private void ScrollingHost_ViewChanged(object sender, ScrollViewerViewChangedEventArgs e)
{
var scrollingHost = Stickers.ItemsPanelRoot as ItemsWrapGrid;
if (scrollingHost != null && Pivot.SelectedIndex == 2)
{
var first = Stickers.ContainerFromIndex(scrollingHost.FirstVisibleIndex);
if (first != null)
{
var header = Stickers.GroupHeaderContainerFromItemContainer(first) as GridViewHeaderItem;
if (header != null && header != Toolbar.SelectedItem)
{
Toolbar.SelectedItem = header.Content;
Toolbar.ScrollIntoView(header.Content);
}
}
}
}
private async void LoadVisibleStickers()
{
var scrollingHost = Stickers.ItemsPanelRoot as ItemsWrapGrid;
if (scrollingHost == null)
{
return;
}
if (scrollingHost.FirstVisibleIndex < 0)
{
return;
}
var lastSet = 0L;
for (int i = scrollingHost.FirstVisibleIndex; i <= scrollingHost.LastVisibleIndex; i++)
{
if (i >= Stickers.Items.Count)
{
return;
}
var first = Stickers.Items[i] as ViewModels.Dialogs.StickerViewModel;
if (first == null || first.SetId == lastSet)
{
continue;
}
lastSet = first.SetId;
var fromItem = Stickers.ContainerFromItem(first);
if (fromItem == null)
{
continue;
}
var header = Stickers.GroupHeaderContainerFromItemContainer(fromItem) as GridViewHeaderItem;
if (header == null)
{
continue;
}
var group = header.Content as ViewModels.Dialogs.StickerSetViewModel;
if (group == null || group.IsLoaded)
{
continue;
}
group.IsLoaded = true;
Debug.WriteLine("Loading sticker set " + group.Id);
var response = await ViewModel.ProtoService.SendAsync(new GetStickerSet(group.Id));
if (response is StickerSet full)
{
group.Update(full);
//group.Stickers.RaiseCollectionChanged(new System.Collections.Specialized.NotifyCollectionChangedEventArgs(System.Collections.Specialized.NotifyCollectionChangedAction.Reset));
int j = 0;
foreach (var sticker in group.Stickers)
{
if (sticker.Thumbnail == null)
{
continue;
}
//group.Stickers.RaiseCollectionChanged(new System.Collections.Specialized.NotifyCollectionChangedEventArgs(System.Collections.Specialized.NotifyCollectionChangedAction.Move, sticker, j, j));
//j++;
var container = Stickers.ContainerFromItem(sticker) as SelectorItem;
if (container == null)
{
continue;
}
var content = container.ContentTemplateRoot as Image;
var file = sticker.Thumbnail.Photo;
if (file.Local.IsDownloadingCompleted)
{
var temp = await StorageFile.GetFileFromPathAsync(file.Local.Path);
var buffer = await FileIO.ReadBufferAsync(temp);
content.Source = WebPImage.DecodeFromBuffer(buffer);
}
else if (file.Local.CanBeDownloaded && !file.Local.IsDownloadingActive)
{
DownloadFile(file.Id, sticker);
}
}
}
}
}
