On Wed Apr 22 11:11:54 2026 +0000, Zhiyi Zhang wrote:
[treeview_force_ansi.txt](/uploads/e0d52b926ceacd430828862a377ccafd/treeview_force_ansi.txt) I tried handling WM_NOTIFYFORMAT with NF_QUERY and returning NFR_ANSI. I also tried sending to the child a WM_NOTIFYFORMAT with NF_REQUERY, TVM_SETUNICODEFORMAT with ANSI specified, CCM_SETUNICODEFORMAT with ANSI specified. None of them changes the result. The parent class is registered with RegisterClassA(). DefWindowProcA() is called. The parent and child are created with CreateWindowExA(). I tried Win7/10 with 32-bit and 64-bit version of the test program. Maybe it's indeed a bug on the native. The NMTVITEMCHANGE struct doesn't have a text field. Ok, I see this is mentioned online too, when people were confused why they are getting W change notifications for those two cases, but A for everything else. So this must be just the way it works.
-- https://gitlab.winehq.org/wine/wine/-/merge_requests/10451#note_137333