Reading Image and Video from Device in Windows Phone 8.1

Reading Image and Video from device in windows phone 8.1:

MainPage.Xaml

<Button x:Name="btnPhotos" HorizontalAlignment="Left" Margin="2,256,0,0" VerticalAlignment="Top" FontFamily="Arial" Width="388" Height="96" Click="btnPhotos_Click">
    <TextBlock x:Name="textBlock" Text="Photos" FontSize="28" Foreground="#FF7A7070" Width="210" Height="42" />
</Button>
<Button x:Name="btnVideo" HorizontalAlignment="Left" Height="99" Margin="3,366,0,0" VerticalAlignment="Top" FontFamily="Arial" Width="387" Click="btnVideo_Click">
    <TextBlock Name="textVideo" Text="Video" FontSize="28" Margin="10,0,23,0" Foreground="#FF7A7070" Width="210" Height="42">
    </TextBlock>
</Button> <b>

MainPage.Xaml.cs

private async void btnPhotos_Click(object sender, RoutedEventArgs e)
{
    photosProgressBar.Visibility = Visibility.Visible;
    FileOpenPicker openPicker = new FileOpenPicker();
    openPicker.ViewMode = PickerViewMode.Thumbnail;
    openPicker.SuggestedStartLocation = PickerLocationId.PicturesLibrary;
    openPicker.FileTypeFilter.Add(".jpg");
    openPicker.FileTypeFilter.Add(".jpeg");
    openPicker.FileTypeFilter.Add(".png");
    openPicker.PickMultipleFilesAndContinue();
}
private async void btnVideo_Click(object sender, RoutedEventArgs e)
{
    videoProgressBar.Visibility = Visibility.Visible;
    FileOpenPicker openPicker = new FileOpenPicker();
    openPicker.ViewMode = PickerViewMode.Thumbnail;
    openPicker.SuggestedStartLocation = PickerLocationId.VideosLibrary;
    openPicker.FileTypeFilter.Add(".mp4");
    openPicker.PickMultipleFilesAndContinue();
}
public async void ContinueFileOpenPicker(FileOpenPickerContinuationEventArgs args)
{
    IReadOnlyList < StorageFile > files = args.Files;
    if (files.Count > 0)
    {
        foreach(var item in files)
        {
            //Do your work
        }
    }
}
< b >

App.Xaml.cs

protected override void OnActivated(IActivatedEventArgs args)
{
    // Sync osync = new Sync();
    var root = Window.Current.Content as Frame;
    var sync = root.Content as Sync;
    if (sync != null && args is FileOpenPickerContinuationEventArgs)
    {
        sync.ContinueFileOpenPicker(args as FileOpenPickerContinuationEventArgs);
    }
}