How to: Access the Document Manager

Feb 20, 2026
2 minutes to read

This topic demonstrates how to access the Document Manager that the MdiShowViewStrategy uses to show Views in a WinForms application. You will locate tab captions to the left and orient them horizontally.

Here, it is assumed that you have the UI type set to TabbedMDI in the Model Editor for your Windows Forms application (see IModelOptionsWin.UIType). Perform the following steps to access the DocumentManager object and customize its default settings.

Create a new WindowController in the WinForms module’s Controllers folder.
The Document Manager is located on the MainForm Template. Override the Controller’s OnActivated method and subscribe to the main Window’s Frame.TemplateChanged event to access the MainForm Template after it has been created or changed.
Cast the MainForm Template by the IDocumentsHostWindow interface and access the Document Manager using the DocumentManager property.
Subscribe to the DocumentManager.ViewChanged event that occurs when the Document Manager has switched to another View.
Add the following CustomizeDocumentManagerView method that changes the location and orientation of tab captions if the Document Manager’s View is of the TabbedView type.
Call the CustomizeDocumentManagerView method from both Frame.TemplateChanged and DocumentManager.ViewChanged event handlers.
Override the OnDeactivated method and unsubscribe from the Window.TemplateChanged event when the Controller is deactivated.

csharp

using DevExpress.ExpressApp;
using DevExpress.XtraBars.Docking2010;
using DevExpress.XtraBars.Docking2010.Views;
using DevExpress.XtraBars.Docking2010.Views.Tabbed;
using DevExpress.ExpressApp.Templates;
// ...
public class TabsCustomizationWindowController : WindowController {
    public TabsCustomizationWindowController() {
        TargetWindowType = WindowType.Main;
    }
    protected override void OnActivated() {
        base.OnActivated();
        Window.TemplateChanged += Window_TemplateChanged;
    }
    private void Window_TemplateChanged(object sender, EventArgs e) {
        IFrameTemplate template = Window.Template;
        DocumentManager docManager = ((IDocumentsHostWindow)template).DocumentManager;
        docManager.ViewChanged += docManager_ViewChanged;
        CustomizeDocumentManagerView(docManager.View);
    }
    private void docManager_ViewChanged(object sender, ViewEventArgs args) {
        CustomizeDocumentManagerView(args.View);
    }
    private static void CustomizeDocumentManagerView(BaseView view) {
        if(view is TabbedView) {
            ((TabbedView)view).DocumentGroupProperties.HeaderLocation = 
                DevExpress.XtraTab.TabHeaderLocation.Left;
            ((TabbedView)view).DocumentGroupProperties.HeaderOrientation = 
                DevExpress.XtraTab.TabOrientation.Horizontal;
        }
    }
    protected override void OnDeactivated() {
        Window.TemplateChanged -= Window_TemplateChanged;
        base.OnDeactivated();
    }
}

Run the application to ensure that the tab captions location is changed.