void InvokeOnNavigatedFrom(object item, NavigationContext navigationContext)
{
var navigationAwareItem = item as INavigationAware;
if (navigationAwareItem != null)
{
navigationAwareItem.OnNavigatedFrom(navigationContext);
}
var frameworkElement = item as FrameworkElement;
if (frameworkElement != null)
{
INavigationAware navigationAwareDataContext = frameworkElement.DataContext as INavigationAware;
if (navigationAwareDataContext != null)
{
navigationAwareDataContext.OnNavigatedFrom(navigationContext);
}
if (frameworkElement != null)
{
var viewModel = frameworkElement.DataContext;
Type viewModelType = viewModel.GetType();
MethodInfo methodInfo = viewModelType.GetMethod("DisposeEvents");
if (methodInfo != null)
{
methodInfo.Invoke(viewModel, null);
}
}
}
}
/// <summary>
/// Handles the navigation when we are moving TO a new view/viewmodel.
/// </summary>
/// <param name="view"></param>
/// <param name="viewModel"></param>
/// <param name="navMode"></param>
/// <param name="parameter"></param>
private void HandleOnNavigatingTo(FrameworkElement view, object viewModel, NavigationMode navMode, object parameter)
{
// See if the ViewModel participates in navigation-aware services.
INavigationAware navm = viewModel as INavigationAware;
if (navm != null)
{
IDictionary <string, object> stateDictionary = null;
if (StateManager != null)
{
string key = GenerateStateKey(PageNavigator.ViewModelKeyPrefix);
StateManager.LoadObject(key, viewModel);
stateDictionary = StateManager.GetDictionary(key, false);
}
navm.OnNavigatedTo(new NavigatedToEventArgs(navMode, parameter, stateDictionary));
}
// See if the VIEW participates in navigation-aware services.
INavigationAware naView = view as INavigationAware;
if (naView != null)
{
IDictionary <string, object> stateDictionary = null;
if (StateManager != null)
{
string key = GenerateStateKey(PageNavigator.PageKeyPrefix);
stateDictionary = StateManager.GetDictionary(key, false);
}
naView.OnNavigatedTo(new NavigatedToEventArgs(navMode, parameter, stateDictionary));
}
}
/// <summary>
/// 带参数导航
/// </summary>
/// <typeparam name="T">参数类型</typeparam>
/// <param name="regionName"></param>
/// <param name="viewID"></param>
/// <param name="parameter">参数实体</param>
public static void Navigate <T>(string regionName, string viewID, T parameter)
{
if (!m_RegionNameMapControl.ContainsKey(regionName))
{
throw new Exception($"不存在此RegionName {regionName}");
}
if (!m_ViewIDMapView.ContainsKey(viewID))
{
throw new Exception($"不存在此ViewID {viewID}");
}
Type viewType = m_ViewIDMapView[viewID];
ContentControl control = m_RegionNameMapControl[regionName];
object view = Activator.CreateInstance(viewType);
FrameworkElement fe = view as FrameworkElement;
if (fe != null)
{
INavigationAware <T> aware = fe.DataContext as INavigationAware <T>;
aware?.GetNavigationParameter(parameter);
}
control.Content = view;
}
protected async virtual Task HandleSuccessfulSave(T vm)
{
await NotifyUserThatSaveWentWell(vm);
INavigationAware navigationAwareVm = vm as INavigationAware;
if (vm != null)
{
_regionManager.Regions[RegionNames.ContentRegion].NavigationService.Journal.GoBack();
}
}
protected override void OnNavigatedFrom(NavigationEventArgs e)
{
INavigationAware vm = DataContext as INavigationAware;
if (vm != null)
{
vm.OnNavigatedFrom(e.Parameter, e.NavigationMode);
}
base.OnNavigatedFrom(e);
}
/// <summary>
/// Handles the OnNavigatingFrom event which notifies a page/ViewModel that we are
/// moving AWAY from that view.
/// </summary>
/// <param name="rootFrame"></param>
/// <param name="navMode"></param>
/// <param name="cancel"></param>
/// <param name="suspending"></param>
private void HandleOnNavigatingFrom(Frame rootFrame, NavigationMode navMode, ref bool cancel, bool suspending)
{
if (rootFrame.Content != null)
{
IDictionary <string, object> stateDictionary = null;
FrameworkElement fe = rootFrame.Content as FrameworkElement;
if (fe != null)
{
if (fe.DataContext != null)
{
// Attempt to save the object off.
if (StateManager != null)
{
string key = GenerateStateKey(ViewModelKeyPrefix);
StateManager.SaveObject(key, fe.DataContext);
stateDictionary = StateManager.GetDictionary(key, true);
}
// See if the ViewModel participates in navigation-aware services.
INavigationAware navm = fe.DataContext as INavigationAware;
if (navm != null)
{
var e = (suspending)
? new NavigatingFromEventArgs(navMode, cancel, stateDictionary)
: new NavigatingFromEventArgs(stateDictionary);
navm.OnNavigatingFrom(e);
cancel = e.Cancel;
}
}
// See if the VIEW participates in navigation-aware services.
INavigationAware naView = fe as INavigationAware;
if (naView != null)
{
// Save off the VIEW
stateDictionary = null;
if (StateManager != null)
{
string key = GenerateStateKey(PageKeyPrefix);
stateDictionary = StateManager.GetDictionary(key, false);
}
var e = (suspending)
? new NavigatingFromEventArgs(navMode, cancel, stateDictionary)
: new NavigatingFromEventArgs(stateDictionary);
naView.OnNavigatingFrom(e);
cancel = e.Cancel;
}
}
}
}
private void ExecuteSearch(string phrase)
{
var searchBar = SearchBarService.Current;
if (searchBar != null)
{
UriQuery query = new UriQuery(searchBar.Parameters.ToString());
query.Add(SearchBar.ValueParameter, phrase);
query.Add(SearchBar.IsFromSearchBarParameter, "true");
IRegion viewRegion = RegionManager.Regions[AppRegions.ViewRegion];
IRegionNavigationService navigation = viewRegion.NavigationService;
if (navigation.Journal.CurrentEntry != null)
{
if (navigation.Journal.CurrentEntry.Uri.OriginalString.StartsWith(searchBar.NavigationUri.OriginalString))
{
INavigationAware navAware = null;
var activeView = viewRegion.ActiveViews.FirstOrDefault();
if (activeView is INavigationAware)
{
navAware = activeView as INavigationAware;
}
else
{
FrameworkElement element = activeView as FrameworkElement;
if (element != null && element.DataContext is INavigationAware)
{
navAware = element.DataContext as INavigationAware;
}
}
if (navAware != null)
{
navAware.OnNavigatedFrom(new NavigationContext(navigation,
navigation.Journal.CurrentEntry.Uri));
navAware.OnNavigatedTo(new NavigationContext(navigation,
new Uri(
searchBar.NavigationUri.ToString() + query,
UriKind.RelativeOrAbsolute)));
return;
}
}
}
RegionManager.RequestNavigate(AppRegions.ViewRegion, searchBar.NavigationUri.ToString() + query);
}
}
private void NotifyOnNavigatedTo(object parameter)
{
FrameworkElement contentElement = frame.Content as FrameworkElement;
if (contentElement == null)
{
return;
}
INavigationAware navigationAwareContext = contentElement.DataContext as INavigationAware;
if (navigationAwareContext != null)
{
navigationAwareContext.OnNavigatedTo(parameter);
}
}
private void NotifyOnNavigatingFrom()
{
FrameworkElement contentElement = frame.Content as FrameworkElement;
if (contentElement == null)
{
return;
}
INavigationAware navigationAwareContext = contentElement.DataContext as INavigationAware;
if (navigationAwareContext != null)
{
navigationAwareContext.OnNavigatingFrom();
}
}
private void WireView(FrameworkElement view, Object viewModel, IDictionary <String, String> navigationParameters)
{
INavigationAware navigationAware = viewModel as INavigationAware;
if (navigationAware != null)
{
RoutedEventHandler handler = null;
handler = (o, e) =>
{
navigationAware.Navigated(navigationParameters);
view.Loaded -= handler;
};
view.Loaded += handler;
}
view.DataContext = viewModel;
}
protected virtual void HandleSuccessfulSave(T vm, int newId)
{
ICancelAwareViewViewModel cancelAwareViewViewModel = vm as ICancelAwareViewViewModel;
if (cancelAwareViewViewModel != null)
{
_regionManager.Regions[RegionNames.ContentRegion].RequestNavigate(cancelAwareViewViewModel.CancelNavigateToViewName);
}
else
{
INavigationAware navigationAwareVm = vm as INavigationAware;
if (vm != null)
{
_regionManager.Regions[RegionNames.ContentRegion].NavigationService.Journal.GoBack();
}
}
}
void InvokeOnNavigatedFrom(object item, NavigationContext navigationContext)
{
var navigationAwareItem = item as INavigationAware;
if (navigationAwareItem != null)
{
navigationAwareItem.OnNavigatedFrom(navigationContext);
}
var frameworkElement = item as FrameworkElement;
if (frameworkElement != null)
{
INavigationAware navigationAwareDataContext = frameworkElement.DataContext as INavigationAware;
navigationAwareDataContext?.OnNavigatedFrom(navigationContext);
}
}
private void NavigateBack(IEntityAwareViewViewModel vm)
{
ICancelAwareViewViewModel cancelAwareViewViewModel = vm as ICancelAwareViewViewModel;
if (cancelAwareViewViewModel != null)
{
_regionManager.Regions[RegionNames.ContentRegion].RequestNavigate(cancelAwareViewViewModel.CancelNavigateToViewName);
}
else
{
INavigationAware navigationAwareVm = vm as INavigationAware;
if (vm != null)
{
_regionManager.Regions[RegionNames.ContentRegion].NavigationService.Journal.GoBack();
}
}
}
private static void InvokeOnNavigationAwareElement(object item, Action <INavigationAware> invocation)
{
var navigationAwareItem = item as INavigationAware;
if (navigationAwareItem != null)
{
invocation(navigationAwareItem);
}
FrameworkElement frameworkElement = item as FrameworkElement;
if (frameworkElement != null)
{
INavigationAware navigationAwareDataContext = frameworkElement.DataContext as INavigationAware;
if (navigationAwareDataContext != null)
{
invocation(navigationAwareDataContext);
}
}
}
public void NavigateToWindow <T>(object parameter) where T : IView
{
// configure your IoC container to resolve a View for a given ViewModel
// i.e. container.Register<IPlotView, PlotWindow>(); in your
// composition root
IView view = container.Resolve <T>();
Window window = view as Window;
if (window != null)
{
window.Show();
}
INavigationAware nav = view as INavigationAware;
if (nav != null)
{
nav.NavigatedTo(parameter);
}
}
private async Task <NavigationResult> HandleViewModelNavigation(INavigationAware fromPageVM, INavigationAware toPageVM, INavigationParameters parameters)
{
if (fromPageVM != null)
{
try
{
fromPageVM.OnNavigatedFrom(parameters);
}
catch (Exception ex)
{
return(new NavigationResult()
{
IsSuccess = false, Exception = ex
});
}
}
if (toPageVM != null)
{
try
{
toPageVM.OnNavigatingTo(parameters);
toPageVM.OnNavigatedTo(parameters);
await toPageVM.OnNavigatedToAsync(parameters);
}
catch (Exception ex)
{
return(new NavigationResult()
{
IsSuccess = false, Exception = ex
});
}
}
return(new NavigationResult()
{
IsSuccess = true
});
}
private async Task <bool> navigateAsync(UserControl view, INavigationAware viewModel)
{
var previousView = _frame.Content;
var activator = viewModel as IActivate;
if (activator != null)
{
await activator.ActivateAsync();
}
_frame.Content = view;
var navigationAware = viewModel;
if (navigationAware != null && previousView != null)
{
navigationAware.NavigatedFrom(previousView.GetType());
}
await OnNavigatedAsync(view, viewModel, view.GetType(), previousView?.GetType());
return(true);
}
public async Task <bool> NavigateAsync(Type viewType, INavigationAware viewModel)
{
Tracer.Info($"Trying to navigate to {viewType.FullName}.");
var previousView = _frame.Content;
var success = await CanNavigateAsync(new NavigatingEventArgs(viewType, previousView?.GetType()));
if (!success)
{
Tracer.Info("Navigation failed.");
return(false);
}
var dispatcher = _frame.Dispatcher;
var pattern = new NavigationHandlerTaskSource(
handler => Navigated += handler,
handler => Navigated -= handler);
var view = _container.Resolve(viewType) as UserControl;
Guard.RequireIsNotNull(view, nameof(view));
if (dispatcher.CheckAccess())
{
success = await navigateAsync(view, viewModel);
}
else
{
await dispatcher.InvokeAsync(async() => success = await navigateAsync(view, viewModel));
}
await pattern.Task;
Tracer.Info($"Navigation {(success ? "succeeded" : "failed")}.");
return(success);
}
/// <summary>
/// Loads the content from specified uri.
/// </summary>
/// <param name="uri">The content uri</param>
/// <returns>
/// The loaded content.
/// </returns>
protected override Object LoadContent(Uri uri)
{
FrameworkElement view = null;
var viewInfo = this.viewLocater.LocateViewInfo(uri);
if (viewInfo != null)
{
var viewType = viewInfo.Item1;
var viewModelType = viewInfo.Item2;
var navigationParameters = viewInfo.Item3;
view = (FrameworkElement)this.resolver.Get(viewType); // get the view.
if (viewModelType != null)
{
Object viewModel = this.resolver.Get(viewModelType);
INavigationAware navigationAware = viewModel as INavigationAware;
if (navigationAware != null)
{
RoutedEventHandler handler = null;
handler = (o, e) =>
{
navigationAware.Navigated(navigationParameters);
view.Loaded -= handler;
};
view.Loaded += handler;
}
view.DataContext = viewModel;
}
}
return(view);
}
/// <summary>
/// Called when the implementer has been navigated to.
/// </summary>
/// <param name="args">Provides data for navigation methods and event handlers that cannot cancel the navigation request.</param>
private void NavigatedTo(NavigationEventArgs args)
{
if(previousPage != null)
previousPage.OnNavigatedFrom(args);
previousPage = GetNavigationAware(args.Content);
if (previousPage == null) return;
previousPage.OnNavigatedTo(args);
}
public void SetNavigationContext(INavigationAware navigationAwareVm)
{
_navigationAwareVm = navigationAwareVm;
}
