| public static ExecuteOnLayoutUpdated ( global::Xamarin.Forms.VisualElement element, EventHandler handler ) : void | ||
| element | global::Xamarin.Forms.VisualElement | |
| handler | EventHandler | |
| return | void | |
/// <summary>
/// Executes the handler the next time the view's LayoutUpdated event fires.
/// </summary>
/// <param name="view">The view.</param>
/// <param name="handler">The handler.</param>
public virtual void ExecuteOnLayoutUpdated(object view, Action <object> handler)
{
var element = view as FrameworkElement;
if (element != null)
{
View.ExecuteOnLayoutUpdated(element, (s, e) => handler(s));
}
}
/// <summary>
/// Occurs after navigation
/// </summary>
/// <param name="sender"> The event sender. </param>
/// <param name="e"> The event args. </param>
protected virtual void OnNavigated(object sender, NavigationEventArgs e)
{
if (e.Content == null)
{
return;
}
ViewLocator.InitializeComponent(e.Content);
var viewModel = ViewModelLocator.LocateForView(e.Content);
if (viewModel == null)
{
return;
}
var view = e.Content as Page;
if (view == null)
{
throw new ArgumentException("View '" + e.Content.GetType().FullName + "' should inherit from Page or one of its descendents.");
}
if (treatViewAsLoaded)
{
view.SetValue(View.IsLoadedProperty, true);
}
TryInjectParameters(viewModel, e.Parameter);
ViewModelBinder.Bind(viewModel, view, null);
var activator = viewModel as IActivate;
if (activator != null)
{
activator.Activate();
}
var viewAware = viewModel as IViewAware;
if (viewAware != null)
{
View.ExecuteOnLayoutUpdated(view, (s, a) => viewAware.OnViewReady(view));
}
GC.Collect(); // Why?
}
/// <summary>
/// Occurs after navigation
/// </summary>
/// <param name="sender"> The event sender. </param>
/// <param name="e"> The event args. </param>
protected virtual void OnNavigated(object sender, NavigationEventArgs e)
{
if (e.Uri.IsAbsoluteUri || e.Content == null)
{
return;
}
ViewLocator.InitializeComponent(e.Content);
var viewModel = ViewModelLocator.LocateForView(e.Content);
if (viewModel == null)
{
return;
}
var page = e.Content as PhoneApplicationPage;
if (page == null)
{
throw new ArgumentException("View '" + e.Content.GetType().FullName + "' should inherit from PhoneApplicationPage or one of its descendents.");
}
if (treatViewAsLoaded)
{
page.SetValue(View.IsLoadedProperty, true);
}
TryInjectQueryString(viewModel, page);
ViewModelBinder.Bind(viewModel, page, null);
var activator = viewModel as IActivate;
if (activator != null)
{
activator.Activate();
}
var viewAware = viewModel as IViewAware;
if (viewAware != null)
{
View.ExecuteOnLayoutUpdated(page, (s, a) => viewAware.OnViewReady(page));
}
GC.Collect();
}
/// <summary>
/// Occurs after navigation
/// </summary>
/// <param name="sender"> The event sender. </param>
/// <param name="e"> The event args. </param>
protected virtual void OnNavigated(object sender, NavigationEventArgs e)
{
if (e.Uri.IsAbsoluteUri || e.Content == null)
{
return;
}
ViewLocator.InitializeComponent(e.Content);
// Do not use LocateForView because Frame control already has its
// parent's DataContext. Use LocateForViewType instead.
var viewModel = ViewModelLocator.LocateForViewType(e.Content.GetType());
//var viewModel = ViewModelLocator.LocateForView(e.Content);
if (viewModel == null)
{
if (System.Diagnostics.Debugger.IsAttached)
{
var msg = "'" + e.Content.GetType().FullName + "' must be registered in the bootstrapper (or INavigationService might never get injected)";
var exc = new InvalidOperationException(msg);
LogManager.GetLog(typeof(FrameAdapter)).Error(exc);
throw exc;
}
return;
}
// Inject dependency properties
IoC.BuildUp(viewModel);
#if WINDOWS_PHONE
var page = e.Content as PhoneApplicationPage;
#else
var page = e.Content as Page;
#endif
if (page == null)
{
throw new ArgumentException("View '" + e.Content.GetType().FullName + "' should inherit from PhoneApplicationPage or one of its descendents.");
}
if (treatViewAsLoaded)
{
page.SetValue(View.IsLoadedProperty, true);
}
TryInjectQueryString(viewModel, page);
ViewModelBinder.Bind(viewModel, page, null);
var activator = viewModel as IActivate;
if (activator != null)
{
activator.Activate();
}
#if WINDOWS_PHONE || WinRT
var page = e.Content as PhoneApplicationPage;
var viewAware = viewModel as IViewAware;
if (viewAware != null)
{
View.ExecuteOnLayoutUpdated(page, (s, a) => viewAware.OnViewReady(page));
}
#endif
GC.Collect();
}