private List <ViewModelBase> SetBingingContextForChildren <TParentViewModel, TParam, TResult>(
Page view,
ViewModelBase parentViewModel,
TParam param,
Action <TParentViewModel> parentViewModelInitialization,
CallbackParam <TResult> callbackParam)
where TParentViewModel : ViewModelBase
{
var resultChildren = new List <ViewModelBase>();
var childViews = view is TabbedPage tabbedPage
? tabbedPage.Children
: view is FlyoutPage flyoutPage
? new[] { flyoutPage.Flyout, flyoutPage.Detail }
: Array.Empty <Page>();
foreach (var childView in childViews)
{
var currentView = childView is NavigationPage navigationPage ? navigationPage.RootPage : childView;
var currentViewModel = null as ViewModelBase;
if (!currentView.GetType().IsDefined(typeof(ParentBindingContextAttribute)))
{
var viewModelType = _navigationMapper.GetViewModelTypeFor(currentView);
currentViewModel = (ViewModelBase)_resolver.Resolve(viewModelType, param);
if (currentViewModel is TParentViewModel parentViewModelType)
{
parentViewModelInitialization?.Invoke(parentViewModelType);
}
currentView.BindingContext = currentViewModel;
currentView.Appearing += (sender, args) => currentViewModel.OnAppearing();
currentView.Appearing += async(sender, args) => await currentViewModel.OnAppearingAsync();
currentView.Disappearing += (sender, args) => currentViewModel.OnDisappearing();
currentView.Disappearing += async(sender, args) => await currentViewModel.OnDisappearingAsync();
}
var children = SetBingingContextForChildren(
currentView,
currentViewModel ?? parentViewModel,
param,
parentViewModelInitialization,
callbackParam);
if (currentViewModel != null)
{
resultChildren.Add(currentViewModel);
_viewModelWrapperStorage.Add(currentViewModel,
new ViewModelWrapper <TResult>(callbackParam)
{
Parent = parentViewModel,
Children = children
});
}
else
{
resultChildren.AddRange(children);
}
}
return(resultChildren);
}
