問題描述
我正在通過 LocationManager.requestLocationUpdates() 使用 LocationManager.GPS_PROVIDER 跟蹤 GPS 位置并注冊 LocationListener.
I'm tracking GPS locations with LocationManager.requestLocationUpdates() using LocationManager.GPS_PROVIDER and registering a LocationListener.
我的問題:
所有經過測試的設備(Sony neo、Sony active、Moto G)都會生成 Location 對象，這些對象在其 getTime() 中沒有幾分之一秒:
All tested devices (Sony neo, Sony active, Moto G) produce Location objects which do not have fractions of a second in their getTime():
<trkpt ...><time>2014-05-24T10:24:59.000Z</time></trkpt>
<trkpt ...><time>2014-05-24T10:25:00.000Z</time></trkpt>
<trkpt ...><time>2014-05-24T10:25:01.000Z</time></trkpt>
<trkpt ...><time>2014-05-24T10:25:02.000Z</time></trkpt>
<trkpt ...><time>2014-05-24T10:25:03.000Z</time></trkpt>
當我計算速度、傾斜和與氣壓高度合并時，1 秒(1000 毫秒)的分辨率太不精確了.而且我不相信所有的修復都是完全在.000.
As I'm calculating speed, incline and merge with barometic altitude, 1s (1000ms) resolution is way too imprecise. And I do not believe, that the fixes are all exactly at .000.
我的問題:
最好將 System.currentTimeMillis() 作為我的跟蹤點的時間戳，或者 GPS 定位通常遠??遠落后于實時"，并且計算出的位置實際上是來自過去(落后幾秒)?
Is is better to take System.currentTimeMillis() as the timestamp for my track-points, or is the GPS fix generally far behind "real time" and the calculated positions are actually those from the past (several seconds behind)?
備注:
- 我知道在使用 GPS 數據時速度計算并不精確且相當復雜
- 這不是 Matching Location.getTime() 毫秒到 NMEA 語句 的副本
推薦答案
根據我的經驗，System.currentTimeMillis() 是一種更好的獲取時間戳的方法，這就是我正在做的事情我的應用程序.但是，請注意，如 android 開發者網站所述，System.currentTimeMillis() 返回自 1970 年 1 月 1 日 00:00:00.0 UTC 以來的當前時間(以毫秒為單位) 所以它真的取決于什么你想用它.正如我所提到的，我發現它比其他形式的時間戳更可靠，它可能最適合您的情況.
In my experience, System.currentTimeMillis() is a much better way to take timestamps, and it is what I am doing in my app. However, please be advised that, as stated on the android developer site, System.currentTimeMillis() Returns the current time in milliseconds since January 1, 1970 00:00:00.0 UTC so it really depends on what you want to use it for. As I mentioned though, I found it to be more reliable than other forms of timestamps and it is probably best suited for your case.
這篇關于Location.getTime() 總是返回沒有毫秒的時間戳的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！