我猜您将需要一个如下所示的eventListener：

document.addEventListener("visibilitychange", (event) => {
  if (document.visibilityState == "visible") {
    console.log("tab is active")
  } else {
    console.log("tab is inactive")
  }
});

在你的 dart 代码里你必须倾听变化
Flutter (Web) how to listen to javascript event or pass javascript data to flutter?