在在设计时用户控件集合编辑器 [英] Collection Editor within a User Control at Design Time

问题描述

我有一个Windows应用程序项目中的用户控件类。其中它的性质是我定义的另一个类的集合。我似乎无法找到如何得到标准的集合编辑器在设计时为它工作一个很好的例子。

I have a UserControl class in a Windows Application project. One of the properties of it is a collection of another class that I have defined. I can't seem to find a good example of how to get the standard collection editor working for it at design time.

我得到它的工作使用一些例如code，我发现到一定程度，但在我的收藏中的数据不会被保存。当我退出的形式，并在设计时打开它备份的数据是不存在了。

I got it working using some example code I found to a degree, but the data in my collection doesn't get saved. When I exit the form and open it back up in design time the data isn't there any more.

下面是我的类：

Public Class Gauge
Inherits Control

Private WithEvents _Captions As New CaptionCollection

<Category("Gauge"), _
TypeConverter(GetType(CaptionCollectionConverter)), _
Description("Custom text displayed on the gauge.")> _
Public Property Captions() As CaptionCollection
	Get
		Return _Captions
	End Get
	Set(ByVal value As CaptionCollection)
		_Captions = value
	End Set
End Property

<Category("Gauge"), _
TypeConverter(GetType(CaptionConverter)), _
Description("Custom text displayed on the gauge.")> _
Public Class Caption
	Private _Text As String = ""
	Private _Color As Color = Color.Black
	Private _TextIsValue As Boolean
	Private _Position As New Point(0, 0)

	Public Property Text() As String
		Get
			Return _Text
		End Get
		Set(ByVal value As String)
			If _Text <> value Then
				_Text = value
			End If
		End Set
	End Property

	Public Property Color() As Color
		Get
			Return _Color
		End Get
		Set(ByVal value As Color)
			If _Color <> value Then
				_Color = value
			End If
		End Set
	End Property

	Public Property TextIsValue() As Boolean
		Get
			Return _TextIsValue
		End Get
		Set(ByVal value As Boolean)
			If _TextIsValue <> value Then
				_TextIsValue = value
			End If
		End Set
	End Property

	Public Property Position() As Point
		Get
			Return _Position
		End Get
		Set(ByVal value As Point)
			If _Position <> value Then
				_Position = value
			End If
		End Set
	End Property
End Class

Public Class CaptionCollection
	Inherits CollectionBase
	Implements ICustomTypeDescriptor

	Public Sub Add(ByVal c As Caption)
		Me.List.Add(c)
	End Sub

	Public Sub Remove(ByVal c As Caption)
		Me.List.Remove(c)
	End Sub

	Default Public ReadOnly Property Item(ByVal index As Integer) As Caption
		Get
			Return DirectCast(Me.List(index), Caption)
		End Get
	End Property

	' Implementation of interface ICustomTypeDescriptor 
	Public Function GetClassName() As String Implements System.ComponentModel.ICustomTypeDescriptor.GetClassName
		Return TypeDescriptor.GetClassName(Me, True)
	End Function

	Public Function GetAttributes() As AttributeCollection Implements System.ComponentModel.ICustomTypeDescriptor.GetAttributes
		Return TypeDescriptor.GetAttributes(Me, True)
	End Function

	Public Function GetComponentName() As String Implements System.ComponentModel.ICustomTypeDescriptor.GetComponentName
		Return TypeDescriptor.GetComponentName(Me, True)
	End Function

	Public Function GetConverter() As TypeConverter Implements System.ComponentModel.ICustomTypeDescriptor.GetConverter
		Return TypeDescriptor.GetConverter(Me, True)
	End Function

	Public Function GetDefaultEvent() As EventDescriptor Implements System.ComponentModel.ICustomTypeDescriptor.GetDefaultEvent
		Return TypeDescriptor.GetDefaultEvent(Me, True)
	End Function

	Public Function GetDefaultProperty() As PropertyDescriptor Implements System.ComponentModel.ICustomTypeDescriptor.GetDefaultProperty
		Return TypeDescriptor.GetDefaultProperty(Me, True)
	End Function

	Public Function GetEditor(ByVal editorBaseType As Type) As Object Implements System.ComponentModel.ICustomTypeDescriptor.GetEditor
		Return TypeDescriptor.GetEditor(Me, editorBaseType, True)
	End Function

	Public Function GetEvents(ByVal attributes As Attribute()) As EventDescriptorCollection Implements System.ComponentModel.ICustomTypeDescriptor.GetEvents
		Return TypeDescriptor.GetEvents(Me, attributes, True)
	End Function

	Public Function GetEvents() As EventDescriptorCollection Implements System.ComponentModel.ICustomTypeDescriptor.GetEvents
		Return TypeDescriptor.GetEvents(Me, True)
	End Function

	Public Function GetPropertyOwner(ByVal pd As PropertyDescriptor) As Object Implements System.ComponentModel.ICustomTypeDescriptor.GetPropertyOwner
		Return Me
	End Function

	Public Function GetProperties(ByVal attributes As Attribute()) As PropertyDescriptorCollection Implements System.ComponentModel.ICustomTypeDescriptor.GetProperties
		Return GetProperties()
	End Function

	Public Function GetProperties() As PropertyDescriptorCollection Implements System.ComponentModel.ICustomTypeDescriptor.GetProperties
		' Create a collection object to hold property descriptors
		Dim pds As New PropertyDescriptorCollection(Nothing)

		' Iterate the list of employees
		For i As Integer = 0 To Me.List.Count - 1
			' Create a property descriptor for the caption item and add to the property descriptor collection
			Dim pd As New CaptionCollectionPropertyDescriptor(Me, i)
			pds.Add(pd)
		Next
		' return the property descriptor collection
		Return pds
	End Function
End Class

' This is a special type converter which will be associated with the Caption class.
' It converts a Caption object to string representation for use in a property grid.
Friend Class CaptionConverter
	Inherits ExpandableObjectConverter

	Public Overloads Overrides Function ConvertTo(ByVal context As ITypeDescriptorContext, ByVal culture As System.Globalization.CultureInfo, ByVal value As Object, ByVal destType As Type) As Object
		'Return "(Collection)"
		If destType Is GetType(String) AndAlso TypeOf value Is Caption Then
			' Cast the value to an Caption type
			Dim emp As Caption = DirectCast(value, Caption)
			' Return the text for display.
			Return emp.Text
		End If
		Return MyBase.ConvertTo(context, culture, value, destType)
	End Function
End Class

' This is a special type converter which will be associated with the CaptionCollection class.
' It converts a CaptionCollection object to a string representation for use in a property grid.
Friend Class CaptionCollectionConverter
	Inherits ExpandableObjectConverter

	Public Overloads Overrides Function ConvertTo(ByVal context As ITypeDescriptorContext, ByVal culture As System.Globalization.CultureInfo, ByVal value As Object, ByVal destType As Type) As Object
		If destType Is GetType(String) AndAlso TypeOf value Is CaptionCollection Then
			' Return department and department role separated by comma.
			Return "(Collection)"
		End If
		Return MyBase.ConvertTo(context, culture, value, destType)
	End Function
End Class

Public Class CaptionCollectionPropertyDescriptor
	Inherits PropertyDescriptor
	Private collection As CaptionCollection = Nothing
	Private index As Integer = -1

	Public Sub New(ByVal coll As CaptionCollection, ByVal idx As Integer)
		MyBase.New("#" & idx.ToString(), Nothing)
		Me.collection = coll
		Me.index = idx
	End Sub

	Public Overloads Overrides ReadOnly Property Attributes() As AttributeCollection
		Get
			Return New AttributeCollection(Nothing)
		End Get
	End Property

	Public Overloads Overrides Function CanResetValue(ByVal component As Object) As Boolean
		Return True
	End Function

	Public Overloads Overrides ReadOnly Property ComponentType() As Type
		Get
			Return Me.collection.[GetType]()
		End Get
	End Property

	Public Overloads Overrides ReadOnly Property DisplayName() As String
		Get
			Return "Caption" + (index + 1).ToString()
		End Get
	End Property

	Public Overloads Overrides ReadOnly Property Description() As String
		Get
			Return "Caption" + (index + 1).ToString()
		End Get
	End Property

	Public Overloads Overrides Function GetValue(ByVal component As Object) As Object
		Return Me.collection(index)
	End Function

	Public Overloads Overrides ReadOnly Property IsReadOnly() As Boolean
		Get
			Return False
		End Get
	End Property

	Public Overloads Overrides ReadOnly Property Name() As String
		Get
			Return "#" & index.ToString()
		End Get
	End Property

	Public Overloads Overrides ReadOnly Property PropertyType() As Type
		Get
			Return Me.collection(index).[GetType]()
		End Get
	End Property

	Public Overloads Overrides Sub ResetValue(ByVal component As Object)
	End Sub

	Public Overloads Overrides Function ShouldSerializeValue(ByVal component As Object) As Boolean
		Return True
	End Function

	Public Overloads Overrides Sub SetValue(ByVal component As Object, ByVal value As Object)
		' this.collection[index] = value;
	End Sub
End Class

末级

推荐答案

我发现我的答案。我缺少的东西是这个属性的字幕属性：DesignerSerializationVisibility（DesignerSerializationVisibility.Content

I found my answer. The thing I was missing was this attribute in the Captions property: DesignerSerializationVisibility(DesignerSerializationVisibility.Content

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