package - Linux Packaging - Program icon not appearing in GNOME 3 -

i'm new linux, made first linux application. created .deb .rpm , .pkg.tar.xz packages , have been testing them on various distributions , desktop environments.

i've tested cinnamon, xfce, kde , unity , packages work correctly, in gnome 3 i'm having problem application icon doesn't appear. case on both fedora gnome 3 , opensuse gnome 3, , other distribution running gnome 3.

i've found forcing icon cache update below command cause application icon start appearing in gnome 3.

gtk-update-icon-cache /usr/share/icons/hicolor 

installing application after installing package fixes application icon. therefore seems other packages somehow forcing icon cache update, i'm not sure how.

how package application forces icon cache update , works correctly gnome 3?

also, i've tested gnome 3 rpm based distributions. issue unique .rpm or have modify .deb , .pkg.tar.xz well?

thanks in advance.

see:

https://fedoraproject.org/wiki/packaging:guidelines#icon_tag_in_desktop_files

and snippet:

https://fedoraproject.org/wiki/packaging:scriptlets#icon_cache