private async void FacadeNavigatingCancelEventHandler(object sender, NavigatingCancelEventArgs e)
{
DebugWrite();
object parameter = null;
try
{
parameter = SerializationService.Deserialize(e.Parameter?.ToString());
}
catch (Exception ex)
{
throw new Exception("Your parameter must be serializable. If it isn't, then use SessionState.", ex);
}
var deferral = new DeferralManager();
var args = new NavigatingEventArgs(deferral, e, Content as Page, e.SourcePageType, parameter, e.Parameter);
if (NavigationModeHint != NavigationMode.New)
{
args.NavigationMode = NavigationModeHint;
}
NavigationModeHint = NavigationMode.New;
_navigatingEventHandlers.ForEach(x => x(this, args));
await deferral.WaitForDeferralsAsync().ConfigureAwait(false);
e.Cancel = args.Cancel;
}
public void NoDeferrals_IsCompleted()
{
var dm = new DeferralManager();
var task = dm.WaitForDeferralsAsync();
Assert.True(task.IsCompleted);
}
private static async Task <bool> CallClassicOnNavigatingFrom(object viewmodel, NavigationMode mode, Page sourcePage, object sourceParameter, Type targetType, object targetParameter, bool suspending)
{
var deferral = new DeferralManager();
var navigatingEventArgs = new Classic.NavigatingEventArgs(deferral)
{
Page = sourcePage,
PageType = sourcePage?.GetType(),
Parameter = sourceParameter,
NavigationMode = mode,
TargetPageType = targetType,
TargetPageParameter = targetParameter,
Suspending = suspending,
};
try
{
var vm = viewmodel as Classic.INavigatingAwareAsync;
if (vm != null)
{
await vm.OnNavigatingFromAsync(navigatingEventArgs);
await deferral.WaitForDeferralsAsync();
}
}
catch
{
Debugger.Break();
}
return(navigatingEventArgs.Cancel);
}
// before navigate (cancellable)
async Task <bool> NavigatingFromAsync(bool suspending, NavigationMode mode)
{
DebugWrite($"Suspending: {suspending}");
var page = FrameFacadeInternal.Content as Page;
if (page != null)
{
// force (x:bind) page bindings to update
XamlUtils.UpdateBindings(page);
// call navagable override (navigating)
var dataContext = ResolveForPage(page);
if (dataContext != null)
{
dataContext.NavigationService = this;
dataContext.Dispatcher = this.GetDispatcherWrapper();
dataContext.SessionState = BootStrapper.Current.SessionState;
var deferral = new DeferralManager();
var args = new NavigatingEventArgs(deferral)
{
NavigationMode = mode,
PageType = FrameFacadeInternal.CurrentPageType,
Parameter = FrameFacadeInternal.CurrentPageParam,
Suspending = suspending,
};
await deferral.WaitForDeferralsAsync();
await dataContext.OnNavigatingFromAsync(args);
return(!args.Cancel);
}
}
return(true);
}
private async Task <bool> NavingFromAsync(Classic.INavigatingAwareAsync viewmodel, Page page, object currentParameter, bool suspending, NavigationMode navigationMode, Type targetPageType, object targetParameter)
{
var deferral = new DeferralManager();
var navigatingEventArgs = new Classic.NavigatingEventArgs(deferral)
{
Page = page,
Parameter = currentParameter,
Suspending = suspending,
NavigationMode = navigationMode,
TargetPageType = targetPageType,
TargetPageParameter = targetParameter,
};
try
{
await viewmodel.OnNavigatingFromAsync(navigatingEventArgs);
await deferral.WaitForDeferralsAsync();
}
catch
{
Debugger.Break();
}
return(navigatingEventArgs.Cancel);
}
public async Task CompletedDeferralFollowedByIncompleteDeferral_PreventsCompletion()
{
DeferralManager dm = new DeferralManager();
dm.DeferralSource.GetDeferral().Dispose();
IDisposable deferral = dm.DeferralSource.GetDeferral();
Task task = dm.WaitForDeferralsAsync();
await AsyncAssert.NeverCompletesAsync(task).ConfigureAwait(false);
}
public async Task CompletedDeferralFollowedByIncompleteDeferral_PreventsCompletion()
{
var dm = new DeferralManager();
dm.DeferralSource.GetDeferral().Dispose();
var deferral = dm.DeferralSource.GetDeferral();
var task = dm.WaitForDeferralsAsync();
await AsyncAssert.NeverCompletesAsync(task);
}
public async Task MultipleDeferralsWithOneIncomplete_PreventsCompletion()
{
DeferralManager dm = new DeferralManager();
IDisposable deferral1 = dm.DeferralSource.GetDeferral();
IDisposable deferral2 = dm.DeferralSource.GetDeferral();
Task task = dm.WaitForDeferralsAsync();
deferral1.Dispose();
await AsyncAssert.NeverCompletesAsync(task).ConfigureAwait(false);
}
public async Task MultipleDeferralsWithOneIncomplete_PreventsCompletion()
{
var dm = new DeferralManager();
var deferral1 = dm.DeferralSource.GetDeferral();
var deferral2 = dm.DeferralSource.GetDeferral();
var task = dm.WaitForDeferralsAsync();
deferral1.Dispose();
await AsyncAssert.NeverCompletesAsync(task);
}
public async Task DeferralCompleted_Completes()
{
var dm = new DeferralManager();
var deferral = dm.DeferralSource.GetDeferral();
var task = dm.WaitForDeferralsAsync();
Assert.False(task.IsCompleted);
deferral.Dispose();
await task;
}
public async Task <bool> NavingFromCancelsAsync(object viewmodel, NavigationMode mode, Page sourcePage, Type sourceType, object sourceParameter, Page targetPage, Type targetType, object targetParameter, bool suspending)
{
Services.NavigationService.NavigationService.DebugWrite();
if (sourcePage == null)
{
return(false);
}
else if (viewmodel == null)
{
return(false);
}
else if (viewmodel is Classic.INavigatingAwareAsync)
{
var deferral = new DeferralManager();
var navigatingEventArgs = new Classic.NavigatingEventArgs(deferral)
{
Page = sourcePage,
PageType = sourcePage?.GetType(),
Parameter = sourceParameter,
NavigationMode = mode,
TargetPageType = targetType,
TargetPageParameter = targetParameter,
Suspending = suspending,
};
try
{
var vm = viewmodel as Classic.INavigatingAwareAsync;
await vm?.OnNavigatingFromAsync(navigatingEventArgs);
await deferral.WaitForDeferralsAsync();
}
catch
{
Debugger.Break();
}
return(navigatingEventArgs.Cancel);
}
else if (viewmodel is Portable.IConfirmNavigationAsync)
{
var parameters = new Portable.NavigationParameters();
parameters.Add("NavigationMode", mode.ToPrismNavigationMode());
parameters.Add("SourceType", sourceType);
parameters.Add("SourceParameter", sourceParameter);
parameters.Add("TargetType", targetType);
parameters.Add("TargetParameter", targetParameter);
parameters.Add("Suspending", suspending);
var vm = viewmodel as Portable.IConfirmNavigationAsync;
return(!await vm?.CanNavigateAsync(parameters));
}
else
{
return(true);
}
}
public async Task MultipleDeferralsWithAllCompleted_Completes()
{
var dm = new DeferralManager();
var deferral1 = dm.DeferralSource.GetDeferral();
var deferral2 = dm.DeferralSource.GetDeferral();
var task = dm.WaitForDeferralsAsync();
deferral1.Dispose();
deferral2.Dispose();
await task;
}
protected async Task OnMyEventAsync()
{
if (MyEvent != null)
{
DeferralManager deferralManager = new DeferralManager();
MyEventArgs e = new MyEventArgs(deferralManager);
MyEvent(this, e);
await deferralManager.WaitForDeferralsAsync();
}
if (e.Change)
{
Console.WriteLine("Change occured");
}
}
private async void FacadeNavigatingCancelEventHandler(object sender, NavigatingCancelEventArgs args)
{
this.loggingService.WriteLine();
object parameter = null;
try
{
parameter = this.serializationService.Deserialize(args.Parameter?.ToString());
}
catch (Exception ex)
{
throw new Exception("Parameter must be serializable", ex);
}
var deferral = new DeferralManager();
var navigatingArgs = new NavigatingEventArgs(
deferral,
args,
this.Content as Page,
args.SourcePageType,
parameter,
args.Parameter);
if (this.NavigationModeHint != NavigationMode.New)
{
navigatingArgs.NavigationMode = this.NavigationModeHint;
}
this.NavigationModeHint = NavigationMode.New;
foreach (var handler in this.navigatingEventHandlers)
{
handler(this, navigatingArgs);
}
await deferral.WaitForDeferralsAsync().ConfigureAwait(false);
args.Cancel = navigatingArgs.Cancel;
}
// before navigate (cancellable)
async Task <bool> NavigatingFromAsync(Page page, INavigable dataContext, bool suspending, NavigationMode mode)
{
DebugWrite($"Suspending: {suspending}");
dataContext.NavigationService = this;
dataContext.Dispatcher = this.GetDispatcherWrapper();
dataContext.SessionState = BootStrapper.Current.SessionState;
var deferral = new DeferralManager();
var args = new NavigatingEventArgs(deferral)
{
NavigationMode = mode,
PageType = FrameFacadeInternal.CurrentPageType,
Parameter = FrameFacadeInternal.CurrentPageParam,
Suspending = suspending,
};
await deferral.WaitForDeferralsAsync();
await dataContext.OnNavigatingFromAsync(args);
return(!args.Cancel);
}
public async Task IncompleteDeferral_PreventsCompletion()
{
var dm = new DeferralManager();
var deferral = dm.DeferralSource.GetDeferral();
await AsyncAssert.NeverCompletesAsync(dm.WaitForDeferralsAsync());
}
internal Task WaitForDeferralsAsync()
{
return(_deferrals.WaitForDeferralsAsync());
}
public async Task IncompleteDeferral_PreventsCompletion()
{
DeferralManager dm = new DeferralManager();
IDisposable deferral = dm.DeferralSource.GetDeferral();
await AsyncAssert.NeverCompletesAsync(dm.WaitForDeferralsAsync()).ConfigureAwait(false);
}