protected virtual INavigationContext CreateContextNavigateTo(NavigationEventArgsBase args)
{
IViewModel viewModelFrom = null, viewModelTo = null;
if (args.NavigationMode.IsClose())
{
viewModelFrom = args.Context.GetData(NavigationConstants.ViewModel);
}
else
{
viewModelTo = args.Context.GetData(NavigationConstants.ViewModel);
}
if (viewModelFrom == null)
{
viewModelFrom = CurrentViewModel;
}
if (args.NavigationMode == NavigationMode.Remove)
{
if (viewModelFrom != null)
{
return(new NavigationContext(NavigationType.Page, NavigationMode.Remove, viewModelFrom, null, this, args.Context));
}
Tracer.Error("Possible bug in navigation, navigate with mode Remove mode without ViewModel");
}
Guid viewModelId;
var vmType = GetViewModelTypeFromParameter(args.Parameter, out viewModelId);
if (viewModelTo == null && vmType != null)
{
viewModelTo = ViewModelProvider.TryGetViewModelById(viewModelId);
}
if (vmType == null)
{
if (args.Content != null)
{
var items = ViewMappingProvider.FindMappingsForView(args.Content.GetType(), false);
if (items.Count == 1)
{
var type = items[0].ViewModelType;
#if WINDOWS_UWP || XAMARIN_FORMS
if (!type.GetTypeInfo().IsGenericTypeDefinition)
#else
if (!type.IsGenericTypeDefinition)
#endif
{ vmType = type; }
}
}
if (vmType == null)
{
return(new NavigationContext(NavigationType.Page, args.NavigationMode, viewModelFrom, viewModelTo, this, args.Context));
}
}
return(new NavigationContext(NavigationType.Page, args.NavigationMode, viewModelFrom, viewModelTo, this, args.Context)
{
{ ViewModelTypeConstant, vmType }
});
}
protected virtual void NavigationServiceOnNavigated(object sender, NavigationEventArgsBase e)
{
string idOperation = null;
try
{
var context = CreateContextNavigateTo(CurrentViewModel, e);
idOperation = context.GetData(OperationIdConstant);
IOperationCallback callback = null;
if (idOperation == _currentOperationId)
{
callback = _currentCallback;
_currentCallback = null;
_navigationTargetVm = null;
_lastContext = null;
}
UpdateNavigationContext(callback, context.ViewModelTo, e, ref context);
OnNavigated(context);
}
finally
{
if (idOperation == _currentOperationId)
{
_currentOperationId = null;
var tcs = _navigatedTcs;
if (tcs != null)
{
_navigatedTcs = null;
tcs.TrySetResult(null);
}
}
}
}
public virtual void OnNavigated(NavigationEventArgsBase e)
{
EventHandler <INavigationService, NavigationEventArgsBase> handler = Navigated;
if (handler != null)
{
handler(this, e);
}
}
/// <summary>
/// Subscriber to the Navigated event.
/// </summary>
protected virtual void NavigationServiceOnNavigated(object sender, NavigationEventArgsBase e)
{
var callback = _currentCallback;
var vm = _navigationTargetVm;
var context = CreateContextNavigateTo(CurrentViewModel, vm, e);
UpdateNavigationContext(callback, vm, e, ref context);
OnNavigated(context);
}
private void RaiseNavigated(NavigationEventArgsBase args)
{
var navigated = Navigated;
if (navigated != null)
{
navigated(this, args);
}
}
private void RaiseNavigated(NavigationEventArgsBase args)
{
var handler = Navigated;
if (handler != null)
{
handler(this, args);
}
}
private void UpdateNavigationContext(NavigationEventArgsBase args, ref INavigationContext context)
{
var vmType = context.GetData(ViewModelTypeConstant);
if (vmType == null)
{
return;
}
var viewModel = GetViewModelForView(args, context.ViewModelTo, context, vmType);
if (!ReferenceEquals(context.ViewModelTo, viewModel))
{
context = new NavigationContext(NavigationType.Page, context.NavigationMode, context.ViewModelFrom, viewModel, context.NavigationProvider, args.Context);
}
}
private void NavigationServiceOnNavigated(object sender, NavigationEventArgsBase args)
{
try
{
if (!args.Context.Contains(NavigatedTaskConstant) && _unobservedNavigationTcs == null)
{
_unobservedNavigationTcs = new TaskCompletionSource <bool>();
}
var context = CreateContextNavigateTo(args);
UpdateNavigationContext(args, ref context);
OnNavigated(context);
}
finally
{
TryCompleteNavigationTask(args.Context, true);
}
}
protected virtual IViewModel GetViewModelForView([NotNull] NavigationEventArgsBase args,
[CanBeNull] IViewModel navigationViewModel, [NotNull] INavigationContext context, [NotNull] Type vmType)
{
var view = args.Content;
if (navigationViewModel != null)
{
ViewManager.InitializeViewAsync(navigationViewModel, view, context).WithTaskExceptionHandler(this);
return(navigationViewModel);
}
IViewModel vm = null;
if (CachePolicy != null)
{
vm = CachePolicy.TryTakeViewModelFromCache(context, view);
}
if (HasViewModel(view, vmType))
{
return((IViewModel)MugenMvvmToolkit.Infrastructure.ViewManager.GetDataContext(view));
}
if (vm == null)
{
IDataContext viewModelState = null;
#if WINDOWS_UWP
viewModelState = PlatformExtensions.GetViewModelState(view);
if (viewModelState != null)
{
PlatformExtensions.SetViewModelState(view, null);
}
#endif
vm = ViewModelProvider.RestoreViewModel(viewModelState, new DataContext
{
{ InitializationConstants.ViewModelType, vmType }
}, true);
}
if (vm != null)
{
ViewManager.InitializeViewAsync(vm, view, context).WithTaskExceptionHandler(this);
}
return(vm);
}
protected virtual IViewModel GetViewModelForView([NotNull] NavigationEventArgsBase args,
[CanBeNull] IViewModel navigationViewModel, [NotNull] INavigationContext context, [NotNull] Type vmType)
{
var view = args.Content;
if (navigationViewModel != null)
{
ViewManager.InitializeViewAsync(navigationViewModel, view, context);
return(navigationViewModel);
}
if (HasViewModel(view, vmType))
{
return((IViewModel)ToolkitExtensions.GetDataContext(view));
}
IDataContext viewModelState = null;
#if WINDOWS_UWP
viewModelState = UwpToolkitExtensions.GetViewModelState(view);
if (viewModelState != null)
{
UwpToolkitExtensions.SetViewModelState(view, null);
}
#endif
var vm = ViewModelProvider.RestoreViewModel(viewModelState, new DataContext
{
{ InitializationConstants.ViewModelType, vmType }
}, true);
if (vm != null)
{
ViewManager.InitializeViewAsync(vm, view, context);
if (viewModelState == null && !vm.Settings.Metadata.GetData(NavigationConstants.DoNotDisposeNoStateViewModel))
{
vm.RegisterNavigationOperation(OperationType.PageNavigation, context)
.ContinueWith <IViewModel>((viewModel, result) => viewModel.Dispose());
}
}
return(vm);
}
protected virtual IViewModel GetViewModelForView([NotNull] NavigationEventArgsBase args,
[CanBeNull] IViewModel navigationViewModel, [NotNull] INavigationContext context, [NotNull] Type vmType)
{
var view = args.Content;
if (navigationViewModel != null)
{
ViewManager.InitializeViewAsync(navigationViewModel, view).WithTaskExceptionHandler(this);
return(navigationViewModel);
}
//Trying to get from cache.
IViewModel vm = TryTakeViewModelFromCache(context, view);
if (HasViewModel(view, vmType))
{
return((IViewModel)ViewManagerEx.GetDataContext(view));
}
if (vm == null)
{
IDataContext viewModelState = null;
#if WINDOWS_PHONE || NETFX_CORE || WINDOWSCOMMON
viewModelState = PlatformExtensions.GetViewModelState(view);
if (viewModelState != null)
{
PlatformExtensions.SetViewModelState(view, null);
}
#endif
vm = ViewModelProvider.RestoreViewModel(viewModelState, new DataContext
{
{ InitializationConstants.ViewModelType, vmType }
}, false);
}
if (vm != null)
{
ViewManager.InitializeViewAsync(vm, view).WithTaskExceptionHandler(this);
}
return(vm);
}
protected virtual IViewModel GetViewModelForView([NotNull] NavigationEventArgsBase args,
[CanBeNull] IViewModel navigationViewModel, [NotNull] INavigationContext context, [NotNull] Type vmType)
{
var view = args.Content;
if (navigationViewModel != null)
{
ViewManager.InitializeViewAsync(navigationViewModel, view, context);
return(navigationViewModel);
}
if (HasViewModel(view, vmType))
{
return((IViewModel)ToolkitExtensions.GetDataContext(view));
}
IDataContext viewModelState = null;
#if WINDOWS_UWP
viewModelState = UwpToolkitExtensions.GetViewModelState(view);
if (viewModelState != null)
{
UwpToolkitExtensions.SetViewModelState(view, null);
}
#endif
var vm = ViewModelProvider.RestoreViewModel(viewModelState, new DataContext
{
{ InitializationConstants.ViewModelType, vmType }
}, true);
if (vm != null)
{
ViewManager.InitializeViewAsync(vm, view, context);
}
return(vm);
}
private void RaiseNavigated(NavigationEventArgsBase args)
{
Navigated?.Invoke(this, args);
}
private void UpdateNavigationContext(IOperationCallback callback, IViewModel navigationViewModel, NavigationEventArgsBase args, ref INavigationContext context)
{
var vmType = context.GetData(ViewModelTypeConstant);
if (vmType == null)
{
return;
}
var viewModel = GetViewModelForView(args, navigationViewModel, context, vmType);
if (!ReferenceEquals(context.ViewModelTo, viewModel))
{
context = new NavigationContext(NavigationType.Page, context.NavigationMode, context.ViewModelFrom, viewModel, context.NavigationProvider);
}
if (viewModel != null && callback != null)
{
RegisterOperationCallback(viewModel, callback, context);
}
}
protected virtual INavigationContext CreateContextNavigateTo(IViewModel viewModelFrom, NavigationEventArgsBase args)
{
string idOperation;
var vmType = GetViewModelTypeFromParameter(NavigationService.GetParameterFromArgs(args), out idOperation);
var viewModelTo = idOperation == _currentOperationId ? _navigationTargetVm : null;
if (vmType == null)
{
if (args.Content != null)
{
var items = _mappingProvider.FindMappingsForView(args.Content.GetType(), false);
if (items.Count == 1)
{
var type = items[0].ViewModelType;
#if WINDOWSCOMMON || XAMARIN_FORMS
if (!type.GetTypeInfo().IsGenericTypeDefinition)
#else
if (!type.IsGenericTypeDefinition)
#endif
{ vmType = type; }
}
}
if (vmType == null)
{
return new NavigationContext(NavigationType.Page, args.Mode, viewModelFrom, viewModelTo, this)
{
{ NavigationArgsConstant, args },
{ OperationIdConstant, idOperation }
}
}
;
}
return(new NavigationContext(NavigationType.Page, args.Mode, viewModelFrom, viewModelTo, this)
{
{ NavigationArgsConstant, args },
{ ViewModelTypeConstant, vmType },
{ OperationIdConstant, idOperation }
});
}
protected virtual INavigationContext CreateContextNavigateTo(IViewModel viewModelFrom, IViewModel viewModelTo, NavigationEventArgsBase args)
{
IDataContext parameters;
var vmType = GetViewModelTypeFromParameter(NavigationService.GetParameterFromArgs(args), out parameters);
if (vmType == null)
{
if (args.Content != null)
{
var items = _mappingProvider.FindMappingsForView(args.Content.GetType(), false);
if (items.Count == 1)
{
var type = items[0].ViewModelType;
#if NETFX_CORE || WINDOWSCOMMON || XAMARIN_FORMS
if (!type.GetTypeInfo().IsGenericTypeDefinition)
#else
if (!type.IsGenericTypeDefinition)
#endif
{ vmType = type; }
}
}
if (vmType == null)
{
return(new NavigationContext(args.Mode, viewModelFrom, viewModelTo, this, parameters));
}
}
return(new NavigationContext(args.Mode, viewModelFrom, viewModelTo, this, parameters)
{
{ NavigationArgsConstant, args },
{ ViewModelType, vmType }
});
}
public virtual void OnNavigated(NavigationEventArgsBase e)
{
Navigated?.Invoke(this, e);
}
