EditorWithText editor = new EditorWithText();
this.dayView.AppointmentEditor = editor;
editor.AfterEnterEditMode += new EventHandler(this.editor_AfterEnterEditMode);
editor.BeforeExitEditMode += new BeforeExitEditModeEventHandler(editor_BeforeExitEditMode);

private void editor_AfterEnterEditMode(object sender, EventArgs e)
{
    ContextMenu contextMenu = new ContextMenu();
    contextMenu.MenuItems.Add( "One" );
    contextMenu.MenuItems.Add( "Two" );
    contextMenu.MenuItems.Add( "Three" );

    this.dayView.Controls[0].ContextMenu = contextMenu;
}

private void editor_BeforeExitEditMode(object sender, BeforeExitEditModeEventArgs e)
{
    //  TODO: Clean up context menu
}