Of 337 cities in China, 289 have been designated free of the virus. I believe that means no new cases within the past 14 days. There might be people still sick from the disease in hospital, as serious cases require up to 6 weeks of treatment. I'm not sure exactly. 48 cities still have had new cases in the past two weeks. I think Shanghai is up to 6 or 7 days without a new or suspected case. Hence the easing measures.
Officially Shanghai has had 394 cases, with 328 cured, 62 still under treatment and 4 deaths. That's of a population of approx 27M (including the near suburbs administered by Shanghai, which is a metropolitan area raised to the status of a province).