/// <summary>
/// Tidy up a device that has just been removed from the collection of connected devices
/// </summary>
/// <param name="dpvm">The device just removed</param>
private void OnDeviceRemoved(DevicePortalViewModel dpvm)
{
dpvm.PropertyChanged -= this.DevicePropertyChanged;
if (dpvm.StopListeningForSystemPerfCommand.CanExecute(this))
{
dpvm.StopListeningForSystemPerfCommand.Execute(this);
}
}
/// <summary>
/// Peform the action for the RemoveDevice command
/// </summary>
/// <param name="obj">The device to be removed from the collection of connected devices</param>
private void ExecuteRemoveDeviceCommand(object obj)
{
DevicePortalViewModel dpvm = obj as DevicePortalViewModel;
if (dpvm != null)
{
this.RemoveDevice(dpvm);
}
}
/// <summary>
/// Event handler to monitor property changes on each of the elements in the collection of connected devices
/// </summary>
/// <param name="sender">Device that originated the event</param>
/// <param name="e">The arguments for the event</param>
private void DevicePropertyChanged(object sender, PropertyChangedEventArgs e)
{
if (e.PropertyName == "Ready")
{
DevicePortalViewModel dpvmSender = sender as DevicePortalViewModel;
if (dpvmSender != null && !dpvmSender.Ready)
{
// A device is no-longer ready, so remove it from the current selection
List <DevicePortalViewModel> updatedSelection = new List <DevicePortalViewModel>();
foreach (DevicePortalViewModel dpvm in this.SelectedDevices)
{
if (dpvm.Ready)
{
updatedSelection.Add(dpvm);
}
}
this.SelectedDevices = updatedSelection;
}
this.OnPropertyChanged("SomeDevicesReady");
this.OnPropertyChanged("AllDevicesReady");
}
if (e.PropertyName == "ConnectionStatus")
{
DevicePortalViewModel dpvmSender = sender as DevicePortalViewModel;
if (dpvmSender.ConnectionStatus == DeviceConnectionStatus.Failed)
{
// Check for authentication failure and warn the user about bad credentials
if (dpvmSender.Portal.ConnectionHttpStatusCode == HttpStatusCode.Unauthorized)
{
MessageBox.Show(
"Connection Unauthorized. Please double check your authentication credentials",
"Unauthorized",
MessageBoxButton.OK,
MessageBoxImage.Exclamation);
this.RemoveDevice(dpvmSender);
}
}
}
if (e.PropertyName == "Address")
{
DevicePortalViewModel dpvmSender = sender as DevicePortalViewModel;
if (this.DeviceIsDuplicate(dpvmSender))
{
MessageBox.Show(
string.Format("You already have a connection for this device address: {0}", dpvmSender.Address),
"Duplicate",
MessageBoxButton.OK,
MessageBoxImage.Exclamation);
this.RemoveDevice(dpvmSender);
}
}
}
/// <summary>
/// Perform additional initialization on a device that has been newly added to the collection of connected devices
/// </summary>
/// <param name="dpvm">The device that has been added</param>
private void OnDeviceAdded(DevicePortalViewModel dpvm)
{
dpvm.PropertyChanged += this.DevicePropertyChanged;
CommandSequence cmdSeq = dpvm.CreateCommandSequence();
cmdSeq.RegisterCommand(dpvm.ReestablishConnectionCommand);
cmdSeq.RegisterCommand(dpvm.RefreshDeviceNameCommand);
cmdSeq.RegisterCommand(dpvm.StartListeningForSystemPerfCommand);
cmdSeq.Execute(null);
}
/// <summary>
/// Predicate for the RemoveDevice command
/// </summary>
/// <param name="arg">The device to be removed from the collection</param>
/// <returns>Result indicates whether the command can execute</returns>
private bool CanExecuteRemoveDeviceCommand(object arg)
{
DevicePortalViewModel dpvm = arg as DevicePortalViewModel;
if (dpvm != null)
{
return(dpvm.Ready);
}
return(false);
}
/// <summary>
/// Determine whether the provided DevicePortalViewModel is already represented in the collection
/// </summary>
/// <param name="dpvmToCheck">The DevicePortalViewModel for which you want to check for duplicates</param>
/// <returns>True if the device is already represented in the collection</returns>
private bool DeviceIsDuplicate(DevicePortalViewModel dpvmToCheck)
{
foreach (DevicePortalViewModel dpvm in this.ConnectedDevices)
{
if (dpvmToCheck == dpvm)
{
continue;
}
if (dpvmToCheck.Address == dpvm.Address)
{
return(true);
}
}
return(false);
}
/// <summary>
/// Removes a device from the collection and clears any pending commands
/// </summary>
/// <param name="removeMe">The device to remove</param>
private void RemoveDevice(DevicePortalViewModel removeMe)
{
removeMe.ClearCommandQueue();
this.ConnectedDevices.Remove(removeMe);
}