Since qpdfview is part of Arch's official repos it will be included in a future releases unless it is plagued with freedom issues which necessitate its removal. In the meantime you can install it via Arch's PKGBUILD which can be found in the "source files" section of the package's page by using the "makepkg -s" command (you might need to add missing GPG keys to your keyring using "gpg--recv-keys"  if the makepkg command complains about missing keys).