async Task init()
{
booksource = new BookDataSource();
lo_list = new IGroupList();
lo_list.StackListScrollCompleted += lo_list_StackListScrollCompleted;
lo_list.StackItemFullAnimationCompleted += lo_list_StackItemFullAnimationCompleted;
lo_list.StackItemFullAnimationStarted += lo_list_StackItemFullAnimationStarted;
lo_list.StackItemThumbAnimationStarted += lo_list_StackItemThumbAnimationStarted;
lo_list.StackItemThumbAnimationCompleted += lo_list_StackItemThumbAnimationCompleted;
MainGrid.Children.Add(lo_list);
down_menu = new ControlDownMenu();
MainGrid.Children.Add(down_menu);
down_menu.ControlDownElementSelected += menu_ControlDownElementSelected;
//init data
var vm = ViewModel as LOViewModel;
await vm.InitLoad();
loadLOsInCircle(0);
lo_list.Source = booksource;
down_menu.Source = booksource;
//vm = this.ViewModel as LOViewModel;
vm.PropertyChanged += vm_PropertyChanged;
}