Question

我正在使用模板10创建UWP应用程序。我已经创建了这样的用户控件。

 <my:DeviceInfoUserControl  OnEndpointTypeChange="{Binding OnEndpointTypeChangeCommand}" Component="{Binding DeviceManagementViewModel,Mode=TwoWay}"></my:DeviceInfoUserControl>

我在用户控制上有单选按钮。我在多个屏幕上添加了用户控件。

此用户控件具有自己的ViewModel以及一些依赖项属性，如下所示：

public class DeviceManagementViewModel : ViewModelBase
{

}
public sealed partial class DeviceInfoUserControl : UserControl
{
    public bool IsToggled = true;
    public DeviceInfoUserControl()
    {
        this.InitializeComponent();
    }

    public static readonly DependencyProperty OnEndpointTypeChangeProperty =
      DependencyProperty.Register(
          "OnEndpointTypeChange",
          typeof(ICommand),
          typeof(DeviceInfoUserControl), new PropertyMetadata(null));

    public ICommand OnEndpointTypeChange
    {
        get { return (ICommand)GetValue(OnEndpointTypeChangeProperty); }
        set { SetValue(OnEndpointTypeChangeProperty, value); }
    }

    public static readonly DependencyProperty ComponentProperty = DependencyProperty.Register("Component", typeof(DeviceManagementViewModel), typeof(DeviceInfoUserControl), new PropertyMetadata(null));

    public DeviceManagementViewModel Component
    {
        get { return (DeviceManagementViewModel)GetValue(ComponentProperty); }
        set { SetValue(ComponentProperty, value); }
    }
}

我希望在所有屏幕上保留单选按钮选择。我该怎么做到这一点？

Answer 1

您必须确保将相同的ViewModel实例用于所有控件实例。 XAML方式总是创建新实例：

<Page.DataContext>
    <vm:DetailPageViewModel x:Name="ViewModel" />
</Page.DataContext>

在使用Bootstrapper方法覆盖的Template10的ResolveForPage类中，您可以在页面导航后通过自定义逻辑或依赖注入注入ViewModel LINK

Answer 2

不知道它的改进方式与否，但我通过制作Singletone Viewmodel实现了这一目标。

 public class DeviceManagementViewModel : ViewModelBase
 {
    public static readonly DeviceManagementViewModel _instance = new DeviceManagementViewModel ();
    private DeviceManagementViewModel ()
    {

    }
/*Properties and Methods */

}

在父屏幕ViewModel中，我创建了以下属性

 private DeviceManagementViewModel  _deviceManagementViewModel;
        public DeviceManagementViewModel DeviceManagementViewModel1
        {
                    get { return _deviceManagementViewModel; }
                    set { Set(ref _deviceManagementViewModel, value); }
        }

我在Constructor中有Instantiated属性：

  public ConfigurationViewModel()
  {
    DeviceManagementViewModel1 = DeviceManagementViewModel._instance;
  }

用户控制：

<my:DeviceInfoUserControl  OnEndpointTypeChange="{Binding OnEndpointTypeChangeCommand}"  Component="{Binding DeviceManagementViewModel1,Mode=TwoWay}"></my:DeviceInfoUserControl>

使用模板10维护UWP应用程序中的用户控制状态

2 个答案: