/**
  * Register a WebView to the current MaterialViewPagerAnimator
  * Listen to ObservableScrollViewCallbacks so give to $[observableScrollViewCallbacks] your ObservableScrollViewCallbacks if you already use one
  * For loadmore or anything else
  *
  * @param activity                      current context
  * @param webView                       the scrollable
  * @param observableScrollViewCallbacks use it if you want to get a callback of the RecyclerView
  */
 public static void RegisterWebView(Activity activity, ObservableWebView webView, IObservableScrollViewCallbacks observableScrollViewCallbacks) {
     if (activity != null && _hashMap.ContainsKey(activity)) {
         MaterialViewPagerAnimator animator;
         if (_hashMap.TryGetValue(activity, out animator) && animator != null) {
             animator.RegisterWebView(webView, observableScrollViewCallbacks);
         }
     }
 }
		public override void OnViewCreated(View view, Bundle savedInstanceState)
		{
			base.OnViewCreated(view, savedInstanceState);

			 mWebView = view.FindViewById<ObservableWebView>(Resources.Id.webView);

        //must be called before loadUrl()
        MaterialViewPagerHelper.PreLoadInjectHeader(mWebView);

			mWebView.SetWebViewClient();

        //have to inject header when WebView page loaded
        mWebView.setWebViewClient(new WebViewClient() {
            @Override
		public ObservableWebViewCallbacks(MaterialViewPagerAnimator materialViewPagerAnimator, ObservableWebView webView, IObservableScrollViewCallbacks observableScrollViewCallbacks)
		{
			_animator = materialViewPagerAnimator;
			_webView = webView;
			_observableScrollViewCallbacks = observableScrollViewCallbacks;
		}
		/**
		 * Register a WebView to the current MaterialViewPagerAnimator
		 * Listen to ObservableScrollViewCallbacks so give to $[observableScrollViewCallbacks] your ObservableScrollViewCallbacks if you already use one
		 * For loadmore or anything else
		 *
		 * @param webView                       the scrollable
		 * @param observableScrollViewCallbacks use it if you want to get a callback of the RecyclerView
		 */
		public void RegisterWebView(ObservableWebView webView, IObservableScrollViewCallbacks observableScrollViewCallbacks)
		{
			if (webView != null)
			{
				if (!ScrollViewList.Any())
					OnMaterialScrolled(webView, webView.GetCurrentScrollY());
				ScrollViewList.Add(webView);  //add to the scrollable list

				webView.SetScrollViewCallbacks(new ObservableWebViewCallbacks(this, webView, observableScrollViewCallbacks));
				SetScrollOffset(webView, -LastYOffset);
			}
		}