Windows Phone 8 Battery API

The Battery API makes a nice addition to the WP8 SDK.

I can see in the near future that some applications will display the battery metrics on a Live Tile or in the application that hides the System Tray.

The Battery API is pretty easy to use:

1. Get the Battery instance with Battery.GetDefault()
2. Bind to the event RemainingChargePercentChanged.

The battery properties are:

• RemainingChargePercent: gets a value that indicates the percentage of the charge remaining on the phone’s battery
• RemainingDischargeTime: gets a value that estimates how much time is left until the phone’s battery is fully discharged. 

With the following code:

using Windows.Phone.Devices.Power;

namespace BatteryApp
{
    public partial class MainPage
    {
        private readonly Battery _battery;

        public MainPage()
        {
            InitializeComponent();

            _battery = Battery.GetDefault();

            _battery.RemainingChargePercentChanged += OnRemainingChargePercentChanged;

            UpdateUI();
        }

        private void OnRemainingChargePercentChanged(object sender, object e)
        {
            UpdateUI();
        }

        private void UpdateUI()
        {
            textBlockRemainingCharge.Text = string.Format("{0} %", _battery.RemainingChargePercent);
            textBlockDischargeTime.Text = string.Format("{0} minutes", _battery.RemainingDischargeTime.TotalMinutes);
        }
    }
}

Please note that when running this on the emulator, it  will show 100% and an infinite discharge time. The above values are fake.