如何更改TabbedPage中的默认选中项？

<TabbedPage xmlns="http://xamarin.com/schemas/2014/forms"
            xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
            x:Class="YourNamespace.MainPage">
    <TabbedPage.Children>
        <ContentPage Title="Page 1">
            <!-- Content of Page 1 -->
        </ContentPage>
        <ContentPage Title="Page 2">
            <!-- Content of Page 2 -->
        </ContentPage>
        <ContentPage Title="Page 3">
            <!-- Content of Page 3 -->
        </ContentPage>
    </TabbedPage.Children>
</TabbedPage>

public MainPage()
{
    InitializeComponent();
    CurrentPage = Children[1]; // 设置默认选中第二个页面
}