c# - 扩展 ContentView 时获取 "The name ' SomeName' does not exist in the current context"

Question

首先，我有一个名为 ComponentView 的抽象类继承自 ContentView:

public abstract class ComponentView : ContentView
{
    private ComponentView() {}

    protected ComponentView(Component component)
    {

    }
}

上面的类由一些自定义的可视化组件扩展。我首先创建了一个名为 SeparatorView 的组件。 XAML结构和C Sharp代码隐藏代码如下:

代码隐藏:

[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class SeparatorView : ComponentView
{
    private readonly Separator _separator;

    public SeparatorView(Separator separator) : base(separator)
    {
        _separator = separator ?? throw new ArgumentException("Separator cannot be null");

        InitializeComponent();
        RootComponent.AutomationId = _separator.Id;
        Label.Text = _separator.Label;
        HelpBlock.Text = _separator.HelpBlock;
    }
}

XAML 文件:

<?xml version="1.0" encoding="utf-8" ?>
<d:ComponentView x:Name="RootComponent" xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:d="clr-namespace:CustomViews.Components"
             x:Class="CustomViews.Components.SeparatorView">
        <StackLayout>
            <Label x:Name="Label"
                VerticalOptions="CenterAndExpand" 
                HorizontalOptions="CenterAndExpand" />
            <Label x:Name="HelpBlock"
                   VerticalOptions="CenterAndExpand" 
                   HorizontalOptions="CenterAndExpand" />
        </StackLayout>
</d:ComponentView>

当我尝试使用此自定义 SeparatorView 时，我在编译时遇到此错误:

var separator = new Separator
{
    Id = "id",
    Label = "Separator",
    HelpBlock = "Help block"
};
var separatorView = new SeparatorView(separator);
StackLayout.Children.Add(separatorView);

SeparatorView.xaml.cs(17, 13): [CS0103] The name 'RootComponent' does not exist in the current context

当我删除该行时:

RootComponent.AutomationId = _separator.Id;

代码有效，我的组件已正确呈现。

我是不是忘记了什么？这与我的类(class)结构有关吗？

Answer 1

您不能命名根元素。事实上，没有必要，因为该元素是您已经在其中的类，它实际上是 this。所以不是:

RootComponent.AutomationId = _separator.Id;

只需这样做:

this.AutomationId = _separator.Id;?