#1525 [Patch] Add SCI_CALLTIPSETFOREBORDER

[Martijn Laan]

Here's a patch which adds a SCI_CALLTIPSETFOREBORDER message to set the two colours used for the border of call tips.

Without this message call tips aren't really usable in a dark mode container because the bottom and right border colours are hardcoded to be black, making the border invisible or barely visible.

Additionally containers on Windows which use SC_AUTOCOMPLETE_FIXED_SIZE can use this message to give call tips a border which is consistent with the autocomplete border by setting both colors to Windows color COLOR_WINDOWFRAME.

The patch includes updates of Scintilla.iface and ScintillaDoc.html.

https://patch-diff.githubusercontent.com/raw/jrsoftware/scintilla/pull/9.diff
https://patch-diff.githubusercontent.com/raw/jrsoftware/scintilla/pull/9.patch
https://github.com/jrsoftware/scintilla/pull/9/files

[Neil Hodgson]

These could be implemented as element colours.

[Martijn Laan]

Ok, thanks. I guess that means the updated patch should add element colours for the other calltip colors as well?

[Neil Hodgson]

Just concentrate on the border for now. Scope creep is the major cause of enhancement failure.

[Neil Hodgson]

Its likely worth checking the current Windows UI guidelines (unsure where they are now) to see what is recommended for tips. I expect conformance to the Windows-11 look would de-emphasize the border and use a 3D shadow.

[Martijn Laan]

I've looked at implementing it as an element colour but am unsure how to do this properly.

[Neil Hodgson]

It would be best to study one of the autocompletion elements as an exemplar such as Element::ListBack. This is an opaque colour like the calltip borders and picks up system setting colours.

However, the 3D border appearance used for calltips currently may appear old-fashioned. The nearest design I could find in the current UI guidelines is for tooltips which are mostly indicated by a shadow and have a soft border.
https://learn.microsoft.com/en-us/windows/apps/design/controls/tooltips
Maybe the appearance used by Visual Studio would match user expectations closer.