protected virtual void HandleOpenedViewModels(INavigationContext context)
{
var viewModelFrom = context.GetData(NavigationConstants.DoNotTrackViewModelFrom) ? null : context.ViewModelFrom;
var viewModelTo = context.GetData(NavigationConstants.DoNotTrackViewModelTo) ? null : context.ViewModelTo;
lock (_openedViewModels)
{
List <WeakReference> list;
if (!_openedViewModels.TryGetValue(context.NavigationType, out list))
{
list = new List <WeakReference>();
_openedViewModels[context.NavigationType] = list;
}
if (context.NavigationMode == NavigationMode.New && viewModelTo != null)
{
list.Add(ServiceProvider.WeakReferenceFactory(viewModelTo));
}
else if ((context.NavigationMode == NavigationMode.Refresh || context.NavigationMode == NavigationMode.Back) && viewModelTo != null)
{
WeakReference viewModelRef = null;
for (int i = 0; i < list.Count; i++)
{
var target = list[i].Target as IViewModel;
if (target == null || ReferenceEquals(target, viewModelTo))
{
if (target != null)
{
viewModelRef = list[i];
}
list.RemoveAt(i);
--i;
}
}
if (viewModelRef == null)
{
viewModelRef = ServiceProvider.WeakReferenceFactory(viewModelTo);
}
list.Add(viewModelRef);
}
if (context.NavigationMode.IsClose() && viewModelFrom != null)
{
for (int i = 0; i < list.Count; i++)
{
var target = list[i].Target as IViewModel;
if (target == null || ReferenceEquals(target, viewModelFrom))
{
list.RemoveAt(i);
--i;
}
}
}
}
}
protected virtual void HandleOpenedViewModels(INavigationContext context)
{
var viewModelFrom = context.GetData(NavigationConstants.DoNotTrackViewModelFrom) ? null : context.ViewModelFrom;
var viewModelTo = context.GetData(NavigationConstants.DoNotTrackViewModelTo) ? null : context.ViewModelTo;
lock (OpenedViewModels)
{
List <WeakOpenedViewModelInfo> list;
if (!OpenedViewModels.TryGetValue(context.NavigationType, out list))
{
list = new List <WeakOpenedViewModelInfo>();
OpenedViewModels[context.NavigationType] = list;
}
if (viewModelTo != null && (context.NavigationMode == NavigationMode.Refresh || context.NavigationMode == NavigationMode.Back || context.NavigationMode == NavigationMode.New))
{
WeakOpenedViewModelInfo viewModelRef = null;
for (int i = 0; i < list.Count; i++)
{
var target = list[i].ViewModel;
if (target == null || ReferenceEquals(target, viewModelTo))
{
if (target != null)
{
viewModelRef = list[i];
}
list.RemoveAt(i);
--i;
}
}
if (viewModelRef == null)
{
viewModelRef = new WeakOpenedViewModelInfo(viewModelTo, context.NavigationProvider, context.NavigationType);
}
list.Add(viewModelRef);
}
if (viewModelFrom != null && context.NavigationMode.IsClose())
{
for (int i = 0; i < list.Count; i++)
{
var target = list[i].ViewModel;
if (target == null || ReferenceEquals(target, viewModelFrom))
{
list.RemoveAt(i);
--i;
}
}
}
}
}
protected virtual void OnNavigatedInternal(INavigationContext context)
{
(context.ViewModelFrom as INavigableViewModel)?.OnNavigatedFrom(context);
(context.ViewModelTo as INavigableViewModel)?.OnNavigatedTo(context);
if (context.NavigationMode.IsClose() && context.ViewModelFrom != null)
{
OnClosed(context.ViewModelFrom, context);
if (context.NavigationType.Operation != null && !context.GetData(NavigationConstants.SuppressNavigationCallbackOnClose))
{
var operationResult = OperationResult.CreateResult <object>(context.NavigationType.Operation, context.ViewModelFrom, null, context);
CallbackManager.SetResult(operationResult);
}
}
}
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 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);
}
}
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);
}
