Question

我已将复选框的已检查状态保存在隔离存储中，但每当我取消选中该复选框，然后再次启动应用程序时，它仍然会被检查，但我将其状态保存在backkeypress上

这是来自Constructor

if (IsolatedStorageSettings.ApplicationSettings.Contains("mySavedList"))
            {
                lstshopNew = IsolatedStorageSettings.ApplicationSettings["mySavedList"] as List<Shopping>;

                if (lstshopNew.Count > 0)
                {
                    foreach (var item in lstshopNew)
                    {
                        var t = lstShop.Where(s => s.list.Equals(item.list)).FirstOrDefault();

                        if (t != null)
                        {
                            t.IsCompleted = true;
                        }
                    } 
        private void checkboxSL_Checked(object sender, RoutedEventArgs e)
        { 
            //isChkboxChecked = true;
            //(sender as CheckBox).IsChecked = isChkboxChecked;
            //IsolatedStorageSettings.ApplicationSettings["isChecked"] = (sender as CheckBox).IsChecked;

            var chk = (sender as CheckBox).DataContext as Shopping;

            if (chk == null)
            {
                return;
            }

            chk.IsCompleted = true;

            var lstItem = lstShop.Where(x => x.list.Equals(chk.list)).FirstOrDefault();

            if (lstItem != null)
            {
                lstshopNew.Remove(chk);
            }

            lstshopNew.Add(chk);

        }

        private void checkboxSL_Unchecked(object sender, RoutedEventArgs e)
        {
            //(sender as CheckBox).IsChecked = false;
            //IsolatedStorageSettings.ApplicationSettings["isChecked"] = (sender as CheckBox).IsChecked;

            var chk = (sender as CheckBox).DataContext as Shopping;


            if (chk == null)
            {
                return;
            }

            chk.IsCompleted = false;

            var lstItem = lstShop.Where(x => x.list.Equals(chk.list)).FirstOrDefault();

            if (lstItem != null)
            {
                lstshopNew.Remove(chk);
            }
            lstshopNew.Remove(chk);

        }

        protected override void OnBackKeyPress(System.ComponentModel.CancelEventArgs e)
        {
            base.OnBackKeyPress(e);

            IsolatedStorageSettings.ApplicationSettings["mySavedList"] = lstshopNew;
        }

XAML代码

 <ListBox x:Name="listBox2" SelectionMode="Multiple" Grid.Row="1" >
        <ListBox.ItemTemplate>
            <DataTemplate>
                <StackPanel Orientation="Horizontal" Background="White"  >
                    <CheckBox x:Name="checkboxSL" IsChecked="{Binding IsCompleted, Mode=TwoWay}" Checked="checkboxSL_Checked" Unchecked="checkboxSL_Unchecked" BorderBrush="Black" Foreground="Black" Style="{StaticResource CheckBoxStyle1}"/>
                    <TextBlock Text="{Binding list}" FontSize="30" TextWrapping="Wrap" HorizontalAlignment="Left"  Foreground="Black" Margin="0,15,0,0"/>
                </StackPanel>
            </DataTemplate>
        </ListBox.ItemTemplate>
    </ListBox>

Answer 1

您将Shopping放入隔离存储空间。这是具有唯一内存地址的C＃类的实例。然后，您重新运行该应用程序并检查保存的Shopping对象是否与您刚刚创建的Shopping对象相同。事实并非如此，因为这些新对象是具有新内存地址的新实例。

您要做的是将唯一ID（如数字或唯一关键字）放入Shopping类中。然后比较该ID（不是整个对象）以确定存储中的对象是否与GUI上的对象相同。

Answer 2

我对为我工作的事件做了这些修改 private void checkboxSL_Checked（object sender，RoutedEventArgs e） { var chk =（发送者为CheckBox）.DataContext为Shopping;

        if (chk == null)
        {
            return;
        }

        chk.IsCompleted = true;

        var lstItem = lstShop.Where(x => x.list.Equals(chk.list)).FirstOrDefault();

        //if (lstItem != null)
        //{
        //    lstshopNew.Remove(lstItem);
        //}            

        if (lstshopNew.Count > 0)
        {
            foreach (var item in lstshopNew.ToList())
            {
                if (item.list.Equals(lstItem.list))
                {
                    tItem = item.list;
                }
            }

            if (!lstItem.list.Equals(tItem))
            {
                lstshopNew.Add(chk);
            }
        }
        else
        {
            lstshopNew.Add(chk);
        }
    }

    private void checkboxSL_Unchecked(object sender, RoutedEventArgs e)
    {
        var chk = (sender as CheckBox).DataContext as Shopping;

        if (chk == null)
        {
            return;
        }
        chk.IsCompleted = false;

        var lstItem = lstShop.Where(x => x.list.Equals(chk.list)).FirstOrDefault();

        if (lstItem != null)
        {
            foreach (var item in lstshopNew.ToList())
            {
                if (item.list.Equals(lstItem.list))
                {
                    lstshopNew.Remove(item);
                }
            }
        }
    }

我不能通过使用此代码取消选中checkBox

XAML代码

2 个答案: