Swift – macOS `batteryLevel` property - swift

Question

In iOS there's a simple approach to get a level of iPhone battery:
UIDevice.current.batteryLevel
What's a macOS batteryLevel equivalent for MacBooks?

Answer 1

Getting the battery level in macOS is not as easy as in iOS, but it is still pretty easy. You have to use the IOKit framework for this.
You can use this code to read almost all of the important information from the internal battery.
InternalBattery.swift
import Foundation
import IOKit.ps
public class InternalBattery {
public var name: String?
public var timeToFull: Int?
public var timeToEmpty: Int?
public var manufacturer: String?
public var manufactureDate: Date?
public var currentCapacity: Int?
public var maxCapacity: Int?
public var designCapacity: Int?
public var cycleCount: Int?
public var designCycleCount: Int?
public var acPowered: Bool?
public var isCharging: Bool?
public var isCharged: Bool?
public var amperage: Int?
public var voltage: Double?
public var watts: Double?
public var temperature: Double?
public var charge: Double? {
get {
if let current = self.currentCapacity,
let max = self.maxCapacity {
return (Double(current) / Double(max)) * 100.0
}
return nil
}
}
public var health: Double? {
get {
if let design = self.designCapacity,
let current = self.maxCapacity {
return (Double(current) / Double(design)) * 100.0
}
return nil
}
}
public var timeLeft: String {
get {
if let isCharging = self.isCharging {
if let minutes = isCharging ? self.timeToFull : self.timeToEmpty {
if minutes <= 0 {
return "-"
}
return String(format: "%.2d:%.2d", minutes / 60, minutes % 60)
}
}
return "-"
}
}
public var timeRemaining: Int? {
get {
if let isCharging = self.isCharging {
return isCharging ? self.timeToFull : self.timeToEmpty
}
return nil
}
}
}
InternalFinder.swift:
import Foundation
import IOKit.ps
public class InternalFinder {
private var serviceInternal: io_connect_t = 0 // io_object_t
private var internalChecked: Bool = false
private var hasInternalBattery: Bool = false
public init() { }
public var batteryPresent: Bool {
get {
if !self.internalChecked {
let snapshot = IOPSCopyPowerSourcesInfo().takeRetainedValue()
let sources = IOPSCopyPowerSourcesList(snapshot).takeRetainedValue() as Array
self.hasInternalBattery = sources.count > 0
self.internalChecked = true
}
return self.hasInternalBattery
}
}
fileprivate func open() {
self.serviceInternal = IOServiceGetMatchingService(kIOMasterPortDefault, IOServiceMatching("AppleSmartBattery"))
}
fileprivate func close() {
IOServiceClose(self.serviceInternal)
IOObjectRelease(self.serviceInternal)
self.serviceInternal = 0
}
public func getInternalBattery() -> InternalBattery? {
self.open()
if self.serviceInternal == 0 {
return nil
}
let battery = self.getBatteryData()
self.close()
return battery
}
fileprivate func getBatteryData() -> InternalBattery {
let battery = InternalBattery()
let snapshot = IOPSCopyPowerSourcesInfo().takeRetainedValue()
let sources = IOPSCopyPowerSourcesList(snapshot).takeRetainedValue() as Array
for ps in sources {
// Fetch the information for a given power source out of our snapshot
let info = IOPSGetPowerSourceDescription(snapshot, ps).takeUnretainedValue() as! Dictionary<String, Any>
// Pull out the name and capacity
battery.name = info[kIOPSNameKey] as? String
battery.timeToEmpty = info[kIOPSTimeToEmptyKey] as? Int
battery.timeToFull = info[kIOPSTimeToFullChargeKey] as? Int
}
// Capacities
battery.currentCapacity = self.getIntValue("CurrentCapacity" as CFString)
battery.maxCapacity = self.getIntValue("MaxCapacity" as CFString)
battery.designCapacity = self.getIntValue("DesignCapacity" as CFString)
// Battery Cycles
battery.cycleCount = self.getIntValue("CycleCount" as CFString)
battery.designCycleCount = self.getIntValue("DesignCycleCount9C" as CFString)
// Plug
battery.acPowered = self.getBoolValue("ExternalConnected" as CFString)
battery.isCharging = self.getBoolValue("IsCharging" as CFString)
battery.isCharged = self.getBoolValue("FullyCharged" as CFString)
// Power
battery.amperage = self.getIntValue("Amperage" as CFString)
battery.voltage = self.getVoltage()
// Various
battery.temperature = self.getTemperature()
// Manufaction
battery.manufacturer = self.getStringValue("Manufacturer" as CFString)
battery.manufactureDate = self.getManufactureDate()
if let amperage = battery.amperage,
let volts = battery.voltage, let isCharging = battery.isCharging {
let factor: CGFloat = isCharging ? 1 : -1
let watts: CGFloat = (CGFloat(amperage) * CGFloat(volts)) / 1000.0 * factor
battery.watts = Double(watts)
}
return battery
}
fileprivate func getIntValue(_ identifier: CFString) -> Int? {
if let value = IORegistryEntryCreateCFProperty(self.serviceInternal, identifier, kCFAllocatorDefault, 0) {
return value.takeRetainedValue() as? Int
}
return nil
}
fileprivate func getStringValue(_ identifier: CFString) -> String? {
if let value = IORegistryEntryCreateCFProperty(self.serviceInternal, identifier, kCFAllocatorDefault, 0) {
return value.takeRetainedValue() as? String
}
return nil
}
fileprivate func getBoolValue(_ forIdentifier: CFString) -> Bool? {
if let value = IORegistryEntryCreateCFProperty(self.serviceInternal, forIdentifier, kCFAllocatorDefault, 0) {
return value.takeRetainedValue() as? Bool
}
return nil
}
fileprivate func getTemperature() -> Double? {
if let value = IORegistryEntryCreateCFProperty(self.serviceInternal, "Temperature" as CFString, kCFAllocatorDefault, 0) {
return value.takeRetainedValue() as! Double / 100.0
}
return nil
}
fileprivate func getDoubleValue(_ identifier: CFString) -> Double? {
if let value = IORegistryEntryCreateCFProperty(self.serviceInternal, identifier, kCFAllocatorDefault, 0) {
return value.takeRetainedValue() as? Double
}
return nil
}
fileprivate func getVoltage() -> Double? {
if let value = getDoubleValue("Voltage" as CFString) {
return value / 1000.0
}
return nil
}
fileprivate func getManufactureDate() -> Date? {
if let value = IORegistryEntryCreateCFProperty(self.serviceInternal, "ManufactureDate" as CFString, kCFAllocatorDefault, 0) {
let date = value.takeRetainedValue() as! Int
let day = date & 31
let month = (date >> 5) & 15
let year = ((date >> 9) & 127) + 1980
var components = DateComponents()
components.calendar = Calendar.current
components.day = day
components.month = month
components.year = year
return components.date
}
return nil
}
}
Usage:
let internalFinder = InternalFinder()
if let internalBattery = internalFinder.getInternalBattery() {
// Internal battery found, access properties here.
}