I found a huge design flaw with ListView_GetGroupMetrics (aka LVM_GETGROUPMETRICS) and I think this flaw is the reason the newsgroups do not mention this macro.

Basically this macro is supposed to return the metrics of a group in a listview, but none of the parameters in the data structure specify which group you want the info on!  I'm trying to find the size of a group header and the rectangle that group's items are sitting in and due to this I can't!  This is a really big mistake and I hope it gets fixed soon, the functionality is absolutely useless without this information!

While I'm at it, does the API provide any other way to get at this information?  Didn't think so :(

Another problem with using this macro (or its corresponding message) is that the flags are not defined.  The help says you can use LVGMF_BORDERCOLOR,
LVGMF_BORDERSIZE, LVGMF_NONE, and LVGMF_TEXTCOLOR.  If you use them, and even if you've included the required header Commctrl.h, you'll discover the compiler has no clue what you're talking about.

Any chance this was a feature that was never intended for public use and that's why it doesn't work or even have the necessary flags available?  I'm curious because I might force 0xffffffff into the flag field and see if it can somehow generate useful information anyway.