C# Add Widgets menu like in example with crated ASPxDockPanels in same file. (devExpress)

Question

i have a lot of ASPxDockPanels in my default.aspx.cs file. I'm creating on page loud like this.

Code

  ASPxDockPanel example = new ASPxDockPanel();
    example.ID = "Example";
    example.EncodeHtml = false;
    example.Styles.Header.Wrap = DevExpress.Utils.DefaultBoolean.True;
    example.HeaderText =  string.Format(@"<div class='container'>
        <h2 class='heading heading--l'>{0}</h2>
    </div>", exampleheadertext);

    example.ShowCloseButton = true;
    example.Controls.Add(divbody);
    example.OwnerZoneUID = "example";
    Page.Form.Controls.Add(example);

I have same dock panel about 7, i want make something like this example: https://demos.devexpress.com/ASPxDockAndPopupsDemos/Docking/Widgets.aspx

In this file all menu items creating in different files, and using a lot of aspx files. I need create menu bar in my default.aspx.cs because my panel functionality creating in here.

So my structure something like this.

In default.aspx i creating ASPxDockZone and in default.aspx.cs creating panel with example.OwnerZoneUID = "example";

<dxp:ASPxDockZone runat="server" ID="ASPxDockZone1" ZoneUID="example" CssClass="app__block"
    Width="100%" PanelSpacing="1">
</dxp:ASPxDockZone>

In conclusion I want make my panels with menu like in example (with img) in defoult.aspx.cs file using C#.

Thank you for your help.