类型未定义错误 - 设计视图 - vb.net

Question

提前道歉。我一直都在努力探索命名空间，类，方法，参考，库等。

我已将下面的代码保存为项目中的类和单独文件。它基本上允许您在ContextMenus上包含Slider控件。我可以通过Designer在现有表单上包含这个新控件没问题。

Imports System.Windows.Forms.Design

<ToolStripItemDesignerAvailability(ToolStripItemDesignerAvailability.ContextMenuStrip), DebuggerStepThrough()>
Public Class TrackBarMenuItem
    Inherits ToolStripControlHost

    Public Sub New()
        MyBase.New(New TrackBar())
    End Sub

    Public ReadOnly Property TrackbarControl() As TrackBar
        Get
            Return CType(Control, TrackBar)
        End Get
    End Property

    ' PROPERTIES
    ' Add properties, events etc. you want to expose...

    Public Property Value() As Integer
        Get
            Return TrackbarControl.Value
        End Get
        Set(value As Integer)
            TrackbarControl.Value = value
        End Set
    End Property

    Public Property Minimum() As Integer
        Get
            Return TrackbarControl.Minimum
        End Get
        Set(value As Integer)
            TrackbarControl.Minimum = value
        End Set
    End Property

    Public Property Maximum() As Integer
        Get
            Return TrackbarControl.Maximum
        End Get
        Set(value As Integer)
            TrackbarControl.Maximum = value
        End Set
    End Property

    Public Property LargeChange() As Integer
        Get
            Return TrackbarControl.LargeChange
        End Get
        Set(value As Integer)
            TrackbarControl.LargeChange = value
        End Set
    End Property

    Public Property SmallChange() As Integer
        Get
            Return TrackbarControl.SmallChange
        End Get
        Set(value As Integer)
            TrackbarControl.SmallChange = value
        End Set
    End Property

    Public Property Orientation() As Integer
        Get
            Return TrackbarControl.Orientation
        End Get
        Set(value As Integer)
            TrackbarControl.Orientation = value
        End Set
    End Property

    Public Property TickFrequency() As Integer
        Get
            Return TrackbarControl.TickFrequency
        End Get
        Set(value As Integer)
            TrackbarControl.TickFrequency = value
        End Set
    End Property

    Public Property TickStyle() As Integer
        Get
            Return TrackbarControl.TickStyle
        End Get
        Set(value As Integer)
            TrackbarControl.TickStyle = value
        End Set
    End Property

    'EVENTS:
    Protected Overrides Sub OnSubscribeControlEvents(ByVal c As Control)
        ' Call the base so the base events are connected. 
        MyBase.OnSubscribeControlEvents(c)
        ' Cast the control to a Taskbar control. 
        Dim trackbarcontrol As TrackBar = CType(c, TrackBar)
        ' Add the events: 
        AddHandler trackbarcontrol.ValueChanged, AddressOf HandleValueChanged
        'AddHandler trackbarcontrol.Scroll, AddressOf HandleScroll
    End Sub

    ' Slider changed event
    Public Event SliderValueChanged As EventHandler
    Private Sub HandleValueChanged(ByVal sender As Object, ByVal e As EventArgs)
        RaiseEvent SliderValueChanged(Me, e)
    End Sub

    Protected Overrides Sub OnUnsubscribeControlEvents(ByVal c As Control)
        ' Call the base method so the basic events are unsubscribed. 
        MyBase.OnUnsubscribeControlEvents(c)
        ' Cast the control to a MonthCalendar control. 
        Dim monthCalendarControl As MonthCalendar = _
            CType(c, MonthCalendar)
        ' Remove the event. 
        RemoveHandler TrackbarControl.ValueChanged, AddressOf HandleValueChanged
    End Sub

End Class

但是，在编译完整代码之前会出现错误，如下所示：

Error   5   Type 'CPWBAdmin.TrackBarMenuItem' is not defined.   C:\Users\Steve\Documents\Visual Studio 2013\Projects\CPWBAdmin\CPWBAdmin\MarqueeEditor.Designer.vb  208 34  CPWBAdmin

在设计师视图中，一个冒犯文章的例子：

  Me._ImgBrightnessSlider = New CPWBAdmin.TrackBarMenuItem()

如果我将其更改为：

  Me._ImgBrightnessSlider = New Global.CPWBAdmin.TrackBarMenuItem()

然后它编译并运行正常。 直到下次我编辑控件时，错误会再次出现。

阅读，可能与类名称相关＆＃39;匹配命名空间＆＃39; - 但我不知道如何确定这个类的命名空间（文件名？）。

当然这是很多专业人士的基础，所以任何业余爱好者的帮助都会受到赞赏！