JScript-based (https://en.wikipedia.org/wiki/JScript) javascript scripting of ActiveX controls seem to be partly broken in Qt. VBScript-based scripting, however, seem to work fine based on the "testcon" sample scripts.

STEPS TO REPRODUCE:

• Build the src\activeqt\container, examples\activeqt\multiple & tools\testcon projects in the QtActiveQt repo.
• Start "testcon", then insert the QAxWidget2 control (part of the "multiple" project).
• Load "tools\testcon\scripts\vbscript.vbs", select run macro and verify that both the "fatLines()" and "setLineWidth(QVariant)" functions modify line width in QAxWidget2 when called.
• Restart "testcon", then insert the QAxWidget2 control again.
• Load "scripts\vbscript.js", select run macro and verify that "setLineWidth(QVariant)" does work, whereas "fatLines()" fails silently.

Both the JScript and VBscript scripting engines report to support introspection by QAxScriptEngine::hasIntrospection, so lack of introspection support is not the direct reason.

Qt 4: JavaScript causes an assert crash.