<Window x:Class="WPFPopup.RuntimePopup"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="RuntimePopup" Height="800" Width="800" Loaded="Window_Loaded">
    <StackPanel>
        <Button Height="300">T</Button>
        <Grid>
            <Grid.ColumnDefinitions>
                <ColumnDefinition/>
                <ColumnDefinition/>
            </Grid.ColumnDefinitions>
            <CheckBox Name="PCheckBox" Width="100" Margin="60,10,0,0"
              Content="Popup Window"/>
            <CheckBox Name="PCheckBox2" Grid.Column="1" Width="100" Margin="0,10,0,0"
              Content="Popup Window"/>
        </Grid>
       
        <Button HorizontalAlignment="Left" Width="169" Margin="10,10,0,0">
            <Button.Triggers>
                <EventTrigger RoutedEvent="Button.Click">
                    <BeginStoryboard>
                        <Storyboard>
                            <DoubleAnimation 
                Storyboard.TargetName="theTransform"
                Storyboard.TargetProperty="(RotateTransform.Angle)" 
                From="0" To="360" Duration="0:0:5" AutoReverse="True"/>
                        </Storyboard>
                    </BeginStoryboard>
                </EventTrigger>
            </Button.Triggers>
            Start Animation
        </Button>
        <Popup x:Name="popusBottom" IsOpen="{Binding ElementName=PCheckBox,Path=IsChecked}" 
           PlacementTarget="{Binding ElementName=PCheckBox}"            
           AllowsTransparency="True"
           PopupAnimation="Fade"
           HorizontalOffset="5"
           VerticalOffset="-120"  
              
           >    
            <Canvas  Margin="150" Background="Green">
                <Canvas.RenderTransform>
                    <RotateTransform x:Name="theTransform" />
                </Canvas.RenderTransform>
                <WrapPanel >
                    <WrapPanel.Background>
                        <ImageBrush ImageSource="BG.png"/>
                    </WrapPanel.Background>
                     <Button Click="Button_Click" Margin="15">Test</Button>
                    <ListBox Height="90" Margin="15">
                        <ListBoxItem>Item1</ListBoxItem>
                        <ListBoxItem>Item2</ListBoxItem>
                        <ListBoxItem>Item3</ListBoxItem>
                        <ListBoxItem>Item1</ListBoxItem>
                        <ListBoxItem>Item2</ListBoxItem>
                        <ListBoxItem>Item3</ListBoxItem>
                        <ListBoxItem>Item1</ListBoxItem>
                        <ListBoxItem>Item2</ListBoxItem>
                        <ListBoxItem>Item3</ListBoxItem>
                    </ListBox>
                </WrapPanel>
               
            </Canvas>
        </Popup>
        <Popup x:Name="popusBottom2" IsOpen="{Binding ElementName=PCheckBox2,Path=IsChecked}" 
           PlacementTarget="{Binding ElementName=PCheckBox2}"            
           AllowsTransparency="True"
           PopupAnimation="Fade"
           HorizontalOffset="5"
           VerticalOffset="-120"                   
           >
            <Canvas Margin="150">
                <WrapPanel >
                    <WrapPanel.Background>
                        <ImageBrush   ImageSource="BG.png"/>
                    </WrapPanel.Background>
                    <Button Click="Button_Click" Margin="15">Test</Button>
                    <ListBox Height="90" Margin="15">
                        <ListBoxItem>Item1</ListBoxItem>
                        <ListBoxItem>Item2</ListBoxItem>
                        <ListBoxItem>Item3</ListBoxItem>
                        <ListBoxItem>Item1</ListBoxItem>
                        <ListBoxItem>Item2</ListBoxItem>
                        <ListBoxItem>Item3</ListBoxItem>
                        <ListBoxItem>Item1</ListBoxItem>
                        <ListBoxItem>Item2</ListBoxItem>
                        <ListBoxItem>Item3</ListBoxItem>
                    </ListBox>
                </WrapPanel>

            </Canvas>
        </Popup>
    </StackPanel>

</Window>

  

C# code

 public partial class RuntimePopup : Window
    {
        public RuntimePopup()
        {
            InitializeComponent();
            LocationChanged += new EventHandler(RuntimePopup_LocationChanged);
        }

        void RuntimePopup_LocationChanged(object sender, EventArgs e)
        {
            var mi = typeof(Popup).GetMethod("UpdatePosition", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
            mi.Invoke(popusBottom, null);
        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            MessageBox.Show("Test");
        }
    }