private void ShowItems()
{
if (this.enteringItem != null)
{
this.enteringItem.Opacity = 1;
this.enteringItem = null;
}
}
private void ScrollSelected()
{
PathListBox pathListBox = this.AssociatedObject as PathListBox;
if (pathListBox == null)
{
return;
}
PathListBoxItem newItem = (PathListBoxItem)pathListBox.ItemContainerGenerator.ContainerFromItem(pathListBox.SelectedItem);
// find the item on the path that is closest to the position
PathListBoxItem closestItem = null;
PathListBoxItem pathListBoxItem;
for (int i = 0; i < pathListBox.Items.Count; i++)
{
pathListBoxItem = (PathListBoxItem)pathListBox.ItemContainerGenerator.ContainerFromIndex(i);
if (pathListBoxItem != null && pathListBoxItem.IsArranged)
{
if (closestItem == null)
{
closestItem = pathListBoxItem;
}
else if (Math.Abs(pathListBoxItem.LocalOffset - this.DesiredOffset) < Math.Abs(closestItem.LocalOffset - this.DesiredOffset))
{
closestItem = pathListBoxItem;
}
}
}
if (closestItem == null || newItem == null || !newItem.IsArranged || !closestItem.IsArranged)
{
return;
}
int increment = 0;
if (newItem.GlobalOffset < closestItem.GlobalOffset && newItem.GlobalIndex > closestItem.GlobalIndex)
{
increment = -(pathListBox.Items.Count - newItem.GlobalIndex + closestItem.GlobalIndex);
}
else if (newItem.GlobalOffset > closestItem.GlobalOffset && newItem.GlobalIndex < closestItem.GlobalIndex)
{
increment = (pathListBox.Items.Count - closestItem.GlobalIndex + newItem.GlobalIndex);
}
else
{
increment = newItem.GlobalIndex - closestItem.GlobalIndex;
}
bool hideEnteringItem = this.HideEnteringItem;
this.HideEnteringItem = false;
Scroll(increment);
this.HideEnteringItem = hideEnteringItem;
}
/// <summary>
/// Finds the item that is laid out at the end of the specified layout path.</summary>
/// <param name=”layoutPathIndex”> The specified layout path.</param>
/// <returns> The global index of the item.</returns>
public static int GetLastArrangedIndex(this PathListBox pathListBox, int layoutPathIndex)
{
if (pathListBox == null)
{
return(0);
}
PathListBoxItem pathListBoxItem;
PathListBoxItem lastItemArranged = null;
int lastArrangedIndex = 0;
for (int i = 0; i < pathListBox.Items.Count; i++)
{
pathListBoxItem = (PathListBoxItem)pathListBox.ItemContainerGenerator.ContainerFromIndex(i);
if (pathListBoxItem != null && pathListBoxItem.LayoutPathIndex == layoutPathIndex)
{
if (lastItemArranged == null)
{
if (pathListBoxItem.IsArranged)
{
lastItemArranged = pathListBoxItem;
lastArrangedIndex = lastItemArranged.GlobalIndex;
}
}
else
{
if (pathListBoxItem.LocalIndex > lastItemArranged.LocalIndex &&
pathListBoxItem.Visibility == Visibility.Visible && pathListBoxItem.IsArranged)
{
lastItemArranged = pathListBoxItem;
lastArrangedIndex = lastItemArranged.GlobalIndex;
}
}
}
}
return(lastArrangedIndex);
}
private void AnimateStart(PathListBox pathListBox, int increment, int layoutPathIndex, int startItemIndex, Duration newDuration, bool isStoryboardInterruped)
{
LayoutPath layoutPath = pathListBox.LayoutPaths[layoutPathIndex];
if (layoutPath == null || increment == 0)
{
return;
}
// Get the distance between the two elements that are being arranged to compute the distance to animate start.
int itemCount = pathListBox.Items.Count;
int firstIndex = 0;
int nextIndex = 0;
firstIndex = PathListBoxExtensions.GetFirstArrangedIndex(pathListBox, layoutPathIndex);
nextIndex = (firstIndex + 1) % itemCount;
PathListBoxItem plbiStart = (PathListBoxItem)(pathListBox.ItemContainerGenerator.ContainerFromIndex(firstIndex));
PathListBoxItem plbiEnd = (PathListBoxItem)(pathListBox.ItemContainerGenerator.ContainerFromIndex(nextIndex));
if (plbiStart.IsArranged == false || plbiEnd.IsArranged == false)
{
if (pathListBox.WrapItems)
{
while (plbiStart.IsArranged == false || plbiEnd.IsArranged == false)
{
firstIndex = (firstIndex + 1) % itemCount;
nextIndex = (nextIndex + 1) % itemCount;
plbiStart = (PathListBoxItem)(pathListBox.ItemContainerGenerator.ContainerFromIndex(firstIndex));
plbiEnd = (PathListBoxItem)(pathListBox.ItemContainerGenerator.ContainerFromIndex(nextIndex));
}
}
else
{
return;
}
}
double startDx = 0;
if (plbiStart.LocalOffset > plbiEnd.LocalOffset)
{
// if the Start and End cross 0
startDx = increment * ((1 - plbiStart.LocalOffset) + plbiEnd.LocalOffset);
}
else
{
startDx = increment * (plbiEnd.LocalOffset - plbiStart.LocalOffset);
}
double startFrom = layoutPath.Start;
double startTo = layoutPath.Start;
PropertyPath propertyPath = new PropertyPath(String.Format("(ec:PathListBox.LayoutPaths)[{0}].(ec:LayoutPath.Start)", layoutPathIndex));
DoubleAnimation startPropertyAnimation = null;
if (isStoryboardInterruped)
{
// Find the DoubleAnimation that has already been created for this LayoutPath
for (int i = 0; i < this.startPropertyStoryboard.Children.Count; i++)
{
DoubleAnimation currentAnimation = (DoubleAnimation)this.startPropertyStoryboard.Children[i];
PropertyPath pp = Storyboard.GetTargetProperty(currentAnimation);
if (currentAnimation != null && String.Equals(pp.Path, propertyPath.Path))
{
startPropertyAnimation = currentAnimation;
break;
}
}
startTo = (double)startPropertyAnimation.To;
ShowItems();
startFrom = startTo;
}
else
{
startPropertyAnimation = new DoubleAnimation();
Storyboard.SetTarget(startPropertyAnimation, pathListBox);
Storyboard.SetTargetProperty(startPropertyAnimation, propertyPath);
this.startPropertyStoryboard.Children.Add(startPropertyAnimation);
}
startFrom += startDx;
int EnteringItemIndex = 0;
if (increment > 0)
{
EnteringItemIndex = pathListBox.GetLastArrangedIndex(layoutPathIndex);
EnteringItemIndex = (EnteringItemIndex + 1) % itemCount;
}
else
{
EnteringItemIndex = (pathListBox.GetFirstArrangedIndex(layoutPathIndex) - 1) % itemCount;
if (EnteringItemIndex < 0)
{
if (pathListBox.WrapItems)
{
EnteringItemIndex += itemCount;
}
}
}
PathListBoxItem pathListBoxItem = (PathListBoxItem)pathListBox.ItemContainerGenerator.ContainerFromIndex(EnteringItemIndex);
if (pathListBoxItem != null && this.HideEnteringItem)
{
this.enteringItem = pathListBoxItem;
this.enteringItem.Opacity = 0;
}
startPropertyAnimation.Duration = newDuration;
startPropertyAnimation.From = startFrom + 0.0001;
startPropertyAnimation.To = startTo;
startPropertyAnimation.EasingFunction = this.Ease;
}
