如何获取上下文菜单单击发生位置的父对象属性

Question

我正在尝试根据上下文菜单的单击事件为我的应用程序创建辅助活动磁贴，并且我需要公开 ContextMenu 父对象的一些属性，但我不确定如何执行此操作。基本上，我的 MainPage 上有两个 HubTiles，每个都使用相同的 ContextMenu 点击事件。在 ContextMenu 点击事件MenuItem_Tap 中，我调用了一个方法CreateLiveTile，它应该获取HubTile 的属性，其中发生了上下文菜单点击，以便在将固定到开始屏幕的辅助磁贴中使用。我所拥有的如下，但我不知道如何公开发生 ContextMenu 点击的 HubTile 的属性

MainPage.xaml

 <ListBox Grid.Row="0" x:Name="tileList" toolkit:TiltEffect.IsTiltEnabled="True">
                <ListBox.ItemsPanel>
                    <ItemsPanelTemplate>
                        <toolkit:WrapPanel Orientation="Horizontal" />
                    </ItemsPanelTemplate>
                </ListBox.ItemsPanel>
                <ListBox.ItemTemplate>
                    <DataTemplate>
                        <toolkit:HubTile Title="{Binding Title}" Margin="3"
                                         Notification="{Binding Notification}"
                                         DisplayNotification="{Binding DisplayNotification}"
                                         Message="{Binding Message}"
                                         GroupTag="{Binding GroupTag}"
                                         Source="{Binding ImageUri}"
                                         Tap="hubTile_Tap">
                            <toolkit:ContextMenuService.ContextMenu>
                                <toolkit:ContextMenu x:Name="menu">
                                    <toolkit:MenuItem Header="pin to start" Tap="MenuItem_Tap"/>
                                </toolkit:ContextMenu>
                            </toolkit:ContextMenuService.ContextMenu>
                        </toolkit:HubTile>

                    </DataTemplate>
                </ListBox.ItemTemplate>
            </ListBox>

MainPage.xaml.cs

public MainPage()
    {
        InitializeComponent();

        CreateHubTiles();
    }

private void CreateHubTiles()
    {
        List<TileItem> tileItems = new List<TileItem>() 
        {
            new TileItem() { ImageUri = "/Images/shareStatusImage.jpg", Title = "status", /*Notification = "last shared link uri",*/ Message = Settings.statusMessage.Value, GroupTag = "TileGroup" },
            new TileItem() { ImageUri = "/Images/shareLinkImage.jpg", Title = "link", /*Notification = "last shared status message",*/ Message = "last shared link uri", GroupTag = "TileGroup" }, 
        };

        this.tileList.ItemsSource = tileItems;
    }

private void MenuItem_Tap(object sender, System.Windows.Input.GestureEventArgs e)
    {
        //How to expose which HubTile was selected and its properties?
        //HubTile tap = sender as HubTile;  //not working, sent from ContextMenu not HubTile

        //(sender as MenuItem).
        //(sender as UIElement).
        //string parent = VisualTreeHelper.GetParent((sender as DependencyObject)).ToString();

        //attempt to pass the selected HubTile instance to CreateLiveTiles method
        CreateLiveTile(tap);
    }

    private void CreateLiveTile(HubTile hubtile)
    {
        string _title = hubtile.Title.ToString();

        //var Tile = ShellTile.ActiveTiles.FirstOrDefault(x => x.NavigationUri.ToString().Contains("DefaultTitle=" + LiveTile.Title));
        var Tile = ShellTile.ActiveTiles.FirstOrDefault(x => x.NavigationUri.ToString().Contains("DefaultTitle=" + _title));

        if (Tile == null)
        {
            try
            {
                var LiveTile = new StandardTileData
                {
                    Title = hubtile.Title,
                    BackgroundImage = ((System.Windows.Media.Imaging.BitmapImage)hubtile.Source).UriSource,
                    //Count = 1,
                    BackTitle = hubtile.Title,
                    //BackBackgroundImage = new Uri("", UriKind.Relative),
                    BackContent = hubtile.Message,
                };

                ShellTile.Create(new Uri("/MainPage.xaml?DefaultTitle=" + LiveTile.Title, UriKind.Relative), LiveTile);
            }
            catch (Exception)
            {
                MessageBox.Show("This tile could not be pinned", "Warning", MessageBoxButton.OK);
            }
        }
        else
        {
            MessageBox.Show("This tile has already been pinned", "Notice", MessageBoxButton.OK);
        }
    }

Answer 1

PlacementTarget 是您要查找的内容，如果发件人是 MenuItem，则其父项将是 ContextMenu，您可以从中获取放置此 contextMenu 的 PlacementTarget。

private void MenuItem_Tap(object sender, System.Windows.Input.GestureEventArgs e)
{
   HubTitle tap = (((sender as MenuItem).Parent as ContextMenu).PlacementTarget
                                                            as HubTitle);

   //attempt to pass the selected HubTile instance to CreateLiveTiles method
   CreateLiveTile(tap);
}