QR Code

Overview

HudQRCode and HudQRScanner are paired primitives for QR pairing flows. Generation is cross-platform (iOS + macOS) via CoreImage. Scanning is iOS-only via AVCaptureSession — macOS shows an empty-state placeholder. Import from HudsonUI.

HudQRCode

Generates a QR via CIQRCodeGenerator, recolors via CIFalseColor, and renders as a sharp Image with .interpolation(.none) so the pixel grid stays crisp at any size.

struct PairingShareView: View {
    let pairingURL: String

    var body: some View {
        HudQRCode(
            pairingURL,
            size: 240,
            errorCorrection: .high
        )
    }
}

Init parameters

Name	Type	Default	Description
`content`	`String`	—	The string to encode. Empty content renders an error placeholder.
`size`	`CGFloat`	`HudLayout.qrCodeDefault` (200)	Width + height in points.
`foreground`	`Color`	`HudPalette.ink`	Module color.
`background`	`Color`	`HudPalette.surface`	Background fill.
`errorCorrection`	`ErrorCorrection`	`.medium`	`.low` (~7%), `.medium` (~15%), `.quartile` (~25%), `.high` (~30%). Pick `.high` when printed, photographed, or overlaid with a logo.

The view is accessibility-aware: it announces as "QR code" with the encoded content as its value.

HudQRScanner

Wraps AVCaptureSession with a viewfinder overlay, debounces duplicate scans within 1.5s, and triggers a haptic on each accepted code.

struct PairingScanView: View {
    var body: some View {
        HudPermissionGate(.camera, rationale: "Scan a pairing QR to link this device.") {
            HudQRScanner { code in
                pair(with: code)
            }
        }
    }
}

The scanner assumes camera access is granted — calling it without permission yields a black preview, never a crash. Always wrap with HudPermissionGate(.camera, …) so denial flows render the Settings deep-link automatically. See Permissions.

Init parameters

Name	Type	Default	Description
`isActive`	`Bool`	`true`	Toggle the capture session. Set `false` off-screen to release the camera.
`showsViewfinder`	`Bool`	`true`	Overlay corner brackets + centered cutout in a scrim.
`onScan`	`(String) -> Void`	—	Called on the main queue with each accepted scan.

Platform behavior

iOS renders a live preview with viewfinder, orientation tracking, and haptic feedback. macOS renders a HudEmptyState reading "QR scanner unavailable".

Don't forget NSCameraUsageDescription in your Info.plist — HudPermission.camera.infoPlistKey returns the exact key.