| ❗ There is also a version of this document with code samples in VB.Net ❗ |
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The NavigationService is in charge of handling the navigation between app pages.
NavigationService is defined as a static class that uses the Navigate method to navigate between pages and uses the target page type as a parameter.
App.xaml.cs creates the ActivationService and passes it the current App instance, the default navigation target, and, optionally, a UIElement to act as a navigation shell. If no shell is specified the current window content will be initialized as a Frame.
Normal launching of the app is passed by the ActivationService to the DefaultLaunchActivationHandler and this also sets the default page to display when launching the app.
Navigation differs between different project types.
- Blank project type sets Window.Current.Content as a new Frame and navigates to the HomePage by default. NavigationService will do future navigation in this frame.
- Navigation Pane project type sets Window.Current.Content as a new ShellPage instance. This ShellPage will set NavigationService frame to a frame within the page and NavigationService will do future navigation in this frame. You can find more on configuring code generated with this project type here.
- Pivot and Tabs project type sets Window.Current.Content as a new Frame and navigates to PivotPage that contains a PivotControl, this PivotControl contains one PivotItem for each page. PivotItems contains header text and a Frame set display the configured page. With this project type, the NavigationService does not manage navigating between pivot items, but could be used to navigate away from the PivotPage if necessary.
This sample is based on Windows Template Studio 1.3 release and shows an app which includes a startup page that is displayed before navigating to a shell page and then behaving like a Navigation Pane project. The following code uses Code Behind, versions for MVVM Light and MVVM Basic are also available.
- Step 1. Navigate to the Start Page
In App.xaml.cs the ActivationService has been changed to start on the new page.
private ActivationService CreateActivationService()
{
//This is the default navigation for a NavigationPane project type
//return new ActivationService(this, typeof(Views.HomePage), new Views.ShellPage());
//We are going to initialize navigation to a StartPage
return new ActivationService(this, typeof(Views.StartPage));
}- Step 2. Return to normal Navigation Pane navigation.
Navigate to the ShellPage and this will reset the NavigationService Frame to it's own custom Frame.
Then navigate to HomePage so something is displayed in the shell.
All subsequent navigation just requires a single Navigate() call.
From StartPage.xaml.cs
private void StartButton_Click(object sender, Windows.UI.Xaml.RoutedEventArgs e)
{
//Navigating to a ShellPage, this will replaces NavigationService frame for an inner frame to change navigation handling.
NavigationService.Navigate<Views.ShellPage>();
//Navigating now to a HomePage, this will be the first navigation on a NavigationPane menu
NavigationService.Navigate<Views.HomePage>();
}The three pages in this sample and the order in which they can be navigated to are shown below.
Additional navigation scenarios are covered here.