// This method returns a bool to indicate if or not the panel layout is affected by this collection change
internal override bool OnItemsChangedInternal(object sender, ItemsChangedEventArgs args)
{
switch (args.Action)
{
case NotifyCollectionChangedAction.Add:
AddChildren(args.Position, args.ItemCount);
break;
case NotifyCollectionChangedAction.Remove:
RemoveChildren(args.Position, args.ItemUICount);
break;
case NotifyCollectionChangedAction.Replace:
ReplaceChildren(args.Position, args.ItemCount, args.ItemUICount);
break;
case NotifyCollectionChangedAction.Move:
MoveChildren(args.OldPosition, args.Position, args.ItemUICount);
break;
case NotifyCollectionChangedAction.Reset:
base.OnItemsChangedInternal(sender, args);
break;
}
return true;
}
private void ItemContainerGenerator_ItemsChanged(object sender, ItemsChangedEventArgs e)
{
if (e.Action == NotifyCollectionChangedAction.Add)
{
Friend addedFriend = (lstFriends.Items.Last() as Friend);
layers = new MapLayer();
overlay = new MapOverlay();
image = new BitmapImage();
image.UriSource = (new Uri(addedFriend.Picture, UriKind.Absolute));
brush = new ImageBrush();
brush.ImageSource = image;
ellipse = new Ellipse();
ellipse.DataContext = addedFriend;
ellipse.Hold += ellipse_Hold;
ellipse.Height = 100;
ellipse.Width = 100;
ellipse.Fill = brush;
overlay.GeoCoordinate = new GeoCoordinate(addedFriend.LastPosition.Latitude, addedFriend.LastPosition.Longitude);
overlay.Content = ellipse;
layers.Add(overlay);
myMap.Layers.Add(layers);
}
}
/// <summary>
/// Extends BeginInvoke so that when a state object is not needed, null does not need to be passed.
/// <example>
/// itemschangedeventhandler.BeginInvoke(sender, e, callback);
/// </example>
/// </summary>
public static IAsyncResult BeginInvoke(this ItemsChangedEventHandler itemschangedeventhandler, Object sender, ItemsChangedEventArgs e, AsyncCallback callback)
{
if(itemschangedeventhandler == null) throw new ArgumentNullException("itemschangedeventhandler");
return itemschangedeventhandler.BeginInvoke(sender, e, callback, null);
}
private void ItemContainerGenerator_ItemsChanged(object sender, System.Windows.Controls.Primitives.ItemsChangedEventArgs e)
{
_scrollViewer ??= VisualHelper.GetChild <ScrollViewer>(ListBoxChat);
_scrollViewer?.ScrollToBottom();
}
