title: Google map API Multiple marker click animation
body: <p>Google map has multiple marker clicks. Each marker has the corresponding info-window to display the content. How do I do that, when I click a marker to display info-window, turn off the last info-window?</p>
  
  <p>[Chinese — translate]
  google map API中，有多个marker点击每一个marker都有对应的info-window来展示内容，请问怎么实现点击一个marker展示info-window时把上一个info-window关掉？</p>