PostRatings and Rich Snippets – how to do ?

It will work out of the box. You can test it using https://www.google.com/webmasters/tools/richsnippets

I already tried to check with Rich Snippets Google tool and they are not visible. It likes Google does not see them.

I should see something like :

Item 1
type: https://schema.org/aggregaterating
property:
ratingvalue: 3.5
reviewcount: 7

Item 12
type: https://schema.org/rating
property:
ratingvalue: 4.0

I can’t reproduce the problem on the default theme, https://www.google.com/webmasters/tools/richsnippets?q=http%3A%2F%2Flesterchan.net%2Fwordpress_dev%2F2014%2F03%2F11%2Ftest-showhide%2F (at the bottom)

Check your Ratings -> Options and ensure that “Enable Google Rich Snippets?” is Yes

ok fixed.

Big thanks ! Great support !