How to Enable AddRemoveButton for ToolBarAdv

//Code Explains How to enable  AddRemoveButton in ToolbarAdv Control 
<Window
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
 xmlns:syncfusion="http://schemas.syncfusion.com/wpf"  x:Class="ToolBarAdv_IsOverFlowopen_EnableAddRemoveButton_.MainWindow"
 Title="MainWindow" Height="350" Width="525">
 <Grid>
<syncfusion:ToolBarTrayAdv Width="250" Grid.Column="2" VerticalAlignment="Center"  >
<syncfusion:ToolBarAdv Name="toolbar" Width="100" Height="50" Band="0"  EnableAddRemoveButton="True " IsOverflowOpen="True" VerticalAlignment="Bottom" >
<Button Height="20" syncfusion:ToolBarAdv.Label="NewFolder" >
 <Image Source="Fimages.jpg"  Width="20" Height="20"></Image>
</Button>
<Button Height="20" syncfusion:ToolBarAdv.Label="Document" >
<Image Source="images (1).png" Width="20" Height="20"></Image>
</Button>
<Button Height="20" syncfusion:ToolBarAdv.Label="Alignment" >
<Image Source="images.png" Width="20" Height="20"></Image>
</Button>
<Button Height="20" syncfusion:ToolBarAdv.Label="Download">
<Image Source="images2.jpg" Width="20" Height="20"></Image>
</Button>
 </syncfusion:ToolBarAdv>
<syncfusion:ToolBarAdv Width="100" Height="50" Band="1" BandIndex="100" EnableAddRemoveButton="True" IsOverflowOpen="True" >
<Button Height="20" syncfusion:ToolBarAdv.Label="NewFolder" >
<Image Source="document-open.png" Width="20" Height="20"></Image>
 </Button>
<Button Height="20" syncfusion:ToolBarAdv.Label="Document" >
<Image Source="images.png" Width="20" Height="20"></Image>
</Button>
<Button Height="20" syncfusion:ToolBarAdv.Label="Alignment" >
<Image Source="images (1).png" Width="20" Height="20"></Image>
</Button>
<Button Height="20" syncfusion:ToolBarAdv.Label="Download" >
<Image Source="images2.jpg" Width="20" Height="20"></Image>
 </Button>
</syncfusion:ToolBarAdv>
</syncfusion:ToolBarTrayAdv>
 </Grid>
</Window>

//Code Explains How to Enable EnableAddRemoveButton in ToolBar
namespace ToolBarAdv_IsOverFlowopen_EnableAddRemoveButton_
{
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
toolbar.EnableAddRemoveButton = true;
}
}
}