public void StartViewChangeTo(SemanticZoomLocation source, SemanticZoomLocation destination)
{
//
}
public void CompleteViewChangeFrom(SemanticZoomLocation source, SemanticZoomLocation destination)
{
this.IsActiveView = false;
}
public void CompleteViewChangeTo(SemanticZoomLocation source, SemanticZoomLocation destination)
{
this.IsActiveView = true;
}
/// <summary>
/// Forces content in the view to scroll until the item specified by SemanticZoomLocation is visible. Also focuses that item if found.
/// </summary>
/// <param name="item">The item in the view to scroll to.</param>
public void MakeVisible(SemanticZoomLocation item)
{
//if (null != item.Item && !IsNavigating)
//this.SelectedItem = item.Item;
}
#pragma warning disable 1998 // considered for removal
async void ScrollTo(object group, object item, ScrollToPosition toPosition, bool shouldAnimate, bool includeGroup = false, bool previouslyFailed = false)
#pragma warning restore 1998
{
ScrollViewer viewer = GetScrollViewer();
if (viewer == null)
{
RoutedEventHandler loadedHandler = null;
loadedHandler = async(o, e) =>
{
List.Loaded -= loadedHandler;
// Here we try to avoid an exception, see explanation at bottom
await Dispatcher.RunIdleAsync(args => { ScrollTo(group, item, toPosition, shouldAnimate, includeGroup); });
};
List.Loaded += loadedHandler;
return;
}
var templatedItems = TemplatedItemsView.TemplatedItems;
Tuple <int, int> location = templatedItems.GetGroupAndIndexOfItem(group, item);
if (location.Item1 == -1 || location.Item2 == -1)
{
return;
}
object[] t = templatedItems.GetGroup(location.Item1).ItemsSource.Cast <object>().ToArray();
object c = t[location.Item2];
// scroll to desired item with animation
if (shouldAnimate && ScrollToItemWithAnimation(viewer, c))
{
return;
}
double viewportHeight = viewer.ViewportHeight;
var semanticLocation = new SemanticZoomLocation {
Item = c
};
switch (toPosition)
{
case ScrollToPosition.Start:
{
List.ScrollIntoView(c, ScrollIntoViewAlignment.Leading);
return;
}
case ScrollToPosition.MakeVisible:
{
List.ScrollIntoView(c, ScrollIntoViewAlignment.Default);
return;
}
case ScrollToPosition.End:
case ScrollToPosition.Center:
{
var content = (FrameworkElement)List.ItemTemplate.LoadContent();
content.DataContext = c;
content.Measure(new Windows.Foundation.Size(viewer.ActualWidth, double.PositiveInfinity));
double tHeight = content.DesiredSize.Height;
if (toPosition == ScrollToPosition.Center)
{
semanticLocation.Bounds = new Rect(0, viewportHeight / 2 - tHeight / 2, 0, 0);
}
else
{
semanticLocation.Bounds = new Rect(0, viewportHeight - tHeight, 0, 0);
}
break;
}
}
// Waiting for loaded doesn't seem to be enough anymore; the ScrollViewer does not appear until after Loaded.
// Even if the ScrollViewer is present, an invoke at low priority fails (E_FAIL) presumably because the items are
// still loading. An invoke at idle sometimes work, but isn't reliable enough, so we'll just have to commit
// treason and use a blanket catch for the E_FAIL and try again.
try
{
List.MakeVisible(semanticLocation);
}
catch (Exception)
{
if (previouslyFailed)
{
return;
}
Task.Delay(1).ContinueWith(ct => { ScrollTo(group, item, toPosition, shouldAnimate, includeGroup, true); }, TaskScheduler.FromCurrentSynchronizationContext()).WatchForError();
}
}
/// <summary>
/// Initializes item-wise operations related to a view change when the source view is a different view and the pending destination view is the implementing view.
/// </summary>
/// <param name="source">The view item as represented in the source view.</param>
/// <param name="destination">The view item as represented in the destination view.</param>
public void StartViewChangeTo(SemanticZoomLocation source, SemanticZoomLocation destination)
{
destination.Item = source.Item;
}
/// <summary>
/// Completes item-wise operations related to a view change when the implementing view is the destination view and the source view is a potentially different implementing view.
/// </summary>
/// <param name="source">The view item as represented in the source view.</param>
/// <param name="destination">The view item as represented in the destination view.</param>
public void CompleteViewChangeTo(SemanticZoomLocation source, SemanticZoomLocation destination)
{
}
public void MakeVisible(SemanticZoomLocation item)
{
}
public void StartViewChangeFrom(SemanticZoomLocation source, SemanticZoomLocation destination)
{
source.Item = this.dataGrid.GetDataView().Items.OfType <IDataGroup>().Select(c => c.Key);
}
/// <summary>
/// Completes item-wise operations related to a view change
/// when the implementing view is the destination view and the source view is a potentially
/// different implementing view.
/// </summary>
/// <param name="source">The view item as represented in the source view.</param>
/// <param name="destination">The view item as represented in the destination view.</param>
public void CompleteViewChangeTo(SemanticZoomLocation source, SemanticZoomLocation destination)
{
SelectedItem = source.Item;
Focus(Windows.UI.Xaml.FocusState.Programmatic);
}
public void CompleteViewChangeTo(SemanticZoomLocation source, SemanticZoomLocation destination)
{
// throw new NotImplementedException();
}
/// <summary>
/// Initializes item-wise operations related to a view change
/// when the implementing view is the source view and the pending
/// destination view is a potentially different implementing view.
/// </summary>
/// <param name="source">The view item as represented in the source view.</param>
/// <param name="destination">The view item as represented in the destination view.</param>
public void StartViewChangeFrom(SemanticZoomLocation source, SemanticZoomLocation destination)
{
destination.Item = SelectedItem;
}
public void CompleteViewChangeTo(SemanticZoomLocation source, SemanticZoomLocation destination)
{
Focus((FocusState)3);
}
public void StartViewChangeFrom(SemanticZoomLocation source, SemanticZoomLocation destination)
{
// Set the destination item to the currently selected item
destination.Item = this.SelectedItem;
}
public void StartViewChangeFrom(SemanticZoomLocation source, SemanticZoomLocation destination)
{
//throw new NotImplementedException();
}
public void MakeVisible(SemanticZoomLocation item)
{
//throw new NotImplementedException();
}
