wp7 guideline for android developer中一个小问题
protected override void OnBackKeyPress(System.ComponentModel.CancelEventArgs e) { base.OnBackKeyPress(e); Utils.trace("Back key press"); txtItem.Text = ""; Utils.saveShoppingList((App.Current.RootVisual as PhoneApplicationFrame).DataContext as ShoppingListInfo, "ShoppingListInfo.dat"); }下面是ShoppingListInfo类的定义:public class ShoppingListInfo { public ShoppingListInfo(string item, string list) { this.txtItem = item; this.txtList = list; } public ShoppingListInfo() { } public string txtItem; public string txtList; }请问下,为什么我该如何定义ShoppingListInfo,才能保存界面信息呢