無法在代碼后面訪問 Xamarin.Forms.Shapes 命名空間和 API

Question

我正在嘗試使用 Xamarin.Forms 此處顯示的形狀實驗功能創建動態形狀，盡管它在 xaml 中工作，但我需要使用實驗標志動態創建路徑和形狀。

Xamarin 文檔僅顯示 xaml 示例，並且沒有 API 或在代碼后面使用Shapes和Path的參考。

這是我的 Xaml

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage
    x:Class="SpotlightTest.MainPage"
    xmlns="http://xamarin.com/schemas/2014/forms"
    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
    xmlns:d="http://xamarin.com/schemas/2014/forms/design"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d">
    <AbsoluteLayout>
        <StackLayout
            Margin="0"
            AbsoluteLayout.LayoutBounds="0,0,1,1"
            AbsoluteLayout.LayoutFlags="All"
            BackgroundColor="Orange"
            Spacing="0">
            <!--  Place new controls here  -->
            <Button
                BackgroundColor="Yellow"
                BorderColor="Red"
                BorderWidth="2"
                CornerRadius="50"
                HeightRequest="100"
                HorizontalOptions="Start"
                Text="Explore"
                WidthRequest="100" />
            <Label
                HorizontalOptions="Center"
                Text="Welcome to Xamarin.Forms!"
                VerticalOptions="CenterAndExpand" />


        </StackLayout>
        <Grid
            x:Name="ShadowContainer"
            Padding="0"
            AbsoluteLayout.LayoutBounds="0,0,1,1"
            AbsoluteLayout.LayoutFlags="All"
            BackgroundColor="Transparent">
            <Path
                x:Name="MyPath"
                Fill="#66000000"
                Stroke="Red"
                StrokeThickness="1">
                <Path.Data>
                    <GeometryGroup>
                        <EllipseGeometry
                            Center="55,55"
                            RadiusX="55"
                            RadiusY="55" />
                        <RectangleGeometry Rect="00,00,400,700" />
                    </GeometryGroup>
                </Path.Data>
            </Path>
        </Grid>
    </AbsoluteLayout>
</ContentPage>

I have tried to use Shapes and Path even added Xamarin.Forms.Shapes namespace but i am not able to access the API seems like it is not present in the .dll but it worked fine in xaml page, how can i access it in code在后面？ 我正在使用 Xamarin.Forms 4.8.0.1687

Answer 1

首先，您應該在App.xaml.cs中設置Shapes_Experimental標志

public App()
  {
     Device.SetFlags(new[] { "Shapes_Experimental", "Brush_Experimental" });
     InitializeComponent();
     MainPage = new MainPage();
  }

然后您可以在 xaml.cs 后面的代碼中訪問它：

using Xamarin.Forms.Shapes;

Path path = new Path();
path.Fill = new SolidColorBrush(Color.FromHex("#66000000"));
path.Stroke = Brush.Red;
path.StrokeThickness = 1;
GeometryGroup geometryGroup = new GeometryGroup();
geometryGroup.Children.Add(new EllipseGeometry() { Center = new Point(55, 55), RadiusX = 55, RadiusY = 55 });
geometryGroup.Children.Add(new RectangleGeometry() { Rect = new Rect(00,00,400,700) });
path.Data = geometryGroup;
ShadowContainer.Children.Add(path);