为什么 locationmanager 使用新的 gettime-timestamp 返回旧的位置修复？
我们有一个应用程序，根据用户操作尝试获取位置修复。它在 GPS 和网络上监听，并具有基于时间/准确性的决策矩阵，以确定何时停止监听以及返回哪些修复。
有时，我们注意到一种非常奇怪的行为。我们使用经典的方法来查看修复的时间有多长，如下所示：
long age = now - newLocation.getTime();
if(age >= prefs.getLocationMaxAge()){
Log.d(TAG, "location too old.");
return;
}
但有时，根据返回的时间戳，从操作系统返回的 location.getTime 的年龄可能为 15-20 秒，尽管我们可以确定它很旧了。例如，如果经度/纬度定位来自手机 30 分钟前所在的位置！
似乎 Wi-Fi 和网络都会发生这种情况，但 GPS 不会发生这种情况。对我来说，这完全是疯狂的。有其他人看到过这个吗？有什么办法可以解决吗？
我们已经在几款不同的手机上安装了该功能，最近的一款是 三星 Galaxy S II。
非常欢迎提供帮助。
编辑：要真正清楚的是，问题是操作系统调用“onlocationchanged”回调，其时间戳年龄可能为几秒，当我确定经度时“新”修复中的 /latitude 是手机至少 30 分钟没有出现过的地方。
这使得很难准确地确定手机的位置......
We have an app that upon user action tries to get a location fix. It listens both on GPS and network and has a time/accuracy based decision matrix to determine when to stop listening and what fix to return.
We have noticed, on occasion, a very strange behaviour. We use the classic way to see how old the fix is, like so:
long age = now - newLocation.getTime();
if(age >= prefs.getLocationMaxAge()){
Log.d(TAG, "location too old.");
return;
}
But sometimes, the location.getTime returned from the OS has an age of perhaps 15-20 seconds, according to the returned timestamp, although we can tell for certain that it's very old. For example, if the longitude/latitude fix is from a position that the handset was on 30 minutes ago!
It seems to happen both from Wi-Fi and network, but not GPS. To me, this is totally crazy. Has anyone else seen this and is there any way around it?
We have gotten it on a couple of different phones, most recent one is Samsung Galaxy S II.
Help would be extremely welcome.
EDIT: To be really clear, the problem is that the "onlocationchanged" callback gets called by the OS with a location with a timestamp age of perhaps a couple of seconds, when I know for certain that the longitude/latitude in the "new" fix is a place where the phone hasn't been at for at least 30 minutes.
This makes it kind of hard to accurately determine where the handset it...
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这似乎很公平，因为在基于 Wi-Fi 和网络蜂窝基站的三角测量中，精度非常差。他们可能正在使用可追溯到 30 分钟前的缓存位置。除非您没有更改您的蜂窝基站或移动到另一栋建筑物，以便可以发现新的AP ，恐怕您只会获得缓存的位置。如果您想要新的位置，请使用 GPS 提供商。
This seems fair, because in the Wi-Fi and network cell-site based triangulation, the accuracy is very bad. They are probably using cached locations which date back to 30 minutes ago. Unless you have not changed your cell-site or moved to another building so that new APs can be discovered, I'm afraid you will get only cached locations. If you want fresh locations use the GPS provider.