Convert a SystemColors color to Color

[Ruffnekk]

I've been trying for hours to write a function that would return the real color (Color.Black for example) for SystemColors.WindowText and all of the other SystemColors and I finally (partially) succeeded. I just figured some of you might be looking for this as well and had a hard time (like me) finding a sample on the net.

'The function:
Public Function ToRealColor(ByVal systemColor As Color) As Color
  Dim iARGB As Integer = systemColor.ToArgb
  Dim realColor As Color = ColorTranslator.FromWin32(iARGB)
  Return realColor
End Function

'Calling the function and verify the result:
Dim RealColor As Color = ToRealColor(SystemColors.Windowtext)
MsgBox(RealColor.ToString)
'On my system it the msgbox shows "Color [Black]" as wished.

I could not find any other way to achieve this. So if there's something obvious I overlooked please let me know

Also, when the ARGB values of the provided color doesn't exactly match an ARGB value of a known Color structure, then the ToString method will return something like "Color [A=255, R=161, G=157, B=157]". I've tried fixing this with the GetNearestColor method of a Graphics object but without luck so far. Anyone?

Regards, Ruffnekk
---
Is it my imagination or do buffalo wings taste just like chicken?

 

[earthandfire]

Ruffnekk, I haven't as yet been able to solve the Color [A=255, R=161, G=157, B=157[/i] problem, however the following will enable you to get a complete list of all the "Window Element" colours:

Imports Microsoft.Win32
...
...
...
  Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

    Dim CurrentUser As RegistryKey = Registry.CurrentUser
    Dim ControlPanel As RegistryKey = CurrentUser.OpenSubKey("Control Panel")
    Dim Colors As RegistryKey = ControlPanel.OpenSubKey("Colors")
    TextBox1.Clear()
    Dim Names() As String = Colors.GetValueNames
    Dim rgbvals() As String
    Dim rgbval As Integer
    Dim col As String
    For a As Integer = 0 To Names.Length - 1
      rgbvals = Colors.GetValue(Names(a)).ToString.Split
      rgbval = RGB(CInt(rgbvals(0)), CInt(rgbvals(1)), CInt(rgbvals(2)))
      col = ColorTranslator.FromWin32(rgbval).ToString
      TextBox1.Text += Names(a) + " = " + _
                  Colors.GetValue(Names(a)).ToString + _
                        " [" + col + "]" + Environment.NewLine()
    Next
    Colors.Close()
    ControlPanel.Close()
    CurrentUser.Close()

  End Sub

The output form my machine is:

ActiveBorder = 212 208 200 [COLOR=[A=255, R=212, G=208, B=200]]
ActiveTitle = 10 36 106 [COLOR=[A=255, R=10, G=36, B=106]]
AppWorkSpace = 128 128 128 [COLOR=[Gray]]
Background = 58 110 165 [COLOR=[A=255, R=58, G=110, B=165]]
ButtonAlternateFace = 181 181 181 [COLOR=[A=255, R=181, G=181, B=181]]
ButtonDkShadow = 64 64 64 [COLOR=[A=255, R=64, G=64, B=64]]
ButtonFace = 212 208 200 [COLOR=[A=255, R=212, G=208, B=200]]
ButtonHilight = 255 255 255 [COLOR=[White]]
ButtonLight = 212 208 200 [COLOR=[A=255, R=212, G=208, B=200]]
ButtonShadow = 128 128 128 [COLOR=[Gray]]
ButtonText = 0 0 0 [COLOR=[Black]]
GradientActiveTitle = 166 202 240 [COLOR=[A=255, R=166, G=202, B=240]]
GradientInactiveTitle = 192 192 192 [COLOR=[Silver]]
GrayText = 128 128 128 [COLOR=[Gray]]
Hilight = 10 36 106 [COLOR=[A=255, R=10, G=36, B=106]]
HilightText = 255 255 255 [COLOR=[White]]
HotTrackingColor = 0 0 128 [COLOR=[Navy]]
InactiveBorder = 212 208 200 [COLOR=[A=255, R=212, G=208, B=200]]
InactiveTitle = 128 128 128 [COLOR=[Gray]]
InactiveTitleText = 212 208 200 [COLOR=[A=255, R=212, G=208, B=200]]
InfoText = 0 0 0 [COLOR=[Black]]
InfoWindow = 255 255 225 [COLOR=[A=255, R=255, G=255, B=225]]
Menu = 212 208 200 [COLOR=[A=255, R=212, G=208, B=200]]
MenuText = 0 0 0 [COLOR=[Black]]
Scrollbar = 212 208 200 [COLOR=[A=255, R=212, G=208, B=200]]
TitleText = 255 255 255 [COLOR=[White]]
Window = 255 255 255 [COLOR=[White]]
WindowFrame = 0 0 0 [COLOR=[Black]]
WindowText = 0 0 0 [COLOR=[Black]]
MenuHilight = 0 0 0 [COLOR=[Black]]
MenuBar = 212 208 200 [COLOR=[A=255, R=212, G=208, B=200]]

Hope this helps.

 

[earthandfire]

I think I have a solution. I wont have time to test it before the weekend, but here goes ...

Use Reflection
Iterate through the properties of System.Drawing.Color
You are only interested in the property if it is of type System.Drawing.Color
Use System.Drawing.ColorTranslator.ToWin32 against each colour to return an integer
Compare that integer with the result form my code above
**If it matches then you have got the colour's name (the property)


**If there is no exact match, then you can use an algorithm to determine proximity.
Either on the Delphi forum or the VB5/6 forum there is a post something like :

"How do I pick a suitable foreground colour for any given background colour?"

stromgm on the VB5/6 posted a pretty detailed colour related reply not that long ago - it may well be the post I'm referring to above.


Hope this helps - and I'll have a play this weekend unless you post the solution beforehand.

 

[Ruffnekk]

I'll have some play too 'cause it doing my head in right now *lol*. It's gone beyond the point of what I actually need, but it's some challenge.

Regards, Ruffnekk
---
Is it my imagination or do buffalo wings taste just like chicken?

 

[Ruffnekk]

Thanks for your input BTW, I can use that code

Regards, Ruffnekk
---
Is it my imagination or do buffalo wings taste just like chicken?

 

[earthandfire]

It's gone beyond the point of what I actually need, but it's some challenge

I know that feeling only too well!

 

[earthandfire]

One final thought and then its all yours until the weekend


The Registry only has the RGB values, but when converted the A value is built in (probably an arbitrary value). The Color properties that you will get via reflection will almost certainly contain a correct A value - so to ensure a like for like comparison, it would probably be a good idea to mask out the A value. As a guess this would involve ANDing the low 24 bits of the returned / derived integer.

Assuming ColorIntFromReg and ColorIntFromColor are the two variables then

ColorIntFromReg = ColorIntFromReg AND (2^24-1)
ColorIntFromColor = ColorIntFromColor AND (2^24-1)

If ColorIntFromReg = ColorIntFromColor etc etc.


Hope this helps.

 

[Ruffnekk]

Thanks again! I'll put it to use I think

Regards, Ruffnekk
---
Is it my imagination or do buffalo wings taste just like chicken?

 

[earthandfire]

Ruffnekk, I don't know how you got on with your testing, but I've had limited success. It seems that where no named colour is returned the colour doesn't have a defined name.

I've tried the following:

A couple of support functions:

  Private Function GetColorBreakdown(ByVal c As Color) As String

    Return c.R.ToString + " " + c.G.ToString + " " + c.B.ToString + " "

  End Function

  Private Function GetColorElementsValue(ByVal c As Color) As Integer

    Return c.R * 65536 + c.G * 256 + c.B

  End Function

A modified version of my original code:

  Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click

    Dim CurrentUser As RegistryKey = Registry.CurrentUser
    Dim ControlPanel As RegistryKey = CurrentUser.OpenSubKey("Control Panel")
    Dim Colors As RegistryKey = ControlPanel.OpenSubKey("Colors")
    Dim Names() As String = Colors.GetValueNames
    Dim rgbvals() As String
    Dim colint As Integer
    Dim kc As New KnownColor
    Dim ok As Boolean
    TextBox1.Clear()
    For a As Integer = 0 To Names.Length - 1
      rgbvals = Colors.GetValue(Names(a)).ToString.Split
      colint = Convert.ToInt32(rgbvals(0)) * 65536 + _
                      Convert.ToInt32(rgbvals(1)) * 256 + Convert.ToInt32(rgbvals(2))
      TextBox1.Text += Names(a) + " "
      ok = False
      For kc = 0 To KnownColor.YellowGreen
        If Not Color.FromKnownColor(kc).IsSystemColor Then
          If GetColorElementsValue(Color.FromKnownColor(kc)) = colint Then
            TextBox1.Text += Color.FromKnownColor(kc).Name + Environment.NewLine
              ok = True
              Exit For
            End If
          End If
      Next
      If Not ok Then
        TextBox1.Text += "[" + rgbvals(0) + " " + rgbvals(1) + " " + rgbvals(2) + "]" + Environment.NewLine
      End If
    Next
    Colors.Close()
    ControlPanel.Close()
    CurrentUser.Close()

  End Sub

A couple of other tests to enable me to paste data into Excel and do some further testing:

 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

    Dim CurrentUser As RegistryKey = Registry.CurrentUser
    Dim ControlPanel As RegistryKey = CurrentUser.OpenSubKey("Control Panel")
    Dim Colors As RegistryKey = ControlPanel.OpenSubKey("Colors")
    TextBox1.Clear()
    Dim Names() As String = Colors.GetValueNames
    Dim rgbvals() As String
    Dim rgbval As Integer
    Dim col As String
    For a As Integer = 0 To Names.Length - 1
      rgbvals = Colors.GetValue(Names(a)).ToString.Split
      rgbval = RGB(CInt(rgbvals(0)), CInt(rgbvals(1)), CInt(rgbvals(2)))
      col = ColorTranslator.FromWin32(rgbval).ToString
      TextBox1.Text += rgbvals(0) + " " + rgbvals(1) + " " + rgbvals(2) + " " + Names(a) + Environment.NewLine

      Dim xxx As String = System.Drawing.Color.FromArgb(rgbval).ToString
    Next
    Colors.Close()
    ControlPanel.Close()
    CurrentUser.Close()

  End Sub

  Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click

    Dim col As New KnownColor
    For col = 0 To KnownColor.YellowGreen
      If Color.FromKnownColor(col).IsSystemColor Then
        TextBox1.Text += GetColorBreakdown(Color.FromKnownColor(col)) + col.ToString + Environment.NewLine
      Else
        TextBox2.Text += GetColorBreakdown(Color.FromKnownColor(col)) + col.ToString + Environment.NewLine
      End If
    Next

  End Sub

Because I was experimenting the Excel cell references are not perhaps as logical as they may have been however:

The output from button1:
I1 to L31
The output from button5:
B30 to E170

Then in H1:
=I1*65536+J1*256+K1
(copied down)
And in A30:
=B30*65536+C30*256+D30
(copied down)
Then sort (using Data | Sort) on ColumnA

In G1:
Either: =VLOOKUP(H1,$A$30:$E$170,5,FALSE)
which returns the same info we had before
Or: =VLOOKUP(H1,$A$30:$E$170,5)
which return a colour for each UI element - picking the next lowest value form column A where there is no exact match.

Hope this helps.

 

[Ruffnekk]

I haven't gotten much further either. I was trying all weekend to write methods to always return a named color, which corresponds to the nearest match but it is getting too complicated. I'll post some code later when I get better results

Regards, Ruffnekk
---
Is it my imagination or do buffalo wings taste just like chicken?