What does this mean?

[SPlatten]

This post is deleted!

[kkoehne]

Digging into qtdeclarative, it seems qmltyperegistrar only acknowledges .h , .hpp, .hxx, .hh file suffixes as header files, and warns otherwise:

            if (!include.endsWith(QLatin1String(".h"))
                    && !include.endsWith(QLatin1String(".hpp"))
                    && !include.endsWith(QLatin1String(".hxx"))
                    && !include.endsWith(QLatin1String(".hh"))
                    && !include.endsWith(u".py")
                    && include.contains(QLatin1Char('.'))) {
                fprintf(stderr,
                        "Class %s is declared in %s, which appears not to be a header.\n"
                        "The compilation of its registration to QML may fail.\n",
                        qPrintable(classDef.value(QLatin1String("qualifiedClassName"))
                                   .toString()),
                        qPrintable(include));
            }

[SPlatten]

@kkoehne , thank you.