[2008] Type Converter Question

[tim8w]

I have written a Type Converter for a TrackBar. I was wondering if there is any way to get the value being changed in the Dropdown so I can update the PropertyGrid item value dynamically instead of just at the end?

Here is the Type Converter code:

Imports System.Windows.Forms.Design

Public Class Slider
Private editorService As IWindowsFormsEditorService

Private m_Value As Integer

Public Property Value() As Integer
Get
Return m_Value
End Get
Set(ByVal value As Integer)
m_Value = value
End Set
End Property

Public Sub New()
' This call is required by the Windows Form Designer.
InitializeComponent()

' Add any initialization after the InitializeComponent() call.
tbSlider.LargeChange = 25
tbSlider.SmallChange = 10
tbSlider.TickFrequency = 15
tbSlider.Maximum = 255
tbSlider.Minimum = 0
tbSlider.Size = Me.Size

Me.editorService = editorService

End Sub

Public Sub New(ByVal MyValue As Integer, ByVal MyLargeChange As Integer, ByVal MySmallChange As Integer, ByVal MyTickFrequency As Integer, ByVal MyMinimum As Integer, ByVal MyMaximum As Integer, ByVal editorService As IWindowsFormsEditorService)
' This call is required by the Windows Form Designer.
InitializeComponent()

' Add any initialization after the InitializeComponent() call.
tbSlider.LargeChange = MyLargeChange
tbSlider.SmallChange = MySmallChange
tbSlider.TickFrequency = MyTickFrequency
tbSlider.Maximum = MyMaximum
tbSlider.Minimum = MyMinimum
tbSlider.Value = MyValue

Me.editorService = editorService

End Sub

Private Sub tbSlider_ValueChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles tbSlider.ValueChanged

m_Value = CInt(tbSlider.Value)
End Sub
End Class

Here is the Property Code:


<System.ComponentModel.Category("Appearance"), _
System.ComponentModel.DefaultValue("200"), _
System.ComponentModel.Editor(GetType(OpacitySliderEditor), GetType(System.Drawing.Design.UITypeEditor)), _
System.ComponentModel.Description("Value that represents a change in the Opacity or transparency of the control.")> _
Public Property Opacity() As Integer
Get
Return m_Opacity
End Get
Set(ByVal value As Integer)
m_Opacity = value
SetBkImage()
Me.Invalidate()
End Set
End Property

[dglienna]

I don't know if you can get the dropdown to change positions according to the slider. Might be easier to use a textbox or label control, though.

Isn't there a .value of something for the slider properties?

[tim8w]

I don't want the DropDown to change, just to be able to update the associated PropertyGrid value as the TrackBar moves...

[dglienna]

Use the CLICK event of the slider (as previously mentioned).

You can create an event that fires automatically

[tim8w]

There is no Click event, but I am trapping the ValueChanged() event and setting the Value. The problem is that this Value isn't passed back to the PropertyGrid until the slider has closed...


Private Sub tbSlider_ValueChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles tbSlider.ValueChanged

m_Value = CInt(tbSlider.Value)
End Sub

[dglienna]

No MouseDown, or MouseUp? I thought that was a way to trap movement (don't have vs here)

[tim8w]

The problem has to be in the TypeEditor code. Right now once the DropDown in the TypeEditor has control, the PropertyGrid value doesn't get updated until the DropDown completes...

Here's the TypeEditor Code:


Imports System.ComponentModel
Imports System.Drawing.Design
Imports System.Windows.Forms.Design

Public Class cOpacitySlider
Friend Class OpacitySliderEditor
Inherits UITypeEditor
Private editorService As IWindowsFormsEditorService

Public Overrides Function GetEditStyle(ByVal context As System.ComponentModel.ITypeDescriptorContext) As System.Drawing.Design.UITypeEditorEditStyle
Return UITypeEditorEditStyle.DropDown
End Function

Public Overrides Function EditValue(ByVal context As System.ComponentModel.ITypeDescriptorContext, ByVal provider As System.IServiceProvider, ByVal value As Object) As Object
If Not (provider Is Nothing) Then
editorService = _
CType(provider.GetService(GetType(IWindowsFormsEditorService)), _
IWindowsFormsEditorService)
End If

If Not (editorService Is Nothing) Then
Dim selectionControl As New Slider(CType(value, Integer), 25, 10, 15, 0, 255, editorService)

editorService.DropDownControl(selectionControl)

value = selectionControl.Value
End If

Return value

End Function
End Class
End Class

[dglienna]

See if you can use Invalidate. Maybe the slider? If nothing else, then the form itself?