# WhereIsMyMac

- `Download example`

This example shows how to use the CoreLocation framework and is a translation in Python of the example at “Cocoa with Love”

## Sources

### WhereIsMyMacAppDelegate.py

    """
    This file is a translation from Objective-C. The original
    copy-right:

    //  Copyright 2009 Matt Gallagher. All rights reserved.
    //
    //  Permission is given to use this source code file, free of charge, in any
    //  project, commercial or otherwise, entirely at your risk, with the condition
    //  that any redistribution (in part or whole) of source code must retain
    //  this copyright and permission notice. Attribution in compiled projects is
    //  appreciated but not required.
    """

    import math

    import Cocoa
    import WebKit  # noqa: F401
    import CoreLocation
    import objc

    class WhereIsMyMacAppDelegate(Cocoa.NSObject):
        window = objc.ivar()
        webView = objc.IBOutlet()
        locationManager = objc.ivar()
        locationLabel = objc.IBOutlet()
        accuracyLabel = objc.IBOutlet()

        def applicationDidFinishLaunching_(self, notification):
            self.locationManager = CoreLocation.CLLocationManager.alloc().init()
            self.locationManager.setDelegate_(self)
            self.locationManager.startUpdatingLocation()

        @classmethod
        def latitudeRangeForLocation_(self, location):
            M = 6_367_000.0
            # approximate average meridional radius of curvature of earth
            metersToLatitude = 1.0 / ((math.pi / 180.0) * M)
            accuracyToWindowScale = 2.0

            return location.horizontalAccuracy() * metersToLatitude * accuracyToWindowScale

        @classmethod
        def longitudeRangeForLocation_(self, location):
            latitudeRange = WhereIsMyMacAppDelegate.latitudeRangeForLocation_(location)

            return latitudeRange * math.cos(
                location.coordinate().latitude * math.pi / 180.0
            )

        @objc.IBAction
        def openInDefaultBrowser_(self, sender):
            currentLocation = self.locationManager.location()

            externalBrowserURL = Cocoa.NSURL.URLWithString_(
                "http://maps.google.com/maps?ll=%f,%f&amp;spn=%f,%f"
                % (
                    currentLocation.coordinate().latitude,
                    currentLocation.coordinate().longitude,
                    WhereIsMyMacAppDelegate.latitudeRangeForLocation_(currentLocation),
                    WhereIsMyMacAppDelegate.longitudeRangeForLocation_(currentLocation),
                )
            )

            Cocoa.NSWorkspace.sharedWorkspace().openURL_(externalBrowserURL)

        def locationManager_didUpdateToLocation_fromLocation_(
            self, manager, newLocation, oldLocation
        ):
            # Ignore updates where nothing we care about changed
            if newLocation is None:
                return
            if oldLocation is None:
                pass
            elif (
                newLocation.coordinate().longitude == oldLocation.coordinate().longitude
                and newLocation.coordinate().latitude == oldLocation.coordinate().latitude
                and newLocation.horizontalAccuracy() == oldLocation.horizontalAccuracy()
            ):
                return

            # Load the HTML for displaying the Google map from a file and replace the
            # format placeholders with our location data
            path = Cocoa.NSBundle.mainBundle().pathForResource_ofType_(
                "HTMLFormatString", "html"
            )
            with open(path) as fp:
                htmlString = fp.read() % (
                    newLocation.coordinate().latitude,
                    newLocation.coordinate().longitude,
                    WhereIsMyMacAppDelegate.latitudeRangeForLocation_(newLocation),
                    WhereIsMyMacAppDelegate.longitudeRangeForLocation_(newLocation),
                )

            # Load the HTML in the WebView and set the labels
            self.webView.mainFrame().loadHTMLString_baseURL_(htmlString, None)
            self.locationLabel.setStringValue_(
                "%f, %f"
                % (newLocation.coordinate().latitude, newLocation.coordinate().longitude)
            )
            self.accuracyLabel.setStringValue_(f"{newLocation.horizontalAccuracy():f}")

        def locationManager_didFailWithError_(self, manager, error):
            self.webView.mainFrame.loadHTMLString_baseURL_(
                Cocoa.NSLocalizedString("Location manager failed with error: %s", objc.nil)
                % (error.localizedDescription()),
                None,
            )
            self.locationLabel.setStringValue_("")
            self.accuracyLabel.setStringValue_("")

        def applicationWillTerminate_(self, aNotification):
            self.locationManager.stopUpdatingLocation()

### main.py

    import WhereIsMyMacAppDelegate  # noqa: F401
    from PyObjCTools import AppHelper

    AppHelper.runEventLoop()

### setup.py

    """
    Script for building the example.

    Usage:
        python3 setup.py py2app
    """
    from setuptools import setup

    setup(
        name="WhereIsMyMac",
        app=["main.py"],
        data_files=["English.lproj", "HTMLFormatString.html"],
        setup_requires=[
            "py2app",
            "pyobjc-framework-Cocoa",
            "pyobjc-framework-CoreLocation",
        ],
    )