+            formImageView.image = image
+        }
+    }
+}

Demo/Demo/Gravatar-Demo/Common/FormFields/LabelField.swift

@@ -0,0 +1,24 @@
+import UIKit
+
+final class LabelField: FormField, @unchecked Sendable {
+    var title: String?
+    var subtitle: String?
+    private let cellID = "LabelCell"
+
+    init(title: String? = nil, subtitle: String? = nil) {
+        self.title = title
+        self.subtitle = subtitle
+    }
+
+    @MainActor
+    override func dequeueCell(in tableView: UITableView, for indexPath: IndexPath) -> UITableViewCell {
+        let cell = tableView.dequeueReusableCell(withIdentifier: cellID) ?? UITableViewCell(style: .subtitle, reuseIdentifier: cellID)
+
+        var config = cell.defaultContentConfiguration()
+        config.text = title
+        config.secondaryText = subtitle
+        cell.contentConfiguration = config
+
+        return cell
+    }
+}

Demo/Demo/Gravatar-Demo/Common/FormFields/SegmentedControlField.swift

@@ -0,0 +1,63 @@
+import UIKit
+
+class SegmentedControlField: FormField, @unchecked Sendable, UITextFieldDelegate {
+    typealias OnSegmentSelected = (String, Int) -> Void
+
+    var segments: [String]
+    let actionHandler: OnSegmentSelected?
+
+    @Published var selectedIndex: Int
+    @Published var selectedSegment: String = ""
+
+    private let cellID = "ImageFormCell"
+
+    init(segments: [String], selectedIndex: Int = 0, action actionhandler: OnSegmentSelected? = nil) {
+        self.segments = segments
+        self.selectedIndex = selectedIndex
+        self.actionHandler = actionhandler
+        if segments.indices.contains(selectedIndex) {
+            selectedSegment = segments[selectedIndex]
+        }
+    }
+
+    @MainActor
+    override func dequeueCell(in tableView: UITableView, for indexPath: IndexPath) -> UITableViewCell {
+        let cell = tableView.dequeueReusableCell(withIdentifier: cellID) as? SegmentedControlCell ?? SegmentedControlCell(reuseIdentifier: cellID)
+        cell.update(with: self)
+        cell.selector.addAction(UIAction { [weak self] _ in
+            guard let self else { return }
+            selectedIndex = cell.selector.selectedSegmentIndex
+            selectedSegment = segments[selectedIndex]
+            actionHandler?(selectedSegment, selectedIndex)
+        }, for: .valueChanged)
+        return cell
+    }
+}
+
+private final class SegmentedControlCell: UITableViewCell {
+    let selector = UISegmentedControl()
+
+    init(reuseIdentifier: String?) {
+        super.init(style: .default, reuseIdentifier: reuseIdentifier)
+        selector.translatesAutoresizingMaskIntoConstraints = false
+
+        self.contentView.addSubview(selector)
+        NSLayoutConstraint.activate([
+            contentView.centerXAnchor.constraint(equalTo: selector.centerXAnchor),
+            contentView.topAnchor.constraint(equalTo: selector.topAnchor),
+            contentView.bottomAnchor.constraint(equalTo: selector.bottomAnchor, constant: 8),
+        ])
+    }
+
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+
+    func update(with config: SegmentedControlField) {
+        selector.removeAllSegments()
+        config.segments.enumerated().forEach {
+            selector.insertSegment(withTitle: $1, at: $0, animated: true)
+        }
+        selector.selectedSegmentIndex = config.selectedIndex
+    }
+}