Device Hardware

The SkipDevice module is a dual-platform Skip framework that provides access to network reachability, location, and device sensor data.

Setup

To include this framework in your project, add the following dependency to your Package.swift file:

let package = Package(
    name: "my-package",
    products: [
        .library(name: "MyProduct", targets: ["MyTarget"]),
    ],
    dependencies: [
        .package(url: "https://source.skip.tools/skip-device.git", "0.0.0"..<"2.0.0"),
    ],
    targets: [
        .target(name: "MyTarget", dependencies: [
            .product(name: "SkipDevice", package: "skip-device")
        ])
    ]
)

Network Reachability

You can check whether the device is currenly able to access the network with:

let isReachable: Bool = networkReachability.isNetworkReachable

Network Reachability Permissions

In order to access the device’s photos or media library, you will need to declare the permissions in the app’s metadata.

On Android, the app/src/main/AndroidManifest.xml file will need to be edited to include:

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

Location

You can request a single current device location with:

let provider = LocationProvider()
let location: LocationEvent = try await provider.fetchCurrentLocation()
logger.log("latitude: \(location.latitude) longitude: \(location.longitude) altitude: \(location.altitude)")

You can also subscribe to a stream of location updates like so:

import SwiftUI
import SkipKit // for PermissionManager
import SkipDevice

struct LocationView : View {
    @State var event: LocationEvent?

    var body: some View {
        VStack {
            if let event = event {
                Text("latitude: \(event.latitude)")
                Text("longitude: \(event.longitude)")
                Text("altitude: \(event.altitude)")
                Text("course: \(event.course)")
                Text("speed: \(event.speed)")
            }
        }
        .font(Font.body.monospaced())
        .task {
            // SkipKit provided PermissionManager, which creates a user-interface to request individual permissions
            if await PermissionManager.requestLocationPermission(precise: true, always: false).isAuthorized == false {
                logger.warning("permission refused for ACCESS_FINE_LOCATION")
                return
            }

            let provider = LocationProvider() // must retain reference
            provider.updateInterval = 1.0
            do {
                for try await event in provider.monitor() {
                    self.event = event
                    // if cancelled { break }
                }
            } catch {
                logger.error("error updating location: \(error)")
            }
            provider.stop()
        }
    }
}

Location Permissions

In order to access the device’s location, you will need to declare the permissions in the app’s metadata.

On Android, the app/src/main/AndroidManifest.xml file will need to be edited to include one of the following permissions:

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>

On iOS, you will need to add the NSLocationWhenInUseUsageDescription key to your Darwin/AppName.xcconfig file:

INFOPLIST_KEY_NSLocationWhenInUseUsageDescription = "This app uses your location to …"

Motion

Motion Permissions

On iOS, you will need to add the NSMotionUsageDescription key to your Darwin/AppName.xcconfig file:

INFOPLIST_KEY_NSMotionUsageDescription = "This app uses your motion information to …"

Accelerometer

The AccelerometerProvider type provides an AsyncThrowingStream<AccelerometerEvent, Event> of device accelerometer changes.

It can be used in a View like this:

import SwiftUI
import SkipDevice

struct AccelerometerView : View {
    @State var event: AccelerometerEvent?

    var body: some View {
        VStack {
            if let event = event {
                Text("x: \(event.x)")
                Text("y: \(event.y)")
                Text("z: \(event.z)")
            }
        }
        .task {
            let provider = AccelerometerProvider() // must retain reference
            provider.updateInterval = 0.1
            do {
                for try await event in provider.monitor() {
                    self.event = event
                    // if cancelled { break }
                }
            } catch {
                logger.error("error updating accelerometer: \(error)")
            }
            provider.stop()
        }
    }
}

Gyroscope

The GyroscopeProvider type provides an AsyncThrowingStream<GyroscopeEvent, Event> of device gyroscope changes.

It can be used in a View like this:

import SwiftUI
import SkipDevice

struct GyroscopeView : View {
    @State var event: GyroscopeEvent?

    var body: some View {
        VStack {
            if let event = event {
                Text("x: \(event.x)")
                Text("y: \(event.y)")
                Text("z: \(event.z)")
            }
        }
        .task {
            let provider = GyroscopeProvider() // must retain reference
            provider.updateInterval = 0.1
            do {
                for try await event in provider.monitor() {
                    self.event = event
                    // if cancelled { break }
                }
            } catch {
                logger.error("error updating gyroscope: \(error)")
            }
            provider.stop()
        }
    }
}

Magnetometer

The MagnetometerProvider type provides an AsyncThrowingStream<MagnetometerEvent, Error> of device magnetometer changes.

It can be used in a View like this:

import SwiftUI
import SkipDevice

struct MagnetometerView : View {
    @State var event: MagnetometerEvent?

    var body: some View {
        VStack {
            if let event = event {
                Text("x: \(event.x)") // X-axis magnetic field in microteslas
                Text("y: \(event.y)") // Y-axis magnetic field in microteslas
                Text("z: \(event.z)") // Z-axis magnetic field in microteslas
            }
        }
        .font(Font.body.monospaced())
        .task {
            let provider = MagnetometerProvider() // must retain reference
            provider.updateInterval = 0.1
            do {
                for try await event in provider.monitor() {
                    self.event = event
                    // if cancelled { break }
                }
            } catch {
                logger.error("error updating magnetometer: \(error)")
            }
            provider.stop()
        }
    }
}

Barometer

The BarometerProvider type provides an AsyncThrowingStream<BarometerEvent, Event> of device barometer changes.

It can be used in a View like this:

import SwiftUI
import SkipDevice

struct BarometerView : View {
    @State var event: BarometerEvent?

    var body: some View {
        VStack {
            if let event = event {
                Text("pressure: \(event.pressure)") // The recorded pressure, in kilopascals.
                Text("relativeAltitude: \(event.relativeAltitude)") // The change in altitude (in meters) since the first reported event.
            }
        }
        .font(Font.body.monospaced())
        .task {
            let provider = BarometerProvider() // must retain reference
            provider.updateInterval = 0.1
            do {
                for try await event in provider.monitor() {
                    self.event = event
                    // if cancelled { break }
                }
            } catch {
                logger.error("error updating barometer: \(error)")
            }
            provider.stop()
        }
    }
}

Barometer Permissions

In order to access the device’s barometer, you will need to declare the permissions in the app’s metadata.

On Android, the app/src/main/AndroidManifest.xml file will need to be edited to include:

<uses-feature android:name="android.hardware.sensor.barometer" android:required="true" />

Building

This project is a Swift Package Manager module that uses the Skip plugin to transpile Swift into Kotlin.

Building the module requires that Skip be installed using Homebrew ↗ with brew install skiptools/skip/skip. This will also install the necessary build prerequisites: Kotlin, Gradle, and the Android build tools.

Testing

The module can be tested using the standard swift test command or by running the test target for the macOS destination in Xcode, which will run the Swift tests as well as the transpiled Kotlin JUnit tests in the Robolectric Android simulation environment.

Parity testing can be performed with skip test, which will output a table of the test results for both platforms.

Contributing

We welcome contributions to this package in the form of enhancements and bug fixes.

The general flow for contributing to this and any other Skip package is:

Fork this repository and enable actions from the “Actions” tab
Check out your fork locally
When developing alongside a Skip app, add the package to a shared workspace to see your changes incorporated in the app
Push your changes to your fork and ensure the CI checks all pass in the Actions tab
Add your name to the Skip Contributor Agreement ↗
Open a Pull Request from your fork with a description of your changes