private protected override void OnLoaded()
{
base.OnLoaded();
// TODO: Find a proper way to decide whether a CommandBar exists on canvas (within Page), or is mapped to the UINavigationController's NavigationBar.
CommandBar?commandBar = null;
_commandBar?.TryGetTarget(out commandBar);
if (_commandBar == null)
{
commandBar = TemplatedParent as CommandBar;
_commandBar = new WeakReference <CommandBar?>(commandBar);
_navigationBar = commandBar?.GetRenderer(RendererFactory).Native;
}
else
{
_navigationBar = commandBar?.ResetRenderer(RendererFactory).Native;
}
if (_navigationBar == null)
{
throw new InvalidOperationException("No NavigationBar from renderer");
}
_navigationBar.SetNeedsLayout();
var navigationBarSuperview = _navigationBar?.Superview;
// Allows the UINavigationController's NavigationBar instance to be moved to the Page. This feature
// is used in the context of the sample application to test NavigationBars outside of a NativeFramePresenter for
// UI Testing. In general cases, this should not happen as the bar may be moved back to to this presenter while
// another page is already visible, making this bar overlay on top of another.
if (FeatureConfiguration.CommandBar.AllowNativePresenterContent && (navigationBarSuperview == null || navigationBarSuperview is NativeCommandBarPresenter))
{
Content = _navigationBar;
}
var statusBar = StatusBar.GetForCurrentView();
statusBar.Showing += OnStatusBarChanged;
statusBar.Hiding += OnStatusBarChanged;
_statusBarSubscription.Disposable = Disposable.Create(() =>
{
statusBar.Showing -= OnStatusBarChanged;
statusBar.Hiding -= OnStatusBarChanged;
});
// iOS doesn't automatically update the navigation bar position when the status bar visibility changes.
void OnStatusBarChanged(StatusBar sender, object args)
{
_navigationBar !.SetNeedsLayout();
_navigationBar !.Superview.SetNeedsLayout();
}
}