public void OpenedDirectory(string curdirfullname)
        {
            navigationView.ClearItems();



            IDirectory curdir;
            ICollection <IDirectory> dirs;
            ICollection <IFile>      files;

            //NavigationView.IListBox.Clear();
            navigationView.IListBox = new List <string>();
            curdir = new MyDirectory(curdirfullname);

            dirs  = curdir.GetDirectories();
            files = curdir.GetFiles();

            navigationView.ICurrentDir = curdir.FullName;

            if (curdir.FullName.Length > 3)
            {
                navigationView.IListBox.Add("..");
            }

            foreach (MyDirectory dir in dirs)
            {
                navigationView.IListBox.Add(dir.Name);
            }
            foreach (MyFile file in files)
            {
                navigationView.IListBox.Add(file.Name);
            }

            navigationView.Improve_Changes();
        }