public UserAvatarViewModel() { DiskQuota = new ClientServer(ClientServer.AuthenticationMounted).GetQuotaInfo(); _used = DiskQuota.used / 1024 / 1024 / 1024; _total = DiskQuota.total / 1024 / 1024 / 1024; ChangeWallPaperCmd = new DelegateCommand(() => InitialWallPaper()); InitialWallPaper(); SignOutCmd = new DelegateCommand(() => { var signout = new ClientServer(ClientServer.AuthenticationMounted); if (signout.Logout()) { Application.Current.Shutdown(); } }); }