Xamarin.forms 在表单中选择Masterpage ListView项时如何更改DetailPage数据

我已经用Xamarin表单创建了一个母版详细信息页面。我只为母版页的每个项目创建了一个DetailPage。因此，当我单击母版页项目时，应该只更改数据，而不更改DetailPage的布局/内容。请帮帮我

母版页：

{
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class ProductSelctionScreen : MasterDetailPage
{
    public string customer;

    public ProductSelctionScreen(string Customer)
    {

        InitializeComponent();

        customer = Customer;

        DetailPage.Choosedcustomer.Text = customer;

        MasterPage.ListView.ItemSelected += ListView_ItemSelected;
    }

    public void ListView_ItemSelected(object sender, SelectedItemChangedEventArgs e)
    {
        var item = e.SelectedItem as ProductSelctionScreenMenuItem;

        if (item == null)
            return;

        var page = (Page)Activator.CreateInstance(item.TargetType);
        page.Title = item.Title;



        switch (page.Title)
        {
            case "Foods":

                if (DetailPage.productListView.ItemsSource != null)
                {
                    DetailPage.productListView.ItemsSource = null;

                    BindingContext = new ProductItemModel1();

                    DetailPage.productListView.SetBinding(ListView.ItemsSourceProperty, new Binding("ProductList"));

                    DetailPage.productListView.SelectedItem = null;
                }


                break;

            case "Beverages":
                break;

            case "Personal Care":
                break;

            case "Health Supplements":
                break;

            case "Cosmetics":
                break;

            case "Ayurveda Medicines":
                break;
        }

        Detail = new NavigationPage(page);

        IsPresented = false;

        MasterPage.ListView.SelectedItem = null;
    }

}

单击母版页中的项目时，我想更改DetailPage Listview（以下）的ItemSource

详细信息页面Xamlfile：

        <ListView x:Name="ProductListView" ItemsSource="{Binding BeverageList}" HasUnevenRows="True"  SeparatorVisibility="None"     >
            <ListView.ItemTemplate>
                <DataTemplate>


                    <local:Productdata/>

                </DataTemplate>
            </ListView.ItemTemplate>
        </ListView>

请编辑您的问题以包括以下内容-1.母版页的代码2.详细信息页的代码和3.代码在选择ListView项目时所采取的操作。最好为所有项目创建新的内容页。否则，您必须在单个详细信息页面中添加所有内容，并有条件地显示它。