Fetch the battery status of my MacBook with Swift - macos

Question

I want to setup a Playground to fetch the battery status of my macbook.
I have already tried the following:
import Cocoa
import IOKit
import Foundation
var blob = IOPSCopyPowerSourcesInfo()
I am currently receiving an error as below
Use of unresolved identifier 'IOPSCopyPowerSourcesInfo'

Answer 1

It doesn't work in a Playground, but it works in a real app.
I couldn't access the IOPowerSources.h header file with Swift and import IOKit only, though: I had to make a bridge to Objective-C.
Here's my solution:
Add IOKit.framework to your project (click + in Linked Frameworks and Libraries)
Create a new empty .m file, whatever its name. Xcode will then ask if it should make a "bridging header". Say YES.
Ignore the .m file. In the new YOURAPPNAME-Bridging-Header.h file that Xcode just created, add the line #import <IOKit/ps/IOPowerSources.h> (and don't add import IOKit in your Swift file)
You can now access most of the IOPowerSources functions.
Example:
func getBatteryStatus() -> String {
let timeRemaining: CFTimeInterval = IOPSGetTimeRemainingEstimate()
if timeRemaining == -2.0 {
return "Plugged"
} else if timeRemaining == -1.0 {
return "Recently unplugged"
} else {
let minutes = timeRemaining / 60
return "Time remaining: \(minutes) minutes"
}
}
let batteryStatus = getBatteryStatus()
print(batteryStatus)
Note: I couldn't access constants like kIOPSTimeRemainingUnlimited and kIOPSTimeRemainingUnknown so I used their raw values (-2.0 and -1.0) but it would be better to find these constants if they still exist somewhere.
Another example, with IOPSCopyPowerSourcesInfo:
let blob = IOPSCopyPowerSourcesInfo()
let list = IOPSCopyPowerSourcesList(blob.takeRetainedValue())
print(list.takeRetainedValue())
Result:
(
{
"Battery Provides Time Remaining" = 1;
BatteryHealth = Good;
Current = 0;
"Current Capacity" = 98;
DesignCycleCount = 1000;
"Hardware Serial Number" = 1X234567XX8XX;
"Is Charged" = 1;
"Is Charging" = 0;
"Is Present" = 1;
"Max Capacity" = 100;
Name = "InternalBattery-0";
"Power Source State" = "AC Power";
"Time to Empty" = 0;
"Time to Full Charge" = 0;
"Transport Type" = Internal;
Type = InternalBattery;
}
)