[RESOLVED] SetParent vs. ExtFloodFill

[Fedhax]

Here's the current arrangement of my form: I have a form (Form1) with a frame (Fra1) on it. I'm using SetParent to insert a second form (Form2) into the frame.

Form1 > Fra1 >Form2

Now, I call TransparentBlt to transfer an image onto Form2. When I want to use ExtFloodFill to fill in a region of that picture, the function executes, returns TRUE, and I call Form2.Refresh, but no colors are updated on the screen. However, if I start Form2 by itself and try the TransparentBlt > ExtFloodFill > Form2.Refresh, everything works as expected.

Would there be a reason the setting the parent of the form is affecting the way it is colored/APIs affect it? If so, what are some possible solutions to this issue?

From Form2:

Private Sub Form_Load()
    
    Dim hBitmap         As Long
    Dim hdc             As Long
    Dim hFraDc          As Long
    
    ' Preparing the image
    hdc = CreateCompatibleDC(GetDC(0))
    
    hBitmap = LoadImage(App.hInstance, App.Path & "\Images\test01.bmp", IMAGE_BITMAP, 300, 200, LR_LOADFROMFILE)
    SelectObject hdc, hBitmap
    TransparentBlt Me.hdc, 10, 30, 300, 200, hdc, 0, 0, 300, 200, vbWhite
    
    Me.Refresh
    DeleteObject hBitmap
    
    mBrush = CreateSolidBrush(crNewColor)
    SelectObject Me.hdc, mBrush
    Me.ScaleMode = vbPixels
    
    ' Showing in Frame, Don't need Me.Show
    'Me.Show
 
End Sub
 
Private Sub Form_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
    'Floodfill...
    ExtFloodFill Me.hdc, X, Y, GetPixel(Me.hdc, X, Y), FLOODFILLSURFACE
    Me.Refresh
End Sub
 
Private Sub Form_Unload(Cancel As Integer)
    DeleteObject mBrush
End Sub