/// <summary>
/// The <see cref="Center"/> PropertyChangedCallback function.
/// </summary>
/// <param name="d">The <see cref="CarouselItem"/> object whose <see cref="Center"/> property changed.</param>
/// <param name="e">DependencyPropertyChangedEventArgs which contains the old and new values.</param>
private static void OnCenterPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
CarouselItem item = d as CarouselItem;
if (d != null)
{
item.CenterChanged((Point)e.NewValue);
}
}
/// <summary>
/// The <see cref="Axis"/> PropertyChangedCallback static function.
/// </summary>
/// <param name="d">The <see cref="CarouselItem"/> object whose <see cref="Axis"/> property changed.</param>
/// <param name="e">DependencyPropertyChangedEventArgs which contains the old and new values.</param>
private static void OnAxisPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
CarouselItem item = d as CarouselItem;
if (d != null)
{
item.AxisChanged((Size)e.NewValue);
}
}
/// <summary>
/// <see cref="Angle"/> PropertyChangedCallback static function.
/// </summary>
/// <param name="d">The <see cref="CarouselItem"/> object whose <see cref="Angle"/> property changed.</param>
/// <param name="e">DependencyPropertyChangedEventArgs which contains the old and new values.</param>
private static void OnAnglePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
CarouselItem item = d as CarouselItem;
if (d != null)
{
item.AngleChanged((double)e.OldValue, (double)e.NewValue);
}
}
// User click the item with left mouse button
void item_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
if (SelectedItemViewer != null)
{
CarouselItem item = sender as CarouselItem;
ItemSource source = item.Tag as ItemSource;
SelectedItemViewer.Source = source.ImageSource;
SelectedItemViewer.Title = source.Title;
SelectedItemViewer.NavigateUri = source.NavigateUri;
OnSelectedItemChanged(source);
}
}
/// <summary>
/// Create the total storyboard contains all item's animations.
/// </summary>
/// <param name="items">The carousel items collection.</param>
/// <param name="direction">The carousel turnning direction.</param>
/// <returns>The storyboard just created.</returns>
private Storyboard BuildStoryboard(UIElementCollection items, TurnDirection direction)
{
// The carousel storyboard
Storyboard sb = null;
if (this.Resources.Contains(CarouselStoryboardKey))
{
// if already in resources, get from resources
sb = this.Resources[CarouselStoryboardKey] as Storyboard;
// Must stop it before we change it
sb.Stop();
// and clear the children
sb.Children.Clear(); // because we rebuild all item
}
else
{
sb = new Storyboard();
// Add to resources dictionary
this.Resources.Add(CarouselStoryboardKey, sb);
}
// Now, we start build each item's storyboard
int itemsCount = items.Count;
double perAngle = _2PI / itemsCount;
double by = _2PI;
for (int i = 0; i < itemsCount; i++)
{
double angle = i * perAngle + Math.PI / 2;
// We only care the carouselitem
CarouselItem item = items[i] as CarouselItem;
if (item != null)
{
item.Angle = angle;
// Add item's storyboard to main storyboard
if (direction == TurnDirection.Clockwise)
{
sb.Children.Add(BuildStoryboard(item, by, Duration));
}
else
{
sb.Children.Add(BuildStoryboard(item, -by, Duration));
}
}
}
return(sb);
}
// The carousel item height changed
private void ItemHeightChanged(double itemHeight)
{
if (CarouselCanvas != null)
{
foreach (var item in CarouselCanvas.Children)
{
CarouselItem ci = item as CarouselItem;
if (ci != null)
{
ci.Width = itemHeight;
}
}
}
}
/// <summary>
/// Place a item to carousel canvas.
/// </summary>
/// <param name="item">The item will be placed.</param>
/// <returns>The <see cref="CarouselItem"/> just placed.</returns>
private CarouselItem PlaceItem(ItemSource item)
{
CarouselItem cItem = new CarouselItem();
cItem.Width = ItemWidth;
cItem.Height = ItemHeight;
cItem.Source = item.ImageSource;
cItem.Tag = item;
// Attach the handle
cItem.MouseLeftButtonDown += new MouseButtonEventHandler(item_MouseLeftButtonDown);
// Add item to carousel canvas
CarouselCanvas.Children.Add(cItem);
return(cItem);
}
/// <summary>
/// Build storyboard to animate the item.
/// </summary>
/// <param name="name">The name of the storyboard.</param>
/// <param name="from">The from angle.</param>
/// <param name="to">The end angle.</param>
/// <param name="duration">The duration of the animation.</param>
/// <returns>The builded storyboard.</returns>
//private Storyboard BuildStoryboard(CarouselItem item, double from, double to, Duration duration)
//{
// Storyboard storyboard = new Storyboard();
// //this.Resources.Add(name, storyboard);
// // Angle animation
// DoubleAnimation doubleAnimation = new DoubleAnimation();
// doubleAnimation.From = from;
// doubleAnimation.To = to;
// doubleAnimation.Duration = duration;
// doubleAnimation.RepeatBehavior = RepeatBehavior.Forever;
// // Set storyboard target property
// storyboard.Children.Add(doubleAnimation);
// Storyboard.SetTarget(doubleAnimation, item);
// Storyboard.SetTargetProperty(doubleAnimation, new PropertyPath("Angle"));
// return storyboard;
//}
/// <summary>
/// Build storyboard to animate the item.
/// </summary>
/// <param name="name">The name of the storyboard.</param>
/// <param name="by">The total amount by which the animation changes its starting value.</param>
/// <returns>The builded storyboard.</returns>
private Storyboard BuildStoryboard(CarouselItem item, double by, Duration duration)
{
Storyboard storyboard = new Storyboard();
//this.Resources.Add(name, storyboard);
// Angle animation
DoubleAnimation doubleAnimation = new DoubleAnimation();
doubleAnimation.By = by;
doubleAnimation.Duration = duration;
doubleAnimation.RepeatBehavior = RepeatBehavior.Forever;
// Set storyboard target property
storyboard.Children.Add(doubleAnimation);
Storyboard.SetTarget(doubleAnimation, item);
Storyboard.SetTargetProperty(doubleAnimation, new PropertyPath("Angle"));
return(storyboard);
}
/// <summary>
/// Turnning one step in specifies direction.
/// </summary>
/// <param name="direction">The turnning direction.</param>
/// <remarks>You can call this function only
/// the <see cref="AutoTurn"/> is set to <c>false</c>.</remarks>
public void TrunOnStep(TurnDirection direction)
{
if (AutoTurn)
{
return;
}
if (CarouselCanvas != null)
{
double perAngle = _2PI / CarouselCanvas.Children.Count;
foreach (var item in CarouselCanvas.Children)
{
CarouselItem cItem = item as CarouselItem;
if (cItem != null)
{
if (direction == TurnDirection.Clockwise)
{
cItem.Angle += perAngle;
}
else
{
cItem.Angle -= perAngle;
}
// if overceed 2 PI, then adjust it
if (cItem.Angle > _2PI)
{
cItem.Angle -= _2PI;
}
else if (cItem.Angle < -_2PI)
{
cItem.Angle += _2PI;
}
}
}
}
}
// The item collection changed
private void Items_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
if (CarouselCanvas != null)
{
switch (e.Action)
{
case NotifyCollectionChangedAction.Add:
// Add item to collection
{
// X and Y axis of the ellipse
double radiusX = (this.CarouselCanvas.ActualWidth - 2 * ItemWidth
- (Padding.Left + Padding.Right)) / 2;
double radiusY = (this.CarouselCanvas.ActualHeight - 2 * ItemHeight
- (Padding.Top + Padding.Bottom)) / 2;
// center point of the ellipse
double centerX = radiusX + ItemWidth / 2 + Padding.Left;
double centerY = radiusY + Padding.Top;
Point center = new Point(centerX, centerY);
Size axis = new Size(radiusX, radiusY);
int count = e.NewItems.Count;
for (int i = 0; i < count; i++)
{
CarouselItem cItem = PlaceItem(e.NewItems[i] as ItemSource);
cItem.Center = center;
cItem.Axis = axis;
}
Storyboard sb = BuildStoryboard(CarouselCanvas.Children, this.TurnDirection);
if (this.AutoTurn)
{
sb.Begin();
}
}
break;
case NotifyCollectionChangedAction.Remove:
// Remove item from collection
{
int count = e.OldItems.Count;
for (int i = 0; i < count; i++)
{
CarouselCanvas.Children.RemoveAt(e.OldStartingIndex + i);
}
Storyboard sb = BuildStoryboard(CarouselCanvas.Children, this.TurnDirection);
if (this.AutoTurn)
{
sb.Begin();
}
}
break;
case NotifyCollectionChangedAction.Replace:
// Replace item
{
int count = e.OldItems.Count;
for (int i = 0; i < count; i++)
{
CarouselItem item = CarouselCanvas.Children[e.OldStartingIndex + i] as CarouselItem;
item.Source = (e.NewItems[i] as ItemSource).ImageSource;
}
}
break;
case NotifyCollectionChangedAction.Reset:
// Reset the collection
{
// do nothing
}
break;
}
}
}
