VideoPlayerPage.xaml

<Page
    x:Class="UWPYouTubePlayer.VideoPlayerPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:UWPYouTubePlayer"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:themes="using:UWPYouTubePlayer.Themes"
    mc:Ignorable="d">

    <Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
        <MediaPlayerElement  Name="YoutubePlayer" MaxWidth="640" MaxHeight="360" AreTransportControlsEnabled="True">
            <MediaPlayerElement.TransportControls>
                <themes:CustomMediaTransportControls x:Name="CustomMediaControl" IsSkipBackwardButtonVisible="True" IsSkipForwardButtonVisible="True" IsSkipBackwardEnabled="True" IsSkipForwardEnabled="True" IsFullWindowButtonVisible="True" IsFullWindowEnabled="True" QualityChanged="CustomMediaControl_QualityChangedAsync"/>
            </MediaPlayerElement.TransportControls>
        </MediaPlayerElement>
    </Grid>
</Page>