private void Setup()
{
delayDistance = 0.0f;
maxDelay = 0.0f;
lastContentOffset = 0.0f;
state = NavigationBarState.Expanded;
ShouldScrollWhenContentFits = false;
ExpandOnActive = true;
ScrollingEnabled = true;
}
public override void ScrollingNavigationStateChanged(NavigationBarState state)
{
Console.WriteLine("Navigation bar state changed: " + state);
}
public override void ScrollingNavigationStateChanged (NavigationBarState state)
{
Console.WriteLine ("Navigation bar state changed: " + state);
}
/// <summary>
/// Start scrolling
/// Enables the scrolling by observing a view
/// </summary>
/// <param name="scrollableView">The view with the scrolling content that will be observed.</param>
/// <param name="delay">The delay expressed in points that determines the scrolling resistance. Defaults to `0`.</param>
/// <param name="scrollSpeedFactor">This factor determines the speed of the scrolling content toward the navigation bar animation.</param>
/// <param name="followers">An array of `UIView`s that will follow the navbar.</param>
public void FollowScrollView(UIView scrollableView, double delay, double scrollSpeedFactor, UIView[] followers)
{
this.scrollableView = scrollableView;
var recognizer = new UIPanGestureRecognizer(OnPan);
recognizer.ShouldRecognizeSimultaneously = delegate {
// Enables the scrolling of both the content and the navigation bar
return(true);
};
recognizer.ShouldReceiveTouch = delegate {
// Only scrolls the navigation bar with the content when `scrollingEnabled` is true
return(ScrollingEnabled);
};
recognizer.ShouldBegin = delegate {
// Begin scrolling only if the direction is vertical (prevents conflicts with horizontal scroll views)
var velocity = gestureRecognizer.VelocityInView(gestureRecognizer.View);
return(Math.Abs(velocity.Y) > Math.Abs(velocity.X));
};
recognizer.MaximumNumberOfTouches = 1;
gestureRecognizer = recognizer;
scrollableView.AddGestureRecognizer(gestureRecognizer);
willResignActiveObserver = NSNotificationCenter.DefaultCenter.AddObserver(UIApplication.WillResignActiveNotification, notification => {
previousState = state;
});
didBecomeActiveObserver = NSNotificationCenter.DefaultCenter.AddObserver(UIApplication.DidBecomeActiveNotification, notification => {
if (ExpandOnActive)
{
ShowNavbar(false);
}
else
{
if (previousState == NavigationBarState.Collapsed)
{
HideNavbar(false);
}
}
});
deviceOrientationDidChange = NSNotificationCenter.DefaultCenter.AddObserver(UIDevice.OrientationDidChangeNotification, notification => {
ShowNavbar();
});
maxDelay = (nfloat)delay;
delayDistance = (nfloat)delay;
this.scrollSpeedFactor = (nfloat)scrollSpeedFactor;
ScrollingEnabled = true;
// Save TabBar state (the state is changed during the transition and restored on compeltion)
if (followers == null)
{
Followers = new UIView[0];
}
else
{
var tab = followers.OfType <UITabBar> ().FirstOrDefault();
if (tab != null)
{
sourceTabBar = new UITabBar(tab.Frame);
sourceTabBar.Translucent = tab.Translucent;
}
Followers = followers;
}
}
public virtual void ScrollingNavigationStateChanged(NavigationBarState state)
{
}
public virtual void ScrollingNavigationStateChanged (NavigationBarState state)
{
}
