/// <summary>
/// <see cref="ITextView.BringPositionIntoViewAsync"/>
/// </summary>
internal override void BringPositionIntoViewAsync(ITextPointer position, object userState)
{
DocumentPageTextView pageTextView;
int pageNumber;
BringPositionIntoViewRequest pendingRequest;
// Verify that layout information is valid. Cannot continue if not valid.
if (!IsValid)
{
throw new InvalidOperationException(SR.Get(SRID.TextViewInvalidLayout));
}
if (_pendingRequest != null)
{
// Ignore new request if the previous is not completed yet.
OnBringPositionIntoViewCompleted(new BringPositionIntoViewCompletedEventArgs(
position, false, null, false, userState));
}
pendingRequest = new BringPositionIntoViewRequest(position, userState);
_pendingRequest = pendingRequest;
pageTextView = GetTextViewFromPosition(position);
// If the position is currently in the view, do nothing.
// Otherwise, let the viewer handle the request.
if (pageTextView != null)
{
pendingRequest.Succeeded = true;
OnBringPositionIntoViewCompleted(pendingRequest);
}
else
{
if (position is ContentPosition)
{
DynamicDocumentPaginator documentPaginator = _viewer.Document.DocumentPaginator as DynamicDocumentPaginator;
if (documentPaginator != null)
{
pageNumber = documentPaginator.GetPageNumber((ContentPosition)position) + 1;
if (_viewer.CanGoToPage(pageNumber))
{
_viewer.GoToPage(pageNumber);
}
else
{
OnBringPositionIntoViewCompleted(pendingRequest);
}
}
else
{
OnBringPositionIntoViewCompleted(pendingRequest);
}
}
else
{
OnBringPositionIntoViewCompleted(pendingRequest);
}
}
}
/// <summary>
/// Fires BringPositionIntoViewCompleted event.
/// </summary>
private void OnBringPositionIntoViewCompleted(BringPositionIntoViewRequest request)
{
_pendingRequest = null;
OnBringPositionIntoViewCompleted(new BringPositionIntoViewCompletedEventArgs(
request.Position, request.Succeeded, null, false, request.UserState));
}
