Xamarin DataTemplate与代码背后的绑定不起作用

我试图在我的应用程序中创建一个页面，该页面中的所有控件都是通过后面的C#代码动态生成的.我正在使用Nuget包DLToolkit, flowlist创建流列表.

I have tried to make a page in my app where all controls are generated dynamically via C# code behind. I am using a Nuget Packages, DLToolkit, flowlist to create a flow list.

在使用 Xaml 之前，我已经在我的项目中使用了此软件包，该软件包可以正常使用. 但是，当我尝试在后面的代码中创建datatemplate时，它仅显示一个空白控件，但是将鼠标悬停在该控件上方时，您会看到其中确实有项目.

I have already used this package in my project before using Xaml, and it fully works. However when I try to create a datatemplate in code behind, it just displays a blank control, however when hovering above this control, you can see there's actually items in it.

我的问题是:我该如何在后面的代码中创建带有数据绑定的数据模板?

这是一个示例，可以在 Xaml 中使用:

Here is an example and works in Xaml:

<flv:FlowListView x:Name="flvList" BackgroundColor="White" FlowColumnCount="3" FlowItemsSource="{Binding LstItemSource}" HasUnevenRows="True">
            <flv:FlowListView.FlowColumnTemplate>
                <DataTemplate>

                    <StackLayout BackgroundColor="White" Padding="2" HorizontalOptions="FillAndExpand">

                        <Frame  Margin="20" Padding="0" HeightRequest="175" OutlineColor="Gray" BackgroundColor="White" CornerRadius="10" HasShadow="True" IsClippedToBounds="True">
                            <Frame.Content>

                                <AbsoluteLayout HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand" >
                                    <Image Aspect="AspectFill" AbsoluteLayout.LayoutBounds="1,1,1,1" AbsoluteLayout.LayoutFlags="All"  Source="{Binding BgImage}" />
                                    <BoxView Color="Black" Opacity=".5"  AbsoluteLayout.LayoutBounds="1,1,1,1" AbsoluteLayout.LayoutFlags="All"/>
                                    <StackLayout Margin="20" VerticalOptions="CenterAndExpand" HorizontalOptions="CenterAndExpand">
                                        <Label Text="{Binding SubTitle}"  FontSize="Medium" TextColor="#66FFFFFF"/>
                                        <Label Text="{ Binding Title}" FontSize="Large" TextColor="White" />
                                    </StackLayout>
                                </AbsoluteLayout>

                            </Frame.Content>
                        </Frame>

                    </StackLayout>

                </DataTemplate>
            </flv:FlowListView.FlowColumnTemplate>
        </flv:FlowListView>

但是，在此项目中生成了控件，因此没有涉及 Xaml 的代码. 这是我在后面的代码中尝试过的代码示例，但是不起作用:

However, in this project the controls are generated, so there is no Xaml code involved. This is an example of the code that I've tried in code behind, but doesn't work:

#region Datatemplate
            var dataTemplate = new DataTemplate(() =>
            {
                var StackLayout = new StackLayout { BackgroundColor = Color.Pink, Padding = 2, HorizontalOptions = LayoutOptions.FillAndExpand };

                #region children/content for frame
                AbsoluteLayout absoluteLayout = new AbsoluteLayout { HorizontalOptions = LayoutOptions.FillAndExpand, VerticalOptions = LayoutOptions.FillAndExpand };


                #region content for AbsoluteLayout
                var imgBg = new Image();
                AbsoluteLayout.SetLayoutBounds(imgBg , new Rectangle(1, 1, 1, 1));
                AbsoluteLayout.SetLayoutFlags(imgBg , AbsoluteLayoutFlags.All);

                imgBg .SetBinding(Image.SourceProperty, "BgImage");
                absoluteLayout.Children.Add(imgBg );


                var overlayBox = new BoxView { Color = Color.Black, Opacity = 0.5 };
                AbsoluteLayout.SetLayoutBounds(overlayBox, new Rectangle(1, 1, 1, 1));
                AbsoluteLayout.SetLayoutFlags(overlayBox, AbsoluteLayoutFlags.All);
                absoluteLayout.Children.Add(overlayBox);


                #region InnerStackpanel
                StackLayout innerStackVoorAbsoluteLayout = new StackLayout { Margin = new Thickness(20), VerticalOptions = LayoutOptions.CenterAndExpand, HorizontalOptions = LayoutOptions.CenterAndExpand };

                var lblTitel = new Label { FontSize = Device.GetNamedSize(NamedSize.Medium, typeof(Label)), TextColor = Color.White };
                var lblSubTitel = new Label { FontSize = Device.GetNamedSize(NamedSize.Medium, typeof(Label)), TextColor = Color.White };


                //Bindings 
                lblTitel.SetBinding(Label.TextProperty, "Title");
                lblSubTitel.SetBinding(Label.TextProperty, "SubTitle");

                innerStackVoorAbsoluteLayout.Children.Add(lblSubTitel);
                innerStackVoorAbsoluteLayout.Children.Add(lblTitel);

                absoluteLayout.Children.Add(innerStackVoorAbsoluteLayout);
                #endregion

                #endregion


                #endregion

                Frame frame = new Frame();
                frame.Content = absoluteLayout;



                StackLayout.Children.Add(frame);


                return StackLayout;
            });

            #endregion


            FlowListView lstRelatieLijst = new FlowListView();
            lstRelatieLijst.ItemsSource = lstRelatieItems;
            lstRelatieLijst.FlowColumnTemplate = dataTemplate;
            lstRelatieLijst.BackgroundColor = Color.LightGoldenrodYellow;
            lstRelatieLijst.FlowColumnCount = 1;
            lstRelatieLijst.HasUnevenRows = true;


            #endregion

请问有人可以给我一些建议，让我像后面的代码中的上层 Xaml 一样吗?

Can someone give me some advice how I can become something similar like the upper Xaml in code behind, please?

我已经尝试了以下来源，但不幸的是，我没有按预期工作.我希望看到相同的结果或类似的XAML代码.但是在关注他们的信息之后，FLowListView似乎为空:

I already tried the following sources but unfortunately I doesn't work as expected. I hoped to see the same result or something similar like the XAML code. But after following their info,the FLowListView appears to be empty:

https://docs.microsoft.com/en-us/xamarin/xamarin-forms/app-fundamentals/templates/data-templates/creating

https://www.codeproject.com/Questions/516614/createplusdatatemplatepluscodeplusbehind