使用 XAML 進行分層導航

預設情況下，導航模式就像一堆頁面一樣工作，呼叫前一頁面上的最新頁面。你需要使用 NavigationPage 物件。

推送新頁面

...
public class App : Application 
{
    public App() 
    {
        MainPage = new NavigationPage(new Page1());
    }
}
...

Page1.xaml

...
<ContentPage.Content>
    <StackLayout>
        <Label Text="Page 1" />
        <Button Text="Go to page 2" Clicked="GoToNextPage" />
    </StackLayout>
</ContentPage.Content>
...

Page1.xaml.cs

...
public partial class Page1 : ContentPage
{
    public Page1()
    {
        InitializeComponent();
    }
    
    protected async void GoToNextPage(object sender, EventArgs e)
    {
        await Navigation.PushAsync(new Page2());
    }
}
...

Page2.xaml

...
<ContentPage.Content>
    <StackLayout>
        <Label Text="Page 2" />
        <Button Text="Go to Page 3" Clicked="GoToNextPage" />
    </StackLayout>
</ContentPage.Content>
...

Page2.xaml.cs

...
public partial class Page2 : ContentPage
{
    public Page2()
    {
        InitializeComponent();
    }
    
    protected async void GoToNextPage(object sender, EventArgs e)
    {
        await Navigation.PushAsync(new Page3());
    }
}
...

彈出頁面

通常使用者使用後退按鈕返回頁面，但有時你需要以程式設計方式控制它，因此你需要呼叫方法 NavigationPage.PopAsync() 返回上一頁或 NavigationPage.PopToRootAsync() 以在開始時返回，像……

Page3.xaml

...
<ContentPage.Content>
    <StackLayout>
        <Label Text="Page 3" />
        <Button Text="Go to previous page" Clicked="GoToPreviousPage" />
        <Button Text="Go to beginning" Clicked="GoToStartPage" />
    </StackLayout>
</ContentPage.Content>
...

Page3.xaml.cs

...
public partial class Page3 : ContentPage
{
    public Page3()
    {
        InitializeComponent();
    }
    
    protected async void GoToPreviousPage(object sender, EventArgs e)
    {
        await Navigation.PopAsync();
    }

    protected async void GoToStartPage(object sender, EventArgs e)
    {
        await Navigation.PopToRootAsync();
    }
}
...