public MessagePage(Theme theme) { timer.Tick += Timer_Tick; timer.Interval = new TimeSpan(0, 0, 3); timer.Start(); InitializeComponent(); timer.Interval = new TimeSpan(0, 0, 3); timer.Tick += Timer_Tick; timer.Start(); string accName = ""; foreach (var item in messageService.GetMessages()) { foreach (var user in accService.GetAccounts()) { if (item.UserId == user.Id) { accName = user.FirstName + " " + user.LastName; } } if (item.ThemeId == theme.Id) { lv_Chat.Items.Add(new ListViewMessageModel { Name = accName, UserRole = item.UserId.ToString(), Content = item.Content.ToString() }); } } Theme = theme; }