public USBControl()
{
InitializeComponent();
ThisPage = this;
InitializeTreeView();
Nav.Navigate(typeof(USBFilePresenter), Nav, new DrillInNavigationTransitionInfo());
FolderTracker = new FileSystemTracker(FolderTree.RootNodes.FirstOrDefault());
FolderTracker.Created += FolderTracker_Created;
FolderTracker.Deleted += FolderTracker_Deleted;
FolderTracker.Renamed += FolderTracker_Renamed;
Application.Current.Suspending += Current_Suspending;
Loaded += USBControl_Loaded;
}
private void Current_Suspending(object sender, Windows.ApplicationModel.SuspendingEventArgs e)
{
if (FileTracker != null)
{
FileTracker.Created -= FileTracker_Created;
FileTracker.Deleted -= FileTracker_Deleted;
FileTracker.Renamed -= FileTracker_Renamed;
FileTracker.Dispose();
FileTracker = null;
}
if (FolderTracker != null)
{
FolderTracker.Created -= FolderTracker_Created;
FolderTracker.Deleted -= FolderTracker_Deleted;
FolderTracker.Renamed -= FolderTracker_Renamed;
FolderTracker.Dispose();
FolderTracker = null;
}
}
public FolderService()
{
this.Files = new ConcurrentDictionary<string, FileData>(StringComparer.InvariantCultureIgnoreCase);
this.Tree = new SortedObservableCollection<FileData>(FileData.Comparer);
this._tracker = new FileSystemTracker(this.Tree, this._files);
}
public FolderService()
{
this.Files = new ConcurrentDictionary <string, FileData>(StringComparer.InvariantCultureIgnoreCase);
this.Tree = new SortedObservableCollection <FileData>(FileData.Comparer);
this._tracker = new FileSystemTracker(this.Tree, this._files);
}
private async void FileTree_ItemInvoked(TreeView sender, TreeViewItemInvokedEventArgs args)
{
/*
* 同一文件夹内可能存在大量文件
* 因此切换不同文件夹时极有可能遍历文件夹仍未完成
* 此处激活取消指令，等待当前遍历结束，再开始下一次文件遍历
* 确保不会出现异常
*/
//防止多次点击同一文件夹导致的多重查找
if ((args.InvokedItem as TreeViewNode).Content is StorageFolder folder)
{
if (folder.FolderRelativeId == CurrentFolder?.FolderRelativeId)
{
IsAdding = false;
return;
}
if (IsAdding)
{
await Task.Run(() =>
{
lock (SyncRootProvider.SyncRoot)
{
CancelToken.Cancel();
Locker.WaitOne();
}
});
}
IsAdding = true;
CurrentFolder = folder;
CurrentNode = args.InvokedItem as TreeViewNode;
USBFilePresenter.ThisPage.DisplayNode = CurrentNode;
//当处于USB其他附加功能的页面时，若点击文件目录则自动执行返回导航
if (Nav.CurrentSourcePageType.Name != "USBFilePresenter")
{
Nav.GoBack();
}
USBFilePresenter.ThisPage.FileCollection.Clear();
QueryOptions Options = new QueryOptions(CommonFileQuery.DefaultQuery, null)
{
FolderDepth = FolderDepth.Shallow,
IndexerOption = IndexerOption.UseIndexerWhenAvailable
};
Options.SetThumbnailPrefetch(ThumbnailMode.ListView, 60, ThumbnailOptions.ResizeThumbnail);
var FileQuery = folder.CreateFileQueryWithOptions(Options);
var FileList = await FileQuery.GetFilesAsync();
USBFilePresenter.ThisPage.HasFile.Visibility = FileList.Count == 0 ? Visibility.Visible : Visibility.Collapsed;
if (FileTracker != null)
{
FileTracker.Created -= FileTracker_Created;
FileTracker.Deleted -= FileTracker_Deleted;
FileTracker.Renamed -= FileTracker_Renamed;
FileTracker.Dispose();
FileTracker = null;
}
FileTracker = new FileSystemTracker(FileQuery);
FileTracker.Created += FileTracker_Created;
FileTracker.Deleted += FileTracker_Deleted;
FileTracker.Renamed += FileTracker_Renamed;
foreach (var file in FileList)
{
if (CancelToken.IsCancellationRequested)
{
goto FLAG;
}
USBFilePresenter.ThisPage.FileCollection.Add(new RemovableDeviceFile(file));
}
}
FLAG:
if (CancelToken.IsCancellationRequested)
{
CancelToken.Dispose();
CancelToken = new CancellationTokenSource();
Locker.Set();
}
else
{
IsAdding = false;
}
}
