VB6 app icon in Windows 7 taskbar is blurred

1
votes

I have a VB6 application and one of the Form icon is set as application icon. The problem is that in Windows 7 the icon looks blurred even though the icon contains 16x16, 32x32 and 48x48 sizes.

Is there a way around this problem? It tried the SendMessage(... SETICON... ICON_BIG) but it does not seems to work.

2
vb6windows-7-x64taskbar
Which hWnd did you try to SendMessage to? Try to send it to GetParent(Form1.hWnd) which is the hidden single owner of every VB6 "ownerless" form that holds the icon in Applications tab in Task Manager. – wqw
Where does the icon appear blurred? On the Form or when looking at the exe in Windows Explorer? – Matt Wilko
@Matt The title says it's in the Windows 7 taskbar. – Martin

2 Answers

2
votes

What colour depth are the icons in your ico file?

VB6 (I believe) supports a maximum 8 bit colour depth (256 colours) for icons:-

So if there is no size 48 x 48 icon in 8 bit colour depth it could be using the nearest match and scaling it to 48 x 48

EDIT:

I just tried this using an icon that did not have a 48 x 48 icon at 8 bit depth (but did have 48 x 48 at higher depths) and the icon used in the taskbar was the 32bit icon at 8 bit colour depth.

0
votes

I don't claim to understand the full heuristics used to choose the icon image to display in various places, but I think what is happening here is that your 48x48 image is being taken and scaled down.

I suspect what happens with a VB6 program on many versions of Windows is that if there is no 16-color 16x16 image then a larger size gets taken and scaled. The reason may simply be due to the order of the images in the ICO resource/file.

If you edit your ICO and add a 16-color version of your 16x16 image your "problem" may disappear.