I'm pretty new to macOS and swift development and I have been watching a few tutorials to figure this out. I also watched a udemy course that worked on 18 macOS projects which got me nowhere

All I want to do is a macOS menu bar app that will add a cursor highlight that should look something like:

I could get the cursor changed to an image doing the following

import SpriteKit

class CursorView: SKView {
    override func resetCursorRects() {
        if let targetImage = NSImage(named: "cursor") {
            let cursor = NSCursor(image: targetImage, 
                                  hotSpot: CGPoint(x: targetImage.size.width / 2, 
                                                   y: targetImage.size.height / 2))
            addCursorRect(frame, cursor: cursor)
        }
    }
}

Three things wrong with this:

1. SKView is a class from SpriteKit and I don't think I should use that for my use-case
2. This calls the addCursorRect that add the changes to a window frame (I need to all the time regardless of the frame)
3. I can't have 100's of images for each style I would set in the future for the highlight color, size, or opacity

So, I'm here trying to understand how I can do this for a menu bar app that should be available on all screens and achieve a highlight as should in the above picture

Not sure if this matters but I'm using storyboard and don't mind switching to SwiftUI

I could really use some help from the community on this. Thank you

CodePudding user response：

You can annotate the system mouse by drawing something around it. This can be done by

• adding an CGEvent tap to capture mouse events
• drawing the annotation around the cursor using a custom window

Here is a simple example application

import SwiftUI

@main
class AppDelegate: NSObject, NSApplicationDelegate {

    var mouseTap: CFMachPort?
    private var window: NSWindow = {
        // Create the SwiftUI view that provides the window contents.
        let contentView = Circle()
            .stroke(lineWidth: 2)
            .foregroundColor(.blue)
            .frame(width: 30, height: 30)
            .padding(2)

        // Create the window and set the content view.
        let window = NSWindow(
            contentRect: NSRect(x: 0, y: 0, width: 34, height: 34),
            styleMask: [.borderless],
            backing: .buffered,
            defer: false
        )
        window.contentView = NSHostingView(rootView: contentView)
        window.backgroundColor = .clear
        window.level = NSWindow.Level.statusBar
        window.makeKeyAndOrderFront(nil)
        return window
    }()

    func applicationDidFinishLaunching(_ aNotification: Notification) {
        if let tap = createMouseTap() {
            if CGEvent.tapIsEnabled(tap: tap) {
                let runLoopSource = CFMachPortCreateRunLoopSource(kCFAllocatorDefault, tap, 0)
                CFRunLoopAddSource(CFRunLoopGetCurrent(), runLoopSource, CFRunLoopMode.commonModes)
                mouseTap = tap
            } else {
                print("tap not enabled")
                mouseTap = nil
            }
        } else {
            print("tap not enabled")
        }
    }

    func createMouseTap() -> CFMachPort? {
        withUnsafeMutableBytes(of: &window) { pointer in
            CGEvent.tapCreate(
                tap: .cgSessionEventTap,
                place: .headInsertEventTap,
                options: CGEventTapOptions.listenOnly,
                eventsOfInterest: (1 << CGEventType.mouseMoved.rawValue | 1 << CGEventType.leftMouseDragged.rawValue),
                callback: mouseMoved,
                userInfo: pointer.baseAddress
            )
        }
    }
}

func mouseMoved(proxy: CGEventTapProxy, type: CGEventType, event: CGEvent, context: UnsafeMutableRawPointer?) -> Unmanaged<CGEvent>? {
    let window = context!.assumingMemoryBound(to: NSWindow.self).pointee
    // using CGPoint SIMD extension from https://gist.github.com/Dev1an/7973cee9d960479b35b705f88b7f38c4
    window.setFrameOrigin(event.unflippedLocation - 17)
    return nil
}

Drawback

Note that this implementation does require the user to allow the keyboard input option in "Universal Access" in "System Preferences".