public override void ViewDidLoad()
{
base.ViewDidLoad();
this.Title = "Downloads";
// Add a bar button item to exit the app manually. Don't do this in productive apps - Apple won't approve it!
// We have it here to demonstrate that iOS will relaunch the app if a download has finished.
this.NavigationItem.LeftBarButtonItem = new UIBarButtonItem("Quit", UIBarButtonItemStyle.Plain, delegate {
// Store all download info to disk. If iOS terminates the app, this would be handled in WillTerminate().
// However this won't be triggered if the app is killed manually by this call.
AppDelegate.SerializeAvailableDownloads();
// Exit application with code 3.
FileTransferController.Exit(3);
});
// Add a bar button item to reset all downloads.
var refreshBtn = new UIBarButtonItem(UIBarButtonSystemItem.Refresh);
refreshBtn.Clicked += async(sender, e) => {
var pendingTasks = await this.Session.GetTasksAsync();
if (pendingTasks != null && pendingTasks.DownloadTasks != null)
{
foreach (var task in pendingTasks.DownloadTasks)
{
task.Cancel();
}
}
AppDelegate.AvailableDownloads.ForEach(info => {
if (info.DestinationFile != null)
{
try
{
File.Delete(info.DestinationFile.Path);
}
catch (Exception ex)
{
Console.WriteLine("Failed to delete '{0}': {1}", info.DestinationFile, ex);
}
}
info.Reset();
info.Status = DownloadInfo.STATUS.Idle;
});
AppDelegate.ResetAvailableDownloads();
((DelegateTableViewSource <DownloadInfo>)(this.TableView.Source)).Items = AppDelegate.AvailableDownloads;
this.TableView.ReloadData();
AppDelegate.SerializeAvailableDownloads();
};
this.NavigationItem.RightBarButtonItem = refreshBtn;
// TODO: FileTransfer 01 - Create a session
// Initialize our session config. We use a background session to enabled out of process uploads/downloads. Note that there are other configurations available:
// - DefaultSessionConfiguration: behaves like NSUrlConnection. Used if *background* transfer is not required.
// - EphemeralSessionConfiguration: use if you want to achieve something like private browsing where all sesion info (e.g. cookies) is kept in memory only.
using (var sessionConfig = UIDevice.CurrentDevice.CheckSystemVersion(8, 0) ? NSUrlSessionConfiguration.CreateBackgroundSessionConfiguration(SessionId) : NSUrlSessionConfiguration.BackgroundSessionConfiguration(SessionId))
{
// Allow downloads over cellular network too.
sessionConfig.AllowsCellularAccess = true;
// We want our app to be launched if required.
sessionConfig.SessionSendsLaunchEvents = true;
// Give the OS a hint about what we are downloading. This helps iOS to prioritize. For example "Background" is used to download data that was not requested by the user and
// should be ready if the app gets activated.
sessionConfig.NetworkServiceType = NSUrlRequestNetworkServiceType.Default;
// Configure how many downloads we allow at the same time. Set to 2 to see that further downloads start once the first two have been completed.
sessionConfig.HttpMaximumConnectionsPerHost = 2;
// TODO: FileTransfer 02 - Create a session delegate and the session itself
// Initialize the session itself with the configuration and a session delegate.
var sessionDelegate = new SessionDelegate(this);
this.Session = NSUrlSession.FromConfiguration(sessionConfig, sessionDelegate, null);
}
// Create a source for the table view.
var source = new DelegateTableViewSource <DownloadInfo> (this.TableView, "downloaderCellId")
{
Items = AppDelegate.AvailableDownloads,
GetCellFunc = (info, cell) =>
{
var downloaderCell = (DownloaderCell)cell;
downloaderCell.UpdateFromDownloadInfo(info);
return(downloaderCell);
},
RowSelectedFunc = info =>
{
if (info.Status == DownloadInfo.STATUS.Completed)
{
var previewController = UIDocumentInteractionController.FromUrl(info.DestinationFile);
previewController.Delegate = new PreviewDelegate(this);
previewController.PresentPreview(true);
}
}
};
this.TableView.RowHeight = 55;
this.TableView.Source = source;
// Trigger a delegate if the user taps a button of a cell.
DownloaderCell.ActionRequested = this.HandleActionRequested;
}