The FrameNavigationService is an INavigationService implementation that allows you to navigate between Views within a NavigationFrame.
Note
The service also implements the IDocumentManagerService interface. It allows you to interact with a FrameNavigationService instance as with a document manager service. See Document Services to learn more.
Assume that you need to implement a slide navigation between Views in your MVVM application. To accomplish this task, you can use the FrameNavigationService. Add the FrameNavigationService to NavigationFrame’s Interaction.Behaviors.
xmlns:dxwui="http://schemas.devexpress.com/winfx/2008/xaml/windowsui"
xmlns:dxmvvm="http://schemas.devexpress.com/winfx/2008/xaml/mvvm"
...
<dxwui:NavigationFrame>
<dxmvvm:Interaction.Behaviors>
<dxwuin:FrameNavigationService />
</dxmvvm:Interaction.Behaviors>
</dxwui:NavigationFrame>
Access the FrameNavigationService in our View Model defined as a POCO object and navigate to the required View by using the INavigationService.Navigate method. If the View Model is inherited from the ViewModelBase, use the approach from Services in ViewModelBase descendants.
public class MainViewModel {
private INavigationService NavigationService { get { return this.GetService<INavigationService>(); } }
public MainViewModel() { }
public void OnViewLoaded() {
NavigationService.Navigate("HomeView", null, this);
}
}
In the code snippet above, you can see how to navigate to the HomeView.
In addition to the Navigate method, the INavigationService interface also provides the following navigation methods.
- GoBack - performs a navigation to the previous view, if permitted.
- GoForward - performs a navigation to the next view, if permitted.
Views caching support
The NavigationFrame associated with the FrameNavigationService allows you to cache the shown Views. Depending on the NavigationFrame.NavigationCacheMode property value, a NavigationFrame can cache Views to which it navigates in multiple modes: cache always, cache until the cache size exceeds the defined value, or do not cache at all. The NavigationPages provide the attached NavigationPage.NavigationCacheMode property that overrides the NavigationCacheMode method for specific elements.
Processing navigation in ViewModel
To support the navigation processing at ViewModels’ level, you can implement the ISupportNavigation interface in your ViewModels. The ISupportNavigation members that occur when navigating to an object and when navigating away from it.
Splash Screen Showing
If you are navigating between content-heavy Views with complex structure, you can show a splash screen by using the FrameNavigationService.ShowSplashScreen while the NavigationFrame content is loading.
Example
The FrameNavigationService provides methods to navigate between Views within a NavigationFrame. This example shows how to use this service. In this example, the MainWindow contains a NavigationFrame, which shows a HomeView at startup. The HomeView contains a Tile, which invokes a command to navigate to a DetailView when clicked. The DetailView contains the Back button for backward navigation.
<UserControl x:Class="DXSample.View.MainView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:dxwui="http://schemas.devexpress.com/winfx/2008/xaml/windowsui"
xmlns:dxwuin="http://schemas.devexpress.com/winfx/2008/xaml/windowsui/navigation"
xmlns:dxmvvm="http://schemas.devexpress.com/winfx/2008/xaml/mvvm"
xmlns:ViewModel="clr-namespace:DXSample.ViewModel"
mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="300"
DataContext="{dxmvvm:ViewModelSource Type={x:Type ViewModel:MainViewModel}}">
<Grid>
<dxwui:NavigationFrame AnimationType="SlideHorizontal" NavigationCacheMode="Required">
<dxmvvm:Interaction.Triggers>
<dxmvvm:EventToCommand EventName="Loaded" Command="{Binding OnViewLoadedCommand}" />
</dxmvvm:Interaction.Triggers>
<dxmvvm:Interaction.Behaviors>
<dxwuin:FrameNavigationService />
</dxmvvm:Interaction.Behaviors>
</dxwui:NavigationFrame>
</Grid>
</UserControl>
using DevExpress.Mvvm;
using DevExpress.Mvvm.POCO;
namespace DXSample.ViewModel {
public class MainViewModel {
private INavigationService NavigationService { get { return this.GetService<INavigationService>(); } }
public MainViewModel() { }
public void OnViewLoaded() {
NavigationService.Navigate("HomeView", null, this);
}
}
}
<UserControl x:Class="DXSample.View.HomeView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:lc="http://schemas.devexpress.com/winfx/2008/xaml/layoutcontrol"
xmlns:dxmvvm="http://schemas.devexpress.com/winfx/2008/xaml/mvvm"
xmlns:dxwui="http://schemas.devexpress.com/winfx/2008/xaml/windowsui"
xmlns:ViewModel="clr-namespace:DXSample.ViewModel"
mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="300"
DataContext="{dxmvvm:ViewModelSource Type={x:Type ViewModel:HomeViewModel}}">
<dxwui:PageAdornerControl Header="Home View">
<lc:TileLayoutControl>
<lc:Tile Size="Small" Command="{Binding NavigateDetailsCommand}">
<TextBlock Text="Details" HorizontalAlignment="Center" VerticalAlignment="Center" />
</lc:Tile>
</lc:TileLayoutControl>
</dxwui:PageAdornerControl>
</UserControl>
using DevExpress.Mvvm;
using DevExpress.Mvvm.POCO;
namespace DXSample.ViewModel {
public class DetailViewModel {
private INavigationService NavigationService { get { return this.GetService<INavigationService>(); } }
public void NavigateNextDetail() {
NavigationService.Navigate("NextDetailView", null, this);
}
public void NavigateBack() {
NavigationService.GoBack();
}
public bool CanNavigateBack() {
return NavigationService.CanGoBack;
}
public void NavigateForward() {
NavigationService.GoForward();
}
public bool CanNavigateForward() {
return NavigationService != null && NavigationService.CanGoForward;
}
}
}
<UserControl x:Class="DXSample.View.DetailView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:dxwui="http://schemas.devexpress.com/winfx/2008/xaml/windowsui"
xmlns:dxwuii="http://schemas.devexpress.com/winfx/2008/xaml/windowsui/internal"
xmlns:dxmvvm="http://schemas.devexpress.com/winfx/2008/xaml/mvvm"
xmlns:ViewModel="clr-namespace:DXSample.ViewModel"
mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="300"
DataContext="{dxmvvm:ViewModelSource Type={x:Type ViewModel:DetailViewModel}}">
<Grid>
<dxwui:PageAdornerControl Header="Detail View">
<dxwui:PageAdornerControl.HeaderTemplate>
<DataTemplate>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition/>
<ColumnDefinition Width="Auto" />
</Grid.ColumnDefinitions>
<TextBlock Text="{Binding}" />
<Button Grid.Column="1" Content="Go Forward" HorizontalAlignment="Right" FontSize="14" Command="{Binding DataContext.NavigateForwardCommand, RelativeSource={RelativeSource AncestorType=dxwuii:NavigationHeaderControl}}" />
</Grid>
</DataTemplate>
</dxwui:PageAdornerControl.HeaderTemplate>
<Button HorizontalAlignment="Center" VerticalAlignment="Center" Content="Next Detail View" Padding="4" Margin="2" Command="{Binding NavigateNextDetailCommand}"/>
</dxwui:PageAdornerControl>
</Grid>
</UserControl>
using DevExpress.Mvvm;
using DevExpress.Mvvm.POCO;
namespace DXSample.ViewModel {
public class HomeViewModel {
private INavigationService NavigationService { get { return this.GetService<INavigationService>(); } }
public HomeViewModel() { }
public void NavigateDetails() {
NavigationService.Navigate("DetailView", null, this);
}
}
}
Imports Microsoft.VisualBasic
Imports System
Imports DevExpress.Mvvm
Imports DevExpress.Mvvm.POCO
Namespace DXSample.ViewModel
Public Class HomeViewModel
Private ReadOnly Property NavigationService() As INavigationService
Get
Return Me.GetService(Of INavigationService)()
End Get
End Property
Public Sub New()
End Sub
Public Sub NavigateDetails()
NavigationService.Navigate("DetailView", Nothing, Me)
End Sub
End Class
End Namespace
Imports Microsoft.VisualBasic
Imports System
Imports DevExpress.Mvvm
Imports DevExpress.Mvvm.POCO
Namespace DXSample.ViewModel
Public Class MainViewModel
Private ReadOnly Property NavigationService() As INavigationService
Get
Return Me.GetService(Of INavigationService)()
End Get
End Property
Public Sub New()
End Sub
Public Sub OnViewLoaded()
NavigationService.Navigate("HomeView", Nothing, Me)
End Sub
End Class
End Namespace
Imports Microsoft.VisualBasic
Imports System
Imports DevExpress.Mvvm
Imports DevExpress.Mvvm.POCO
Namespace DXSample.ViewModel
Public Class DetailViewModel
Private ReadOnly Property NavigationService() As INavigationService
Get
Return Me.GetService(Of INavigationService)()
End Get
End Property
Public Sub NavigateNextDetail()
NavigationService.Navigate("NextDetailView", Nothing, Me)
End Sub
Public Sub NavigateBack()
NavigationService.GoBack()
End Sub
Public Function CanNavigateBack() As Boolean
Return NavigationService.CanGoBack
End Function
Public Sub NavigateForward()
NavigationService.GoForward()
End Sub
Public Function CanNavigateForward() As Boolean
Return NavigationService IsNot Nothing AndAlso NavigationService.CanGoForward
End Function
End Class
End Namespace