Question

我正在尝试从提供分页响应的REST端点获取数据。在按钮上单击flutter，我想获得响应中的下一个项目。我想想我想使用一个Stream来抽象出请求的分页性质，并自动轮询下一个结果。

像这样的dartish伪代码：

我觉得可能Stream<String> nextUrl(int lastPage=0) { // Get paginated response batch = server.getResponse(lastPage) for (item in batch) { yield item; } // Recurse automatically // Not a problem if the stream is suspended // after every item request. A big problem // if the stream never pauses. await for (String item in nextUrl(lastPage++) { yield item; } } // In flutter class WidgetState extends state<MyPage> { Stream<String> urlStream = new nextUrl(0); String currentItem; ... @override Widget build(BuildContext context) { return new InkWell( onTap: () { (() async { // This is the call I haven't figured out. await item = urlStream().getNext(); setState(() { currentItem = item; }); })(); } ); } }之类的东西不存在？我应该暂停/取消暂停此流？但是我不确定那样一次只返回一个项目。

Answer 1

async包提供允许执行此操作的StreamQueue

var events = new StreamQueue<String>(yourStream);
var first = await events.next;
while (...) {
  ...
  first = await events.next;
}

一次从一个项目请求数据？

1 个答案: