Question

Using the following code to write a string to the DesktopWindow’s device context works, but the background color and text color remain the same (white on blue):

Private Sub writeToScreen(txt As String)
Declare Function GetDesktopWindow Lib "user32" () As Integer
Declare Function DrawTextW Lib "user32" (hdc As Integer, lpStr As WString, nCount As Integer, _
     ByRef lpRect As RECT, wFormat As Integer) As Integer
Declare Function CreateDCA Lib "gdi32" (lpDriverName As CString, lpDeviceName As Integer, _
     lpOutput As Integer, lpInitData As Integer) As Integer
Declare Function DeleteDC Lib "gdi32" (hdc As Integer) As Integer
Declare Function GetTextColor Lib "gdi32" (hdc As Integer) As Color
Declare Function SetTextColor Lib "gdi32" (hdc As Integer,  crColor As Color) As Color
Declare Function GetBkColor Lib "gdi32" (hdc As Integer) As Color
Declare Function SetBkColor  Lib "gdi32" (hdc As Integer,  crColor As Color) As Color

Const DT_MULTILINE = &H00000001
Const DT_NOCLIP = &H100
Const INVALID_COLOR = &hFFFFFFFF

Dim tFormat As Integer = DT_MULTILINE Or DT_NOCLIP
Dim hdc As Integer = CreateDCA("DISPLAY", 0, 0, 0)
Dim tRect As RECT   //The RECT structure is defined elsewhere
Dim textCol, backColor As Color

tR.Left = 200
tR.Top = 250
tR.Right = 600
tR.Bottom = 350
textCol = SetTextColor(hdc, &cFF8040)
backColor = SetBkColor(hdc, &c000000)

If DrawTextW(hdc, txt, Len(txt), tR, tFormat) = 0 Then
  System.DebugLog("Text Draw Error")
End If

Call SetTextColor(hdc, textCol)
Call SetBkColor(hdc, backColor)
Call DeleteDC(hdc)  
End Sub

What am I doing wrong? The text gets written just fine, but the colors are ugly.

Answer 1

Use SetBkMode() (http://msdn.microsoft.com/en-us/library/dd162965%28v=vs.85%29.aspx) first to set the DC to not draw a background.

SetTextColor() is only used for TextOut(), not DrawText(), IIRC – MSDN is ambiguous on it. Try seleting a different HBRUSH into the DC, that may do what you want.