[ComVisible(false)]
[DXLicenseWinForms]
public class AppointmentStatusEdit :
    ImageComboBoxEdit

<ComVisible(False)>
<DXLicenseWinForms>
Public Class AppointmentStatusEdit
    Inherits ImageComboBoxEdit

using DevExpress.XtraScheduler;
using DevExpress.XtraScheduler.UI;
// ...

public partial class AppointmentForm : Form
    {
    SchedulerControl control;
    SchedulerStorage storage;
    AppointmentFormController controller;

    public AppointmentForm(SchedulerControl control, Appointment apt)
    {
    // The appointment editing should be performed 
    // via the AppointmentFormController instance.
            this.controller = CreateController(control, apt);

            InitializeComponent();

            this.control = control;
            this.storage = control.Storage;

            UpdateForm();
        }

        protected virtual AppointmentFormController 
            CreateController(SchedulerControl control, Appointment apt)
        {
            return new AppointmentFormController(control, apt);
        }

        // Fill in the controls with initial values.
        protected virtual void UpdateForm()
        {
            edtStatus.Storage = storage;
            edtStatus.Status = controller.GetStatus();

            edtResources.Storage = control.Storage;
            edtResources.ResourceId = controller.ResourceId;

            edtLabel.Storage = storage;
            edtLabel.Label = controller.GetLabel();

            // We can change resources only for base appointments.
            edtResources.Enabled = controller.CanEditResource;
        }

       // User actions are tracked by the controller.
       private void edtLabel_EditValueChanged(object sender, EventArgs e)
        {
            controller.SetLabel(edtLabel.Label);
        }

        private void edtResources_EditValueChanged(object sender, EventArgs e)
        {
            controller.ResourceId = edtResources.ResourceId;
        }

        private void edtStatus_SelectedIndexChanged(object sender, EventArgs e)
        {
            controller.SetStatus(edtStatus.Status);
        }

        // Confirm the changes and write them back.
        private void btnOk_Click(object sender, EventArgs e)
        {
            controller.ApplyChanges();
            this.DialogResult = Windows.Forms.DialogResult.OK;
        }

    }

Imports DevExpress.XtraScheduler
Imports DevExpress.XtraScheduler.UI
' ...

Public Class AppointmentForm
    Inherits Form
    Private control As SchedulerControl
    Private storage As SchedulerStorage
    Private controller As AppointmentFormController

    Public Sub New(ByVal control As SchedulerControl, ByVal apt As Appointment)
        MyBase.New()

        ' The appointment editing should be performed 
        ' via the AppointmentFormController instance.
        Me.controller = CreateController(control, apt)
        InitializeComponent()
        Me.control = control
        Me.storage = control.Storage
        UpdateForm()
    End Sub

    Protected Overridable Function CreateController(ByVal control As SchedulerControl, _
        ByVal apt As Appointment) As AppointmentFormController

        Return New AppointmentFormController(control, apt)
    End Function

    ' Fill in the controls with initial values.
    Protected Overridable Sub UpdateForm()
        edtStatus.Storage = storage
        edtStatus.Status = controller.GetStatus
        edtResources.Storage = control.Storage
        edtResources.ResourceId = controller.ResourceId
        edtLabel.Storage = storage
        edtLabel.Label = controller.GetLabel
        'We can change resources only for base appointments.
        edtResources.Enabled = controller.CanEditResource
    End Sub

    ' User actions are tracked by the controller.
    Private Sub edtLabel_EditValueChanged(ByVal sender As Object, _
        ByVal e As EventArgs) Handles edtLabel.EditValueChanged

        controller.SetLabel(edtLabel.Label)
    End Sub

    Private Sub edtResources_EditValueChanged(ByVal sender As Object, _
        ByVal e As EventArgs) Handles edtResources.EditValueChanged

        controller.ResourceId = edtResources.ResourceId
    End Sub

    Private Sub edtStatus_SelectedIndexChanged(ByVal sender As Object, _
        ByVal e As EventArgs) Handles edtStatus.EditValueChanged

        controller.SetStatus(edtStatus.Status)
    End Sub

    ' Confirm the changes and write them back.
    Private Sub btnOk_Click(ByVal sender As Object, _
        ByVal e As EventArgs) Handles btnOk.Click
        controller.ApplyChanges()
        Me.DialogResult = Windows.Forms.DialogResult.OK
    End Sub
End Class