Tutorial Sheet (incl. Welcome message + Recordings introduction)

main/Extensions/AutoLayout.swift

@@ -0,0 +1,82 @@
+import UIKit
+
+/*
+  Readable Auto Layout Constraints
+
+  Usage:
+    A.anchor =&= multiplier * B.anchor + constant | priority
+*/
+
+infix operator =&= : AdditionPrecedence
+infix operator =<= : AdditionPrecedence
+infix operator =>= : AdditionPrecedence
+//infix operator | : AdditionPrecedence
+
+/// Create and activate an `equal` constraint between left and right anchor. Format: `A.anchor =&= multiplier * B.anchor + constant | priority`
+@discardableResult func =&= <T>(l: NSLayoutAnchor<T>, r: NSLayoutAnchor<T>) -> NSLayoutConstraint { l.constraint(equalTo: r).on() }
+/// Create and activate a `lessThan` constraint between left and right anchor. Format: `A.anchor =<= multiplier * B.anchor + constant | priority`
+@discardableResult func =<= <T>(l: NSLayoutAnchor<T>, r: NSLayoutAnchor<T>) -> NSLayoutConstraint { l.constraint(lessThanOrEqualTo: r).on() }
+/// Create and activate a `greaterThan` constraint between left and right anchor. Format: `A.anchor =>= multiplier * B.anchor + constant | priority`
+@discardableResult func =>= <T>(l: NSLayoutAnchor<T>, r: NSLayoutAnchor<T>) -> NSLayoutConstraint { l.constraint(greaterThanOrEqualTo: r).on() }
+
+extension NSLayoutDimension { // higher precedence, so multiply first
+	/// Create intermediate anchor multiplier result.
+	static func *(l: CGFloat, r: NSLayoutDimension) -> AnchorMultiplier { .init(anchor: r, m: l) }
+}
+
+/// Intermediate `NSLayoutConstraint` anchor with multiplier supplement
+struct AnchorMultiplier {
+	let anchor: NSLayoutDimension, m: CGFloat
+	
+	/// Create and activate an `equal` constraint between left and right anchor. Format: `A.anchor =&= multiplier * B.anchor + constant | priority`
+	@discardableResult static func =&=(l: NSLayoutDimension, r: Self) -> NSLayoutConstraint { l.constraint(equalTo: r.anchor, multiplier: r.m).on() }
+	/// Create and activate a `lessThan` constraint between left and right anchor. Format: `A.anchor =<= multiplier * B.anchor + constant | priority`
+	@discardableResult static func =<=(l: NSLayoutDimension, r: Self) -> NSLayoutConstraint { l.constraint(lessThanOrEqualTo: r.anchor, multiplier: r.m).on() }
+	/// Create and activate a `greaterThan` constraint between left and right anchor. Format: `A.anchor =>= multiplier * B.anchor + constant | priority`
+	@discardableResult static func =>=(l: NSLayoutDimension, r: Self) -> NSLayoutConstraint { l.constraint(greaterThanOrEqualTo: r.anchor, multiplier: r.m).on() }
+}
+
+extension NSLayoutConstraint {
+	/// Change `isActive`to `true` and return `self`
+	func on() -> Self { isActive = true; return self }
+	/// Change `constant`attribute  and return `self`
+	@discardableResult static func +(l: NSLayoutConstraint, r: CGFloat) -> NSLayoutConstraint { l.constant = r; return l }
+	/// Change `constant` attribute and return `self`
+	@discardableResult static func -(l: NSLayoutConstraint, r: CGFloat) -> NSLayoutConstraint { l.constant = -r; return l }
+	/// Change `priority` attribute and return `self`
+	@discardableResult static func |(l: NSLayoutConstraint, r: UILayoutPriority) -> NSLayoutConstraint { l.priority = r; return l }
+}
+
+/*
+  UIView extension to generate multiple constraints at once
+
+  Usage:
+    child.anchor([.width, .height], to: parent) | .defaultLow
+*/
+
+extension UIView {
+	/// Edges that need the relation to flip arguments. For these we need to inverse the constant value and relation.
+	private static let inverseItem: [NSLayoutConstraint.Attribute] = [.right, .bottom, .trailing, .lastBaseline, .rightMargin, .bottomMargin, .trailingMargin]
+	
+	/// Create and active constraints for provided edges. Constraints will anchor the same edge on both `self` and `other`.
+	/// - Parameters:
+	///   - edges: List of constraint attributes, e.g. `[.top, .bottom, .left, .right]`
+	///   - other: Instance to bind to, e.g. `UIView` or `UILayoutGuide`
+	///   - margin: Used as constant value. Multiplier will always be `1.0`. If you need to change the multiplier, use single constraints instead. (Default: `0`)
+	///   - rel: Constraint relation. (Default: `.equal`)
+	/// - Returns: List of created and active constraints
+	@discardableResult func anchor(_ edges: [NSLayoutConstraint.Attribute], to other: Any, margin: CGFloat = 0, if rel: NSLayoutConstraint.Relation = .equal) -> [NSLayoutConstraint] {
+		edges.map {
+			let (A, B) = UIView.inverseItem.contains($0) ? (other, self) : (self, other)
+			return NSLayoutConstraint(item: A, attribute: $0, relatedBy: rel, toItem: B, attribute: $0, multiplier: 1, constant: margin).on()
+		}
+	}
+}
+
+extension Array where Element: NSLayoutConstraint {
+	/// set `priority` on all elements and return same list
+	@discardableResult static func |(l: Self, r: UILayoutPriority) -> Self {
+		for x in l { x.priority = r }
+		return l
+	}
+}

main/Extensions/Generic.swift

@@ -1,4 +1,4 @@
-import Foundation
+import UIKit
 
 struct QLog {
 	private init() {}
@@ -99,5 +99,15 @@ struct TimeFormat {
 	static func since(_ date: Date, millis: Bool = false) -> String {
 		from(Date().timeIntervalSince(date), millis: millis)
 	}
-	
+}
+
+extension UIColor {
+	static var sysBg: UIColor { get { if #available(iOS 13.0, *) { return .systemBackground } else { return .white } }}
+	static var sysFg: UIColor { get { if #available(iOS 13.0, *) { return .label } else { return .black } }}
+}
+
+extension UIEdgeInsets {
+	init(all: CGFloat = 0, top: CGFloat? = nil, left: CGFloat? = nil, bottom: CGFloat? = nil, right: CGFloat? = nil) {
+		self.init(top: top ?? all, left: left ?? all, bottom: bottom ?? all, right: right ?? all)
+	}
 }

main/Extensions/URL.swift

@@ -10,14 +10,10 @@ fileprivate extension FileManager {
 	func internalDB() -> URL {
 		appGroupDir().appendingPathComponent("dns-logs.sqlite")
 	}
-	func appGroupIPC() -> URL {
-		appGroupDir().appendingPathComponent("data-exchange.dat")
-	}
 }
 
 extension URL {
 	static func exportDir() -> URL { FileManager.default.exportDir() }
 	static func appGroupDir() -> URL { FileManager.default.appGroupDir() }
 	static func internalDB() -> URL { FileManager.default.internalDB() }
-	static func appGroupIPC() -> URL { FileManager.default.appGroupIPC() }
 }