C# ScatterViewItem.BeginStoryboard方法代码示例

        //---------------------------------------------------------//
        /// <summary>
        /// Animates two ScatterViewItems together and then merges the content of both items into one ScatterViewItem.
        /// </summary>
        /// <param name="pieceRemaining">The piece that will remain after the join.</param>
        /// <param name="pieceBeingRemoved">The piece that will be removed as a result of the join.</param>
        private void JoinItems(ScatterViewItem pieceRemaining, ScatterViewItem pieceBeingRemoved)
        {
            // Simultaneous joins on the same pieces (as in the case where two matching pieces are dropped next 
            // to each other at the same time) eventually remove both matching pieces. Make sure only one join
            // happens at one time.
            if (!joinInProgress)
            {
                joinInProgress = true;

                Storyboard join = ((Storyboard)Resources["JoinPiece"]).Clone();

                foreach (AnimationTimeline animation in join.Children)
                {
                    // If this is a double animation, then it animates the piece's orientation
                    DoubleAnimation orientation = animation as DoubleAnimation;
                    if (orientation != null)
                    {
                        orientation.To = pieceRemaining.ActualOrientation;
                        orientation.From = pieceBeingRemoved.ActualOrientation;

                        // If two pieces are close in orientation, but seperated by the 0/360 line (i.e. 3 and 357) then don't spin the piece all the way around
                        if (Math.Abs(pieceRemaining.ActualOrientation - pieceBeingRemoved.ActualOrientation) > 180)
                        {
                            orientation.To += orientation.From > orientation.To ? 360 : -360;
                        }
                    }

                    // If this is a point animation, then it animates the piece's center
                    PointAnimation center = animation as PointAnimation;
                    if (center != null)
                    {
                        center.To = puzzleManager.CalculateJoinAnimationDestination(pieceRemaining, pieceBeingRemoved);
                    }

                    // Can't animate values that are set to NaN
                    if (double.IsNaN(pieceBeingRemoved.Orientation))
                    {
                        pieceBeingRemoved.Orientation = pieceBeingRemoved.ActualOrientation;
                    }

                    // Set up a callback that passes the ScatterViewItems that will be needed when the animation completes
                    join.Completed += delegate(object sender, EventArgs e)
                    {
                        OnJoinAnimationCompleted(pieceBeingRemoved, pieceRemaining);
                    };

                    pieceBeingRemoved.BeginStoryboard(join);
                }
            }
        }

        //---------------------------------------------------------//
        /// <summary>
        /// Adds a ScatterViewItem to the ScatterView, and animates it 
        /// on from the specified side of the screen (Left or Right).
        /// </summary>
        /// <param name="item">The item to add.</param>
        /// <param name="fromDirection">The direction from which puzzle pieces enter.</param>
        private void AddPiece(ScatterViewItem item, Direction fromDirection)
        {
            // Add the piece to the ScatterView at the correct location
            Debug.Assert(fromDirection == Direction.Right || fromDirection == Direction.Left);
                        
            double screenHeight = RootLayout.ActualHeight;
            double screenWidth = RootLayout.ActualWidth;
            item.Center = fromDirection == Direction.Right ? new Point(screenWidth, screenHeight / 2) : new Point(-100, screenHeight / 2);
            item.Orientation = random.Next(0, 360);
            scatter.Items.Add(item);

            // Load the animation
            Storyboard add = ((Storyboard)Resources["AddPiece"]).Clone();
            
            foreach (AnimationTimeline animation in add.Children)
            {
                // If this is a double animation, it animates the item's orientation
                DoubleAnimation orientation = animation as DoubleAnimation;
                if (orientation != null)
                {
                    // Spin the orientation a little.
                    orientation.To = item.Orientation + random.Next(-135, 135);
                }

                // If this is a point animation, then it animates the item's center
                PointAnimation center = animation as PointAnimation;
                if (center != null)
                {
                    // Get a random point to animate the item to
                    center.To = new Point(random.Next(0, (int)(screenHeight + 5)), random.Next(0, (int)screenHeight));
                }
            }

            // Set up a callback that passes the ScatterViewItem that will be needed when the animation completes
            add.Completed += delegate(object sender, EventArgs e)
            {
                OnAddAnimationCompleted(item);
            };

            // Start the animation
            item.BeginStoryboard(add, HandoffBehavior.SnapshotAndReplace);
        }