/// <summary>
/// Craetes a new FamFrame and adds the resulting NavigationService to the
/// WindowWrapper collection. In addition, it optionally will setup the
/// shell back button to react to the nav of the Frame.
/// A developer should call this when creating a new/secondary frame.
/// The shell back button should only be setup one time.
/// </summary>
public Services.NavigationService.NavigationService NavigationServiceFactory(BackButton backButton, ExistingContent existingContent)
{
var frame = new Frame
{
Language = Windows.Globalization.ApplicationLanguages.Languages[0],
Content = (existingContent == ExistingContent.Include) ? Window.Current.Content : null,
};
var navigationService = new Services.NavigationService.NavigationService(frame);
WindowWrapper.Current().NavigationServices.Add(navigationService);
if (backButton == BackButton.Attach)
{
// TODO: unattach others
// update shell back when backstack changes
// only the default frame in this case because secondary should not dismiss the app
frame.RegisterPropertyChangedCallback(Frame.BackStackDepthProperty, (s, args) => UpdateShellBackButton());
// update shell back when navigation occurs
// only the default frame in this case because secondary should not dismiss the app
frame.Navigated += (s, args) => UpdateShellBackButton();
}
// this is always okay to check, default or not
// expire any state (based on expiry)
DateTime cacheDate;
// default the cache age to very fresh if not known
var otherwise = DateTime.MinValue.ToString();
if (DateTime.TryParse(navigationService.FrameFacade.GetFrameState(CacheDateKey, otherwise), out cacheDate))
{
var cacheAge = DateTime.Now.Subtract(cacheDate);
if (cacheAge >= CacheMaxDuration)
{
// clear state in every nav service in every view
foreach (var service in WindowWrapper.ActiveWrappers.SelectMany(x => x.NavigationServices))
{
service.FrameFacade.ClearFrameState();
}
}
}
else
{
// no date, that's okay
}
return(navigationService);
}
private void RaiseForwardRequested()
{
var args = new HandledEventArgs();
foreach (var frame in WindowWrapper.Current().NavigationServices.Select(x => x.FrameFacade))
{
frame.RaiseForwardRequested(args);
if (args.Handled)
{
return;
}
}
// default to first window
NavigationService.GoForward();
}
/// <summary>
/// Default Hardware/Shell Back handler overrides standard Back behavior
/// that navigates to previous app in the app stack to instead cause a backward page navigation.
/// Views or Viewodels can override this behavior by handling the BackRequested
/// event and setting the Handled property of the BackRequestedEventArgs to true.
/// </summary>
private void RaiseBackRequested(ref bool handled)
{
var args = new HandledEventArgs();
foreach (var frame in WindowWrapper.Current().NavigationServices.Select(x => x.FrameFacade).Reverse())
{
frame.RaiseBackRequested(args);
handled = args.Handled;
if (handled)
{
return;
}
}
// default to first window
NavigationService.GoBack();
}
private void RaiseForwardRequested()
{
var args = new HandledEventArgs();
ForwardRequested?.Invoke(null, args);
if (args.Handled)
{
return;
}
foreach (var frame in WindowWrapper.Current().NavigationServices.Select(x => x.FrameFacade))
{
frame.RaiseForwardRequested(args);
if (args.Handled)
{
return;
}
}
NavigationService.GoForward();
}
/// <summary>
/// Default Hardware/Shell Back handler overrides standard Back behavior
/// that navigates to previous app in the app stack to instead cause a backward page navigation.
/// Views or Viewodels can override this behavior by handling the BackRequested
/// event and setting the Handled property of the BackRequestedEventArgs to true.
/// </summary>
private void RaiseBackRequested(ref bool handled)
{
var args = new HandledEventArgs();
BackRequested?.Invoke(null, args);
if (handled = args.Handled)
{
return;
}
foreach (var frame in WindowWrapper.Current().NavigationServices.Select(x => x.FrameFacade).Reverse())
{
frame.RaiseBackRequested(args);
if (handled = args.Handled)
{
return;
}
}
NavigationService.GoBack();
}
private void RaiseForwardRequested()
{
DebugWrite();
var args = new HandledEventArgs();
ForwardRequested?.Invoke(null, args);
if (args.Handled)
{
return;
}
foreach (var navigationService in WindowWrapper.Current().NavigationServices)
{
navigationService.RaiseForwardRequested(args);
if (args.Handled)
{
return;
}
}
NavigationService.GoForward();
}
private void RaiseBackRequested(ref bool handled)
{
DebugWrite();
var args = new HandledEventArgs();
BackRequested?.Invoke(null, args);
if (handled = args.Handled)
{
return;
}
foreach (var navigationService in WindowWrapper.Current().NavigationServices.Select(x => x).Reverse())
{
navigationService.RaiseBackRequested(args);
if (handled = args.Handled)
{
return;
}
}
NavigationService.GoBack();
handled = true;
}
public static IDispatcherWrapper Current() => WindowWrapper.Current().Dispatcher;
// this is private because there's no reason for the developer to call this
private Frame InitializeFrame(ILaunchActivatedEventArgs e)
{
// do not recreate the frame
if (Window.Current.Content is Frame)
{
return(Window.Current.Content as Frame);
}
// first show the splash
var splashScreen = default(UIElement);
if (SplashFactory != null)
{
splashScreen = SplashFactory(e.SplashScreen);
Window.Current.Content = splashScreen;
Window.Current.Activate();
}
else
{
// if there is no SplashScreen then the default/static splash will show.
}
// in any case, next create a new, default frame
var defaultFrame = new Frame
{
Language = Windows.Globalization.ApplicationLanguages.Languages[0]
};
// set default frame as primary, default visual
Window.Current.Content = defaultFrame;
// next setup the default view
var navigationService = new Services.NavigationService.NavigationService(defaultFrame);
WindowWrapper.Current().NavigationServices.Add(navigationService);
// this anon method will be used to refresh the shell back button
Action updateShellBack = () =>
{
// show the shell back only if there is anywhere to go in the default frame
SystemNavigationManager.GetForCurrentView().AppViewBackButtonVisibility =
(ShowShellBackButton && NavigationService.Frame.CanGoBack)
? AppViewBackButtonVisibility.Visible
: AppViewBackButtonVisibility.Collapsed;
};
// update shell back when backstack changes
// only the default frame in this case because secondary should not dismiss the app
defaultFrame.RegisterPropertyChangedCallback(Frame.BackStackDepthProperty, (s, args) => updateShellBack());
// update shell back when navigation occurs
// only the default frame in this case because secondary should not dismiss the app
defaultFrame.Navigated += (s, args) => updateShellBack();
// expire any state (based on expiry)
DateTime cacheDate;
// default the cache age to very fresh if not known
var otherwise = DateTime.MinValue.ToString();
if (DateTime.TryParse(navigationService.FrameFacade.GetFrameState(CacheDateKey, otherwise), out cacheDate))
{
var cacheAge = DateTime.Now.Subtract(cacheDate);
if (cacheAge >= CacheMaxDuration)
{
// clear state in every nav service in every view
foreach (var service in WindowWrapper.ActiveWrappers.SelectMany(x => x.NavigationServices))
{
service.FrameFacade.ClearFrameState();
}
}
}
else
{
// no date, that's okay
}
// finally return our new frame
return(defaultFrame);
}
