public int Compare(object x, object y)
{
ObservableBluetoothLEDevice a = x as ObservableBluetoothLEDevice;
ObservableBluetoothLEDevice b = y as ObservableBluetoothLEDevice;
if (a == null || b == null)
{
throw new InvalidOperationException("Compared objects are not ObservableBluetoothLEDevice");
}
// If they're equal
if (a.RSSI == b.RSSI)
{
return(0);
}
// RSSI == 0 means we don't know it. Always make that the end.
if (b.RSSI == 0)
{
return(-1);
}
if (a.RSSI < b.RSSI || a.rssi == 0)
{
return(1);
}
else
{
return(-1);
}
}
/// <summary>
/// Update the battery level of a ObservableBluetoothLEDevice by searching through known dev nodes
/// </summary>
/// <param name="dev">device to update</param>
/// <returns></returns>
private async Task UpdateBatteryLevel(ObservableBluetoothLEDevice dev)
{
foreach (DeviceInformation devNode in devNodes)
{
string addr = dev.BluetoothAddressAsString.Replace(":", String.Empty);
if (devNode.Properties.Keys.Contains(BatteryLevelGUID) &&
devNode.Properties[BatteryLevelGUID] != null &&
devNode.Properties.Keys.Contains(BluetoothDeviceAddress) &&
devNode.Properties[BluetoothDeviceAddress] != null)
{
if ((string)devNode.Properties[BluetoothDeviceAddress] == addr)
{
await Windows.ApplicationModel.Core.CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(
Windows.UI.Core.CoreDispatcherPriority.Normal,
() =>
{
dev.BatteryLevel = Convert.ToInt32((byte)devNode.Properties[BatteryLevelGUID]);
});
break;
}
}
}
}
/// <summary>
/// Adds the new or updated device to the displayed or unused list
/// </summary>
/// <param name="deviceInfo"></param>
/// <returns></returns>
private async Task AddDeviceToList(DeviceInformation deviceInfo)
{
ObservableBluetoothLEDevice dev = new ObservableBluetoothLEDevice(deviceInfo);
// Let's make it connectable by default, we have error handles in case it doesn't work
bool shouldDisplay =
((dev.DeviceInfo.Properties.Keys.Contains("System.Devices.Aep.Bluetooth.Le.IsConnectable") &&
(bool)dev.DeviceInfo.Properties["System.Devices.Aep.Bluetooth.Le.IsConnectable"])) ||
((dev.DeviceInfo.Properties.Keys.Contains("System.Devices.Aep.IsConnected") &&
(bool)dev.DeviceInfo.Properties["System.Devices.Aep.IsConnected"])) ||
((dev.DeviceInfo.Properties.Keys.Contains("System.Devices.Aep.IsPaired") &&
(bool)dev.DeviceInfo.Properties["System.Devices.Aep.IsPaired"]));
if (shouldDisplay)
{
// Need to lock as another DeviceWatcher might be modifying BluetoothLEDevices
try
{
await BluetoothLEDevicesLock.WaitAsync();
await UpdateBatteryLevel(dev);
if (!BluetoothLEDevices.Contains(dev))
{
await Windows.ApplicationModel.Core.CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(
Windows.UI.Core.CoreDispatcherPriority.Normal,
() =>
{
BluetoothLEDevices.Add(dev);
});
}
}
finally
{
BluetoothLEDevicesLock.Release();
}
}
else
{
try
{
await BluetoothLEDevicesLock.WaitAsync();
unusedDevices.Add(deviceInfo);
}
finally
{
BluetoothLEDevicesLock.Release();
}
}
}