gio:settings-schema-source-list-schemas (source recursive)

source -- a g:settings-schema-source instance
recursive -- a boolean whether the lookup should be recursive
non-relocatable -- a list of strings for the non-relocatble schemas
relocatable -- a list of strings for the relocatable schemas

Lists the schemas in a given source. If recursive is true then include parent sources. If false then only include the schemas from one source, that is one directory. You probably want true.

Non-relocatable schemas are those for which you can call the g:settings-new function. Relocatable schemas are those for which you must use the g:settings-new-with-path function.

Do not call this function from normal programs. This is designed for use by database editors, commandline tools, and so on.