uwp gridview item source not even executing

Question

I am using the new preview sdk 16190 of creators fall update as described in BUILD 2017.

I was binding a gridview in MVVM mode but it wasn't working so I simplified it to direct code behind to know the real problem and I even used a break point, it looks like the break point never gets a hit that line never executes so gridview item source remains empty.

Also I tried x:Bind on gridview item source, which doesn't work either. It's really frustrating because it doesn't make any sense. Below is my code

public VideoLibraryPage()
{
    InitializeComponent();
    VideoItems = new ObservableCollection<VideoItem>();
}
public ObservableCollection<VideoItem> VideoItems { get; set; }
protected async override void OnNavigatedTo(NavigationEventArgs e)
{
    var files = await KnownFolders.VideosLibrary.GetFilesAsync();
    foreach (var file in files)
    {
        var bit = new BitmapImage();
        bit.SetSource( await file.GetThumbnailAsync(ThumbnailMode.VideosView));
        //breakpoint on below line never gets hit, so not even a single item is added to VideItems collection.         
        VideoItems.Add(new VideoItem
        {
            Title = file.DisplayName,
            Display = bit
        });
    }
    VideosLibraryGridView.ItemsSource = VideoItems;
}

public class VideoItem
{
    public string Title { get; set; }
    public string Views { get; set; }
    public string Duration { get; set; }
    public ImageSource Display { get; set; }
    public StorageFile MyVideoFile { get; set; }
}

XAML

<controls:AdaptiveGridView Name="VideosLibraryGridView" Grid.Row="1"
                           Header="Videos"
                           Style="{StaticResource MainGridView}"
                           ItemClick="VideosLibraryGridView_ItemClicked"
                           >
        <controls:AdaptiveGridView.ItemTemplate>
            <DataTemplate  x:DataType="data:VideoItem">
                <StackPanel Margin="4" >
                    <Grid>
                        <Image  Source="{x:Bind Display, Mode=OneWay}" Style="{StaticResource GridViewImage}"/>
                        <Border Style="{StaticResource TimeBorder}">
                            <TextBlock Text="{x:Bind Duration, Mode=OneWay}" Foreground="White"/>
                        </Border>
                    </Grid>
                    <TextBlock Text="{x:Bind Title ,Mode=OneWay}"  Style="{StaticResource GridViewVideoName}"/>
                    <StackPanel Orientation="Horizontal" HorizontalAlignment="Stretch">
                        <TextBlock Text="{x:Bind Views, Mode=OneWay}" Style="{StaticResource GridViewViews}"/>
                        <TextBlock Text="Views" HorizontalAlignment="Right"/>
                    </StackPanel>
                </StackPanel>
            </DataTemplate>
        </controls:AdaptiveGridView.ItemTemplate>
    </controls:AdaptiveGridView>

Answer 1

the problem was only my RAM, the latest insiders SDK uses more RAM, and I had to restart my machine to clear the RAM and then it was working fine