Fix file dialog type, which sometimes breaks build [#152]

[jjdredd]

Checklist

• [x] Closing issues: #152
• [ x] Mark this if you consider it ready to merge (if it isn't can't I just make a draft pr instead of having this checkbox here?)
• [ ] I've added tests (optional)
• [ ] I wrote some documentation On some configurations, the compiler wants a type cast because it can't automatically cast 0 to one of the enum members