private void StartWatcher()
{
DeviceWatcherEventKind[] triggerEventKinds = { DeviceWatcherEventKind.Add, DeviceWatcherEventKind.Remove /*, DeviceWatcherEventKind.Update */ };
//IEnumerable<DeviceWatcherEventKind> triggerEventKinds = DeviceWatcherEventKind.Add;
DeviceWatcher deviceWatcher = null;
string selector = SmartCardReader.GetDeviceSelector();
selector += " AND System.Devices.DeviceInstanceId:~~\"Ledger\"";
deviceWatcher = DeviceInformation.CreateWatcher(selector, null);
DeviceWatcherTrigger deviceWatcherTrigger = deviceWatcher.GetBackgroundTrigger(triggerEventKinds);
RegisterTask(deviceWatcherTrigger);
}
private async void ToggleSwitch_Toggled(object sender, Windows.UI.Xaml.RoutedEventArgs e)
{
ToggleSwitch toggleSwitch = sender as ToggleSwitch;
if (toggleSwitch != null)
{
var TaskName = "background.Task";
if (toggleSwitch.IsOn == true)
{
var taskRegistered = false;
foreach (var task in BackgroundTaskRegistration.AllTasks)
{
if (task.Value.Name == TaskName)
{
taskRegistered = true;
break;
}
}
if (taskRegistered != true)
{
var builder = new BackgroundTaskBuilder();
builder.Name = TaskName;
builder.TaskEntryPoint = TaskName;
DeviceWatcher deviceWatcher = DeviceInformation.CreateWatcher();
DeviceWatcherEventKind[] triggerEventKinds = { DeviceWatcherEventKind.Add };
IBackgroundTrigger trigger = deviceWatcher.GetBackgroundTrigger(triggerEventKinds);
builder.SetTrigger(trigger);
await BackgroundExecutionManager.RequestAccessAsync();
BackgroundTaskRegistration task = builder.Register();
task.Completed += new BackgroundTaskCompletedEventHandler(OnCompleted);
}
else
{
foreach (var task in BackgroundTaskRegistration.AllTasks)
{
if (task.Value.Name == TaskName)
{
task.Value.Unregister(true);
break;
}
}
}
}
}
}
private void StartWatcher()
{
DeviceWatcherEventKind[] triggerEventKinds = { DeviceWatcherEventKind.Add, DeviceWatcherEventKind.Remove, DeviceWatcherEventKind.Update };
DeviceWatcher deviceWatcher = null;
startWatcherButton.IsEnabled = false;
// First get the device selector chosen by the UI.
DeviceSelectorInfo deviceSelectorInfo = (DeviceSelectorInfo)selectorComboBox.SelectedItem;
if (null == deviceSelectorInfo.Selector)
{
// If the a pre-canned device class selector was chosen, call the DeviceClass overload
deviceWatcher = DeviceInformation.CreateWatcher(deviceSelectorInfo.DeviceClassSelector);
}
else if (deviceSelectorInfo.Kind == DeviceInformationKind.Unknown)
{
// Use AQS string selector from dynamic call to a device api's GetDeviceSelector call
// Kind will be determined by the selector
deviceWatcher = DeviceInformation.CreateWatcher(
deviceSelectorInfo.Selector,
null // don't request additional properties for this sample
);
}
else
{
// Kind is specified in the selector info
deviceWatcher = DeviceInformation.CreateWatcher(
deviceSelectorInfo.Selector,
null, // don't request additional properties for this sample
deviceSelectorInfo.Kind);
}
// Get the background trigger for this watcher
DeviceWatcherTrigger deviceWatcherTrigger = deviceWatcher.GetBackgroundTrigger(triggerEventKinds);
rootPage.NotifyUser("Starting Watcher...", NotifyType.StatusMessage);
// Register this trigger for our background task
RegisterBackgroundTask(deviceWatcherTrigger);
stopWatcherButton.IsEnabled = true;
rootPage.NotifyUser("Watcher started...", NotifyType.StatusMessage);
}