Paperkit

# PaperKit

> **Beta-sensitive.** PaperKit is new in iOS/iPadOS 26, macOS 26, and visionOS 26. API surface may change. Verify details against current Apple documentation before shipping.

PaperKit provides a unified markup experience — the same framework powering markup in Notes, Screenshots, QuickLook, and Journal. It combines PencilKit drawing with structured markup elements (shapes, text boxes, images, lines) in a single canvas managed by `PaperMarkupViewController`. Requires Swift 6.3 and the iOS 26+ SDK.

## Contents

- [Setup](#setup)
- [PaperMarkupViewController](#papermarkupviewcontroller)
- [PaperMarkup Data Model](#papermarkup-data-model)
- [Insertion Controllers](#insertion-controllers)
- [FeatureSet Configuration](#featureset-configuration)
- [Integration with PencilKit](#integration-with-pencilkit)
- [SwiftUI Integration](#swiftui-integration)
- [Common Mistakes](#common-mistakes)
- [Review Checklist](#review-checklist)
- [References](#references)

## Setup

PaperKit requires no entitlements or special Info.plist entries.

```swift
import PaperKit
```

**Platform availability:** iOS 26.0+, iPadOS 26.0+, Mac Catalyst 26.0+, macOS 26.0+, visionOS 26.0+.

Three core components:

| Component | Role |
|---|---|
| `PaperMarkupViewController` | Interactive canvas for creating and displaying markup and drawing |
| `PaperMarkup` | Data model for serializing all markup elements and PencilKit drawing |
| `MarkupEditViewController` / `MarkupToolbarViewController` | Insertion UI for adding markup elements |

## PaperMarkupViewController

The primary view controller for interactive markup. Provides a scrollable canvas for freeform PencilKit drawing and structured markup elements. Conforms to `Observable` and `PKToolPickerObserver`.

### Basic UIKit Setup

```swift
import PaperKit
import PencilKit
import UIKit

class MarkupViewController: UIViewController, PaperMarkupViewController.Delegate {
    var paperVC: PaperMarkupViewController!
    var toolPicker: PKToolPicker!

    override func viewDidLoad() {
        super.viewDidLoad()

        let markup = PaperMarkup(bounds: view.bounds)
        paperVC = PaperMarkupViewController(
            markup: markup,
            supportedFeatureSet: .latest
        )
        paperVC.delegate = self

        addChild(paperVC)
        paperVC.view.frame = view.bounds
        paperVC.view.autoresizingMask = [.flexibleWidth, .flexibleHeight]
        view.addSubview(paperVC.view)
        paperVC.didMove(toParent: self)

        toolPicker = PKToolPicker()
        toolPicker.addObserver(paperVC)
        paperVC.pencilKitResponderState.activeToolPicker = toolPicker
        paperVC.pencilKitResponderState.toolPickerVisibility = .visible
    }

    func paperMarkupViewControllerDidChangeMarkup(
        _ controller: PaperMarkupViewController
    ) {
        guard let markup = controller.markup else { return }
        Task { try await save(markup) }
    }
}
```

### Key Properties

| Property | Type | Description |
|---|---|---|
| `markup` | `PaperMarkup?` | The current data model |
| `selectedMarkup` | `PaperMarkup` | Currently selected content |
| `isEditable` | `Bool` | Whether the canvas accepts input |
| `isRulerActive` | `Bool` | Whether the ruler overlay is shown |
| `drawingTool` | `any PKTool` | Active PencilKit drawing tool |
| `contentView` | `UIView?` / `NSView?` | Background view rendered beneath markup |
| `zoomRange` | `ClosedRange<CGFloat>` | Min/max zoom scale |
| `supportedFeatureSet` | `FeatureSet` | Enabled PaperKit features |

### Touch Modes

`PaperMarkupViewController.TouchMode` has two cases: `.drawing`