RangeExtender

This little Swift Package helps to connect to a Ranger device and receive range and battery state-of-charge values from it.

Usage

RangeExtender hides the Bluetooth communication and state-handling logic behind a simple Swift API. To receive values from a Ranger device, follow these steps:

1. Add this Package into your project.
2. Declare import RangeExtender.
3. Create a class which adopts the RangeExtenderDelegate and implements its callback methods.
4. Create an instance of RangeExtender and assign your delegate to it.
5. Call start() on the RangeExtender.
6. Observe state and value changes delivered via the delegate.
7. Call stop() to cancel a connection (or connection attempt) to a Ranger device.

A simple usage might thus look like this:

import RangeExtender

class MyRangeExtenderDelegate : RangeExtenderDelegate {
    func rangeExtender(_ rangeExtender: RangeExtender, didChangeState state: RangeExtenderState) {
        print("state: \(state)")
    }
    func rangeExtender(_ rangeExtender: RangeExtender, didReceiveRange range: Int) {
        print("range: \(range)mm")
    }
    func rangeExtender(_ rangeExtender: RangeExtender, didReceiveBattery battery: Int) {
        print("battery: \(battery)%")
    }
}

let rangeExtender = RangeExtender()
let myRangeExtenderDelegate = MyRangeExtenderDelegate()
rangeExtender.delegate = myRangeExtenderDelegate

rangeExtender.start()

Notes

Connecting to a Bluetooth device is a bit tedious as it consists of different phases triggered by various events. Normally, an implementation uses a State-Machine to handle this logic. Here, we use the State-Flow by Control-Flow approach instead which allows to express the logic as a structured synchronous program. This is done with the help of the Pappe Project.