// TODO: this API should go on UIElement.
internal void StartBringIntoView(UIElement element, double alignmentX, double alignmentY, double offsetX, double offsetY, bool animate)
{
m_pendingBringIntoView = new BringIntoViewState(
element,
alignmentX,
alignmentY,
offsetX,
offsetY,
animate);
}
/// <summary>
/// Makes sure the target is visible in the client area. May cause navigation
/// to a different page.
/// </summary>
/// <param name="args">RequestBringIntoViewEventArgs indicates the element and region to scroll into view.</param>
private void HandleRequestBringIntoView(RequestBringIntoViewEventArgs args)
{
DependencyObject child;
DependencyObject parent;
ContentPosition contentPosition;
BringIntoViewState bringIntoViewState;
DynamicDocumentPaginator documentPaginator;
Rect targetRect = Rect.Empty;
if (args != null && args.TargetObject != null && _document is DependencyObject)
{
// If the passed in object is a logical child of DocumentViewer's Document,
// attempt to make it visible now.
// Special case: TargetObject is the document itself. Then scroll to the top (page 1).
// This supports navigating from baseURI#anchor to just baseURI.
parent = _document as DependencyObject;
if (args.TargetObject == _document)
{
OnGoToPageCommand(1);
args.Handled = true; // Mark the event as handled.
}
else
{
// Verify if TargetObject is in fact a child of Document.
child = args.TargetObject;
while (child != null && child != parent)
{
// Skip elements in the control's template (if such exists) and
// walk up logical tree to find if the focused element is within
// the document.
FrameworkElement fe = child as FrameworkElement;
if (fe != null && fe.TemplatedParent != null)
{
child = fe.TemplatedParent;
}
else
{
child = LogicalTreeHelper.GetParent(child);
}
}
if (child != null)
{
// Special case UIElements already connected to visual tree.
if (args.TargetObject is UIElement)
{
UIElement targetObject = (UIElement)args.TargetObject;
if (VisualTreeHelper.IsAncestorOf(this, targetObject))
{
targetRect = args.TargetRect;
if (targetRect.IsEmpty)
{
targetRect = new Rect(targetObject.RenderSize);
}
GeneralTransform transform = targetObject.TransformToAncestor(this);
targetRect = transform.TransformBounds(targetRect);
targetRect.IntersectsWith(new Rect(this.RenderSize));
}
}
// If target is not already visible, bring appropriate page into view.
if (targetRect.IsEmpty)
{
// Get content position for given target.
documentPaginator = _document.DocumentPaginator as DynamicDocumentPaginator;
if (documentPaginator != null)
{
contentPosition = documentPaginator.GetObjectPosition(args.TargetObject);
if (contentPosition != null && contentPosition != ContentPosition.Missing)
{
// Asynchronously retrieve PageNumber for given ContentPosition.
bringIntoViewState = new BringIntoViewState(this, contentPosition, args.TargetObject, args.TargetRect);
documentPaginator.GetPageNumberAsync(contentPosition, bringIntoViewState);
}
}
}
args.Handled = true; // Mark the event as handled.
}
}
if (args.Handled)
{
// Create new BringIntoView request for this element, so
// if there is an ancestor handling BringIntoView, it can
// react appropriately and bring this element into view.
if (targetRect.IsEmpty)
{
BringIntoView();
}
else
{
BringIntoView(targetRect);
}
}
}
}
public ItemsRepeaterScrollHost()
{
m_pendingBringIntoView = new BringIntoViewState(this);
}
