导航

切换动画，相关的过渡动画，是淡入淡出的效果

   private void Frame_Navigating(object sender, NavigatingCancelEventArgs e)

        {

            if (Content != null && !_allowDirectNavigation)

            {

                e.Cancel = true;

                _navArgs = e;

                this.IsHitTestVisible = false;

                DoubleAnimation da = new DoubleAnimation(0.3d, new Duration(TimeSpan.FromMilliseconds(100)));

                da.Completed += FadeOutCompleted;

                this.BeginAnimation(OpacityProperty, da);



            }

            _allowDirectNavigation = false;

        }



        private void FadeOutCompleted(object sender, EventArgs e)

        {

            (sender as AnimationClock).Completed -= FadeOutCompleted;



            this.IsHitTestVisible = true;



            _allowDirectNavigation = true;

            switch (_navArgs.NavigationMode)

            {

                case NavigationMode.New:

                    if (_navArgs.Uri == null)

                    {

                        this.myFrame.NavigationService.Navigate(_navArgs.Content);

                    }

                    else

                    {

                        this.myFrame.NavigationService.Navigate(_navArgs.Uri);

                    }

                    break;

                case NavigationMode.Back:

                    this.myFrame.NavigationService.GoBack();

                    break;



                case NavigationMode.Forward:

                    this.myFrame.NavigationService.GoForward();

                    break;

                case NavigationMode.Refresh:

                    this.myFrame.NavigationService.Refresh();

                    break;

            }



            Dispatcher.BeginInvoke(DispatcherPriority.Loaded,

                (ThreadStart)delegate()

                {

                    DoubleAnimation da = new DoubleAnimation(1.0d, new Duration(TimeSpan.FromMilliseconds(200)));

                    this.BeginAnimation(OpacityProperty, da);

                });

        }





        private bool _allowDirectNavigation = false;

        private NavigatingCancelEventArgs _navArgs = null;

 

场景：某个导航页面中的按钮点击完成之后使Frame的Visibility为Collapsed

最初始的想法是从Page页面中获取宿主控件然后对宿主控件即Frame直接进行操作

查阅MSDN之后没有找到相对应的方法或者属性，只能修改宿主的长宽及ICON

所以变通的想到使用导航结束的事件来传递消息，来使Frame能够获取想要传达的信息，需要按照特定约定

约定：当导航结束后，myFrame_Navigated事件中查看Frame的Content如果是Page且Visibility为Collapsed则改变Frame的Visibility

   private void myFrame_Navigated(object sender, NavigationEventArgs e)

        {

            Page page = this.myFrame.Content as Page;

            if (page == null)

                return;

            if (page.Visibility == Visibility.Collapsed)

            {

                this.Visibility = Visibility.Collapsed;

                this.myFrame.NavigationService.GoBack();

            }

        }