How to: Access the Document Manager

• Oct 17, 2023
• 3 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.

1. Create a new WindowController in the WinForms module’s Controllers folder.
2. 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.
3. Cast the MainForm Template by the IDocumentsHostWindow interface and access the Document Manager using the DocumentManager property.
4. Subscribe to the DocumentManager.ViewChanged event that occurs when the Document Manager has switched to another View.
5. 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.
6. Call the CustomizeDocumentManagerView method from both Frame.TemplateChanged and DocumentManager.ViewChanged event handlers.
7. Override the OnDeactivated method and unsubscribe from the Window.TemplateChanged event when the Controller is deactivated.

C#

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();
    }
}

VB.NET

Imports DevExpress.ExpressApp
Imports DevExpress.XtraBars.Docking2010
Imports DevExpress.XtraBars.Docking2010.Views
Imports DevExpress.XtraBars.Docking2010.Views.Tabbed
Imports DevExpress.ExpressApp.Templates
' ...
Public Class TabsCustomizationWindowController
    Inherits WindowController
    Public Sub New()
        TargetWindowType = WindowType.Main
    End Sub
    Protected Overrides Sub OnActivated()
        MyBase.OnActivated()
        AddHandler Window.TemplateChanged, AddressOf Window_TemplateChanged
    End Sub
    Private Sub Window_TemplateChanged(ByVal sender As Object, ByVal e As EventArgs)
        Dim template As IFrameTemplate = Window.Template
        Dim docManager As DocumentManager = CType(template, IDocumentsHostWindow).DocumentManager
        AddHandler docManager.ViewChanged, AddressOf docManager_ViewChanged
        CustomizeDocumentManagerView(docManager.View)
    End Sub
    Private Sub docManager_ViewChanged(ByVal sender As Object, ByVal args As ViewEventArgs)
        CustomizeDocumentManagerView(args.View)
    End Sub
    Private Shared Sub CustomizeDocumentManagerView(ByVal view As BaseView)
        If TypeOf view Is TabbedView Then
            CType(view, TabbedView).DocumentGroupProperties.HeaderLocation = _
            DevExpress.XtraTab.TabHeaderLocation.Left
            CType(view, TabbedView).DocumentGroupProperties.HeaderOrientation = _
            DevExpress.XtraTab.TabOrientation.Horizontal
        End If
    End Sub
    Protected Overrides Sub OnDeactivated()
        RemoveHandler Window.TemplateChanged, AddressOf Window_TemplateChanged
        MyBase.OnDeactivated()
    End Sub
End Class

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