protected override void OnElementChanged(ElementChangedEventArgs <Page> e)
{
base.OnElementChanged(e);
e.OldElement?.SendDisappearing();
if (e.NewElement != null)
{
if (e.OldElement == null)
{
Loaded += OnLoaded;
Tracker = new BackgroundTracker <FrameworkElement>(BackgroundProperty);
}
if (!string.IsNullOrEmpty(Element.AutomationId))
{
SetAutomationId(Element.AutomationId);
}
if (_loaded)
{
e.NewElement.SendAppearing();
}
}
}
public void SetElement(VisualElement element)
{
if (element != null && !(element is TabbedPage))
{
throw new ArgumentException("Element must be a TabbedPage", "element");
}
TabbedPage oldElement = Element;
Element = (TabbedPage)element;
if (oldElement != null)
{
oldElement.PropertyChanged -= OnElementPropertyChanged;
((INotifyCollectionChanged)oldElement.Children).CollectionChanged -= OnPagesChanged;
Control?.GetDescendantsByName <TextBlock>(TabBarHeaderTextBlockName).ForEach(t => { t.AccessKeyInvoked -= AccessKeyInvokedForTab; });
}
if (element != null)
{
if (Control == null)
{
Control = new FormsPivot {
Style = (global::Windows.UI.Xaml.Style)global::Windows.UI.Xaml.Application.Current.Resources["TabbedPageStyle"],
};
Control.SelectionChanged += OnSelectionChanged;
Tracker = new BackgroundTracker <Pivot>(global::Windows.UI.Xaml.Controls.Control.BackgroundProperty)
{
Element = (Page)element,
Control = Control,
Container = Control
};
Control.Loaded += OnLoaded;
Control.Unloaded += OnUnloaded;
}
Control.DataContext = Element;
OnPagesChanged(Element.Children,
new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
UpdateCurrentPage();
UpdateToolbarPlacement();
UpdateToolbarDynamicOverflowEnabled();
((INotifyCollectionChanged)Element.Children).CollectionChanged += OnPagesChanged;
element.PropertyChanged += OnElementPropertyChanged;
if (!string.IsNullOrEmpty(element.AutomationId))
{
Control.SetValue(global::Windows.UI.Xaml.Automation.AutomationProperties.AutomationIdProperty, element.AutomationId);
}
}
OnElementChanged(new VisualElementChangedEventArgs(oldElement, element));
}
public void SetElement(VisualElement element)
{
var newPage = element as CarouselPage;
if (element != null && newPage == null)
{
throw new ArgumentException("element must be a CarouselPage");
}
CarouselPage oldPage = Element;
Element = newPage;
if (oldPage != null)
{
oldPage.SendDisappearing();
((INotifyCollectionChanged)oldPage.Children).CollectionChanged -= OnChildrenChanged;
oldPage.PropertyChanged -= OnElementPropertyChanged;
}
if (newPage != null)
{
if (_tracker == null)
{
_tracker = new BackgroundTracker <FlipView>(BackgroundProperty)
{
Control = this, Container = this
};
}
_tracker.Element = newPage;
// Adding Items triggers the SelectionChanged event,
// which will reset the CurrentPage unless we tell it to ignore.
_fromUpdate = true;
for (var i = 0; i < newPage.Children.Count; i++)
{
Items.Add(newPage.Children[i]);
}
_fromUpdate = false;
((INotifyCollectionChanged)newPage.Children).CollectionChanged += OnChildrenChanged;
newPage.PropertyChanged += OnElementPropertyChanged;
UpdateCurrentPage();
newPage.SendAppearing();
}
OnElementChanged(new ElementChangedEventArgs <CarouselPage>(oldPage, newPage));
if (!string.IsNullOrEmpty(Element?.AutomationId))
{
SetValue(global::Windows.UI.Xaml.Automation.AutomationProperties.AutomationIdProperty, Element.AutomationId);
}
}
protected virtual void Dispose(bool disposing)
{
if (!disposing || _disposed)
{
return;
}
if (_tracker != null)
{
_tracker.Dispose();
_tracker = null;
}
_disposed = true;
Page?.SendDisappearing();
SetElement(null);
}