Implement CALayer drag preview for 5.2.0

Ariver

2026-05-11 1a7643b2e7e8f9712533e5a68536ee3b23b0804b

Implement CALayer drag preview for 5.2.0

 Apptag/AppDragCoordinator.swift

@@ -1,5 +1,6 @@
import SwiftUI
import AppKit
import QuartzCore

final class AppDragCoordinator {
    static let shared = AppDragCoordinator()
@@ -12,8 +13,11 @@

    private var targets: [UUID: DropTarget] = [:]
    private weak var dragHostWindow: NSWindow?
    private weak var dragPreviewSuperview: NSView?
    private var dragPreviewView: DragPreviewView?
    private weak var dragLayerHostView: NSView?
    private var dragLayer: CALayer?
    private var normalDragImage: CGImage?
    private var copyDragImage: CGImage?
    private var currentCopyMode = false
    private var dragWindow: NSWindow?
    private var dragImageSize: NSSize = .zero
    private var activePayload = ""
@@ -33,19 +37,15 @@
        activePayload = payload
        dragImageSize = image.size
        dragHostWindow = hostWindow
        currentCopyMode = copy
        normalDragImage = Self.cgImage(from: image)
        copyDragImage = Self.cgImage(from: Self.copyBadgeImage(from: image))

        let hostView: NSView

        if let contentView = hostWindow?.contentView {
            let preview = DragPreviewView(image: image, copy: copy, frame: NSRect(origin: .zero, size: image.size))
            preview.translatesAutoresizingMaskIntoConstraints = true
            preview.autoresizingMask = []
            contentView.addSubview(preview, positioned: .above, relativeTo: nil)
            preview.layer?.zPosition = 1_000_000
            dragPreviewSuperview = contentView
            dragPreviewView = preview
            updateDragLocation(screenPoint)
            return
        }

            hostView = contentView
        } else {
        let panel = NSPanel(
            contentRect: NSRect(origin: .zero, size: image.size),
            styleMask: [.borderless, .nonactivatingPanel],
@@ -61,28 +61,49 @@
        panel.level = NSWindow.Level(rawValue: Int(CGWindowLevelForKey(.maximumWindow)))
        panel.collectionBehavior = [.moveToActiveSpace, .fullScreenAuxiliary, .stationary, .transient, .ignoresCycle]
        panel.isReleasedWhenClosed = false

        panel.contentView = DragPreviewView(image: image, copy: copy, frame: NSRect(origin: .zero, size: image.size))

            let contentView = NSView(frame: NSRect(origin: .zero, size: image.size))
            panel.contentView = contentView
        dragWindow = panel
        updateDragLocation(screenPoint)
        panel.setFrame(panel.frame, display: true)
            dragHostWindow = panel
            hostView = contentView
            panel.setFrameOrigin(NSPoint(x: screenPoint.x - image.size.width / 2, y: screenPoint.y - image.size.height / 2))
        panel.orderFrontRegardless()
    }

        hostView.wantsLayer = true
        guard let rootLayer = hostView.layer else { return }

        let layer = CALayer()
        layer.bounds = CGRect(origin: .zero, size: image.size)
        layer.anchorPoint = CGPoint(x: 0.5, y: 0.5)
        layer.contentsGravity = .resizeAspect
        layer.contentsScale = NSScreen.main?.backingScaleFactor ?? 2
        layer.contents = copy ? copyDragImage : normalDragImage
        layer.zPosition = 1_000_000
        layer.actions = [
            "position": NSNull(),
            "contents": NSNull(),
            "bounds": NSNull(),
            "opacity": NSNull()
        ]

        rootLayer.addSublayer(layer)
        dragLayerHostView = hostView
        dragLayer = layer
        updateDragLocation(screenPoint)
    }

    func updateDragLocation(_ screenPoint: NSPoint, copy: Bool? = nil) {
        if let dragPreviewView, let dragHostWindow, let contentView = dragPreviewSuperview {
        if let dragLayer, let dragHostWindow, let hostView = dragLayerHostView {
            if let copy {
                dragPreviewView.isCopyMode = copy
                updateCopyMode(copy)
            }
            let windowPoint = dragHostWindow.convertPoint(fromScreen: screenPoint)
            let contentPoint = contentView.convert(windowPoint, from: nil)
            dragPreviewView.setFrameOrigin(
                NSPoint(
                    x: contentPoint.x - dragImageSize.width / 2,
                    y: contentPoint.y - dragImageSize.height / 2
                )
            )
            let contentPoint = hostView.convert(windowPoint, from: nil)
            CATransaction.begin()
            CATransaction.setDisableActions(true)
            dragLayer.position = contentPoint
            CATransaction.commit()
            return
        }

@@ -115,53 +136,43 @@
        endDragVisuals()
    }

    private func updateCopyMode(_ copy: Bool) {
        guard currentCopyMode != copy else { return }
        currentCopyMode = copy
        CATransaction.begin()
        CATransaction.setDisableActions(true)
        dragLayer?.contents = copy ? copyDragImage : normalDragImage
        CATransaction.commit()
    }

    private func endDragVisuals() {
        dragPreviewView?.removeFromSuperview()
        dragPreviewView = nil
        dragPreviewSuperview = nil
        dragLayer?.removeFromSuperlayer()
        dragLayer = nil
        dragLayerHostView = nil
        dragHostWindow = nil
        normalDragImage = nil
        copyDragImage = nil
        currentCopyMode = false
        dragWindow?.orderOut(nil)
        dragWindow = nil
        activePayload = ""
        dragImageSize = .zero
    }

    private static func cgImage(from image: NSImage) -> CGImage? {
        var rect = NSRect(origin: .zero, size: image.size)
        return image.cgImage(forProposedRect: &rect, context: nil, hints: [
            .interpolation: NSImageInterpolation.high
        ])
}

private final class DragPreviewView: NSView {
    private let image: NSImage
    var isCopyMode: Bool {
        didSet {
            if oldValue != isCopyMode {
                needsDisplay = true
            }
        }
    }
    private static func copyBadgeImage(from baseImage: NSImage) -> NSImage {
        let image = NSImage(size: baseImage.size)
        image.lockFocus()
        NSGraphicsContext.current?.imageInterpolation = .high
        baseImage.draw(in: NSRect(origin: .zero, size: baseImage.size), from: .zero, operation: .sourceOver, fraction: 1)

    init(image: NSImage, copy: Bool, frame: NSRect) {
        self.image = image
        self.isCopyMode = copy
        super.init(frame: frame)
        wantsLayer = true
        layer?.masksToBounds = false
    }

    required init?(coder: NSCoder) {
        nil
    }

    override var isOpaque: Bool { false }

    override func hitTest(_ point: NSPoint) -> NSView? {
        nil
    }

    override func draw(_ dirtyRect: NSRect) {
        NSColor.clear.setFill()
        dirtyRect.fill()
        image.draw(in: bounds, from: .zero, operation: .sourceOver, fraction: 1.0)

        guard isCopyMode else { return }

        let bounds = NSRect(origin: .zero, size: baseImage.size)
        let badgeSize = min(bounds.width, bounds.height) * 0.28
        let badgeRect = NSRect(
            x: bounds.maxX - badgeSize - badgeSize * 0.22,
@@ -193,6 +204,8 @@
            ),
            withAttributes: attrs
        )
        image.unlockFocus()
        return image
    }
}


 Apptag/Info.plist

@@ -19,9 +19,9 @@
    <key>CFBundlePackageType</key>
    <string>APPL</string>
    <key>CFBundleShortVersionString</key>
    <string>5.1.12</string>
    <string>5.2.0</string>
    <key>CFBundleVersion</key>
    <string>12</string>
    <string>13</string>
    <key>LSMinimumSystemVersion</key>
    <string>15.0</string>
    <key>NSHighResolutionCapable</key>