ICONWRKS under VB4
Posted on 1997-04-29
(also posted to comp.lang.basic.visual.misc)
I'm having trouble getting ICONWRKS to work properly under VB4.0 (16-bit) either with Win3.1 or Win95. I know that VB 4.0 has some advanced graphics capabilities over VB 3.0 (which is where ICONWRKS came from) but I'm using ICONWRKS to understand API programming as described in Appleman's "Visual Basic Programmer's Guide to the Windows 3.1 API.
A friend of mine still has VB3.0 and ICONWRKS works fine both under Win3.1 and Win95.
I've noticed that after fixing a few initial VB3.0 -to- VB4.0 style bugs
that the programs runs enough to allow me to edit in the pic_edit
picture box (that's the one the user sees) but when the pic_edit_mouse_up event occurs, the copy of the current icon over in the status area doesn't update. This copy of the icon is what gets saved to a file using the SavePicture statement. My problem is that none of my edits make it to the file (whatever.ICO)
I've traced through the program after pic_edit_mouse_up and have come to a critical point with the update_icon subroutine. First I noticed that the source code used integers for the GetBitmapBits
function return when the (Win 3.1) API calls for long. Also they pass numeric constants without enforcing integer vs. long but I guess VB takes care of that.
They copy bits from the pic_image and pic_mask to pic_icons(currentIcon) by BitBlt-ing the monochrome mask bits through a compatible memory device context (monohdc) and GetBitmapBits & GlobalLock to copy them to pic_icon(currentIcon).picture_base_address+12. The image bits are copied by GetBitmapBits from pic_image.image to
pic_icons(currentIcon).picture + 12 + 128. Then they force a paint event on pic_icons(currentIcon). This all works under 3.0 (even with improper API function return types) but not for my case.
Since the problem moves with VB version and is independent of Win3.1 vs. Win95 could there have been a change in internal graphics controls' memory layout from 3.0 to 4.0? Is the internal structure of .picture and .image detailed anywhere?
Did I miss a release notes file? Should I be taking a different diagnosis track?
I have pro edition. I have not looked into the CDK.
Thanks for any and all help,
Digital Equipment Corp