FlyplayerView.xaml

<Window x:Class="PlayerDemo.FlyplayerView"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:fl="clr-namespace:FlyleafLib.Controls.WPF;assembly=FlyleafLib"
        xmlns:local="clr-namespace:PlayerDemo"
        mc:Ignorable="d"
        Background="Green"
        Title="FlyplayerView" Height="450" Width="800">
    <fl:FlyleafHost>
            <!--<Grid Background="Red">
                <Grid VerticalAlignment="Top">
                    <Slider Value="100"/>
                </Grid>
                <Grid VerticalAlignment="Center">
                    <Slider Value="100"/>
                </Grid>
                <Grid VerticalAlignment="Bottom" Margin="0 0 0 0">
                    <Slider Value="100"/>
                </Grid>
            </Grid>-->
        <Slider VerticalAlignment="Bottom" Value="100" Background="Red"/>
    </fl:FlyleafHost>
</Window>