niw · May 12, 2025 23:02 · May 12, 2025 · May 5, 2025
diff --git a/MainView.swift b/MainView.swift
@@ -0,0 +1,85 @@
+import AppKit
+import SwiftUI
+
+public struct TextView: NSViewRepresentable {
+    @Binding
+    var text: String
+    var font: NSFont?
+
+    public init(
+        text: Binding<String>
+    ) {
+        self._text = text
+    }
+
+    public class Coordinator: NSObject, NSTextViewDelegate {
+        var parent: TextView
+
+        init(_ parent: TextView) {
+            self.parent = parent
+        }
+
+        public func textDidChange(_ notification: Notification) {
+            guard let textView = notification.object as? NSTextView else {
+                return
+            }
+            parent.text = textView.string
+        }
+    }
+
+    public func makeCoordinator() -> Coordinator {
+        Coordinator(self)
+    }
+
+    public func makeNSView(context: Context) -> NSScrollView {
+        let nsView = NSTextView.scrollableTextView()
+        let textView = nsView.documentView as! NSTextView
+        textView.delegate = context.coordinator
+        textView.textContainerInset = .init(width: 10.0, height: 10.0)
+        nsView.documentView = textView
+        return nsView
+    }
+
+    public func updateNSView(_ nsView: NSScrollView, context: Context) {
+        (nsView.documentView as! NSTextView).string = text
+    }
+
+    public func sizeThatFits(_ proposal: ProposedViewSize, nsView: NSScrollView, context: Context) -> CGSize? {
+        let textView = nsView.documentView as! NSTextView
+        guard let textLayoutManager = textView.textLayoutManager else {
+            return nil
+        }
+        let rect = textLayoutManager.usageBoundsForTextContainer
+        print(rect)
+        let width = proposal.width ?? 0.0
+        let height = rect.height + textView.textContainerInset.height * 2
+        return CGSize(width: width, height: height)
+    }
+}
+
+struct MainView: View {
+    @State
+    private var text: String = "This is sample text.\nHello, World!"
+
+    var body: some View {
+        VStack {
+            ScrollView {
+                LazyVStack {
+                    ForEach(Array(0..<100), id: \.self) { id in
+                        Text("\(id)")
+                    }
+                }
+            }
+            .border(.blue)
+
+            TextView(text: $text)
+                .border(.red)
+                .fixedSize(horizontal: false, vertical: true)
+        }
+        .scenePadding()
+    }
+}
+
+#Preview {
+    MainView()
+}