private bool isVisualStateExpanded(IExpanderDataItem item)
{
ContentControl contentWrapper = findItemContentWrapperOfItem(item);
bool expanded = contentWrapper.Content != null;
return(expanded);
}
private void collapseItem(IExpanderDataItem item)
{
//handle arrow rotation
//hide previous(rotaded) img
FrameworkElement prevImage = findItemElement(item, collapsedArrowComponentList);
prevImage.Visibility = Visibility.Collapsed;
FrameworkElement arrowComp = findItemElement(item, expandedArrowComponentList);;
arrowComp.Visibility = Visibility.Visible;
Visual xamlVisual = ElementCompositionPreview.GetElementVisual(arrowComp);
var compositor = xamlVisual.Compositor;
var animation = compositor.CreateScalarKeyFrameAnimation();
animation.Duration = TimeSpan.FromSeconds(1.0d);
animation.IterationCount = 1;
animation.InsertKeyFrame(0.0f, 0.0f);
float angle = -90.0f;//
animation.InsertKeyFrame(1.0f, angle);
xamlVisual.CenterPoint = new System.Numerics.Vector3(5.0f, 5.0f, 0);
//animation.StopBehavior = AnimationStopBehavior.SetToFinalValue;
xamlVisual.StartAnimation("RotationAngleInDegrees", animation);
// hide item content
ContentControl contentWrapper = findItemContentWrapperOfItem(item);
((UIElement)contentWrapper.Content).Visibility = Visibility.Collapsed;
contentWrapper.Content = null;
}
private FrameworkElement findItemElement(IExpanderDataItem item, List <FrameworkElement> elementsList)
{
FrameworkElement elem = null;
foreach (FrameworkElement fe in elementsList)
{
if (item.Equals(fe.DataContext))
{
elem = fe;
break;
}
}
return(elem);
}
private ContentControl findItemContentWrapperOfItem(IExpanderDataItem item)
{
ContentControl elem = null;
foreach (ContentControl fe in itemContentWrappersList)
{
if (item.Equals(fe.DataContext))
{
elem = fe;
break;
}
}
return(elem);
}
