diff --git a/dist/web-greeter-bash b/dist/web-greeter-bash
index ab51e11..dcb7083 100644
--- a/dist/web-greeter-bash
+++ b/dist/web-greeter-bash
@@ -9,12 +9,13 @@ _web-greeter() {
 
 	case "${last}" in
 		--theme)
+			_filedir
 			options=$(ls -1d /usr/share/web-greeter/themes/*/ | cut -c 1- |
 				rev | cut -c 2- | rev | sort | sed 's/\/usr\/share\/web-greeter\/themes\///')
 			;;
 	esac
 
-	COMPREPLY=( $(compgen -W "${options}" -- "${cur}") )
+	COMPREPLY+=( $(compgen -W "${options}" -- "${cur}") )
 }
 
 complete -F _web-greeter web-greeter
diff --git a/dist/web-greeter-zsh b/dist/web-greeter-zsh
index 3de4b0b..e9d81d9 100644
--- a/dist/web-greeter-zsh
+++ b/dist/web-greeter-zsh
@@ -9,13 +9,19 @@ _webgreeter() {
         '--debug[Runs the greeter in debug mode]'
         '--normal[Runs in non-debug mode]'
         '--list[Lists available themes]'
-        "--theme[Sets the theme to use]:theme:(${themes})"
+        "--theme[Sets the theme to use]:theme:->themes"
         '--help[Show help]'
         '-h[Show help]'
         '--version[Print program version]'
         '-v[Print program version]'
     )
     _arguments $args[@] && ret=0
+    case "$state" in
+        themes)
+            _files
+            _values 'themes' "${(uonzf)${themes}}"
+            ;;
+    esac
     return ret
 }