public BackgroundTransferControl()
{
InitializeComponent();
_request = BackgroundTransferService.Requests.FirstOrDefault(s => s.Tag == "Channel9Download");
if (_request != null)
{
_monitor = new TransferMonitor(_request);
_monitor.Failed += TransferFailed;
Control1.DataContext = _monitor;
}
}
private void BeginDownload()
{
using (var storage = IsolatedStorageFile.GetUserStoreForApplication())
{
if (storage.FileExists("/shared/transfers/channel9.mp3"))
storage.DeleteFile("/shared/transfers/channel9.mp3");
}
_request = new BackgroundTransferRequest(
new Uri("http://media.ch9.ms/ch9/7e13/ce6ea97c-e233-4e7c-a74d-ee1c81e37e13/WP8JumpStart04.mp3",
UriKind.Absolute),
new Uri("/shared/transfers/channel9.mp3", UriKind.Relative)) { Tag = "Channel9Download", TransferPreferences = TransferPreferences.AllowBattery };
_monitor = new TransferMonitor(_request);
Control1.DataContext = _monitor;
_monitor.RequestStart(); //This adds request to the BackgroundTransferService queue.
}
private void RestartDownload()
{
try
{
BackgroundTransferService.Remove(_request);
}
catch (Exception)
{
//No need to worry. These errors can be surpressed. We are just making sure the download has been completed cancelled.
}
_request = null;
_monitor = null;
BeginDownload();
}
public BackgroundTransferQueue()
{
InitializeComponent();
// Load existing background requests into the collection
foreach (BackgroundTransferRequest request in BackgroundTransferService.Requests)
{
var monitor = new TransferMonitor(request);
SubscribeMonitor(monitor);
_list.Add(monitor);
}
TransfersList.DataContext = _list;
// Subscribe buttons to actions
_selectButton.Click += OnSelectButtonClick;
_addButton.Click += OnAddButtonClick;
_cancelButton.Click += OnCancelButtonClick;
_list.CollectionChanged += delegate { _selectButton.IsEnabled = (_list.Count > 0); };
ReloadApplicationBar();
}
private TransferMonitorViewModel(TransferMonitor monitor)
{
Monitor = monitor;
}
private void UnsubscribeMonitor(TransferMonitor monitor)
{
monitor.Failed -= TransferCanceled;
}
public void SubscribeMonitor(TransferMonitor monitor)
{
UnsubscribeMonitor(monitor); // prevent duplicate subscription
monitor.Failed += TransferCanceled;
}
/// <summary>
/// This function is for demo purposes. It adds three files to the background download queue and displays them in the multi-select list.
/// </summary>
private void OnAddButtonClick(object sender, EventArgs e)
{
Dictionary<string, Uri> urlPresets = new Dictionary<string, Uri>
{
{"21 MB File",new Uri("http://media.ch9.ms/ch9/ecbc/cfcb0ad7-fbdd-47b0-aabf-4da5e3e0ecbc/WP8JumpStart06.mp3",UriKind.Absolute)},
{"34 MB File",new Uri("http://media.ch9.ms/ch9/7e13/ce6ea97c-e233-4e7c-a74d-ee1c81e37e13/WP8JumpStart04.mp3",UriKind.Absolute)},
{"92 MB File",new Uri("http://media.ch9.ms/ch9/7e13/ce6ea97c-e233-4e7c-a74d-ee1c81e37e13/WP8JumpStart04.wmv",UriKind.Absolute)},
};
foreach (var preset in urlPresets)
{
Uri saveLocation = new Uri("/shared/transfers/" + preset.Key, UriKind.Relative);
BackgroundTransferRequest request = new BackgroundTransferRequest(preset.Value, saveLocation)
{
TransferPreferences = TransferPreferences.AllowBattery // Note: this will not use cellular data to download
};
TransferMonitor monitor = new TransferMonitor(request, preset.Key);
try
{
BackgroundTransferService.Add(request);
}
catch (Exception err) // An exception is thrown if this transfer is already requested.
{
Debug.WriteLine(err);
continue;
}
monitor.Failed += TransferCanceled;
_list.Add(monitor);
}
}
