Added a FittableLabelRoot class

Source/FittableLabelRoot.swift

@@ -0,0 +1,69 @@
+//
+//  FittableLabelRoot.swift
+//  
+//
+//  Created by Tyson_Freeze on 12/31/21.
+//
+
+import UIKit
+
+/// A UIView subclass to give the FittableFontLabel package a root to recursively search for UILabels within.
+open class FittableLabelRoot: UIView {
+
+    /// If true, this view and it's subviews will be searched for any UILabels with a fontSizeLinkIdentifier.
+    @IBInspectable public var searchView: Bool = true
+
+    // MARK: Private
+
+    private var fontSizeLinks: [String : fontSizeLink] = [:]
+
+    private class fontSizeLink {
+        var minimumFontSize: CGFloat = CGFloat.greatestFiniteMagnitude
+        var labels: [FittableFontLabel] = []
+
+        init(label: FittableFontLabel) {
+            add(label: label)
+        }
+
+        func add(label: FittableFontLabel) {
+            labels.append(label)
+            if label.autoAdjustFontSize {
+                minimumFontSize = min(minimumFontSize, label.font.pointSize)
+            }
+        }
+    }
+
+    // MARK: Life cycle
+
+    open override func draw(_ rect: CGRect) {
+        updateFontSizeLinks(in: self)
+        standardizeFontSizes()
+    }
+
+    // MARK: Search
+
+    private func updateFontSizeLinks(in view: UIView) {
+        for subview in view.subviews {
+            print(subview.self)
+            if let label = subview as? FittableFontLabel {
+                if let fontSizeLinkIdentifier = label.fontSizeLinkIdentifier {
+                    if let fontSizeLink = fontSizeLinks[fontSizeLinkIdentifier] {
+                        fontSizeLink.add(label: label)
+                    } else {
+                        fontSizeLinks[fontSizeLinkIdentifier] = fontSizeLink(label: label)
+                    }
+                }
+            } else {
+                updateFontSizeLinks(in: subview)
+            }
+        }
+    }
+
+    private func standardizeFontSizes() {
+        for fontLink in fontSizeLinks.values {
+            for label in fontLink.labels {
+                label.font = label.font.withSize(fontLink.minimumFontSize)
+            }
+        }
+    }
+}