固定间隔后获取纬度位置

对于速度测量应用程序，我需要在每四秒后获得经度和经度更新。 我在两次调用getLatitude和getLongitude函数之间使用了sleep函数。 但是在屏幕上打印显示值保持不变，即lon1和lon2，因为双精度数（十进制后的14位）具有完全相同的值，因此速度也显示为0。

如何在固定的时间间隔（此处为4秒）后获得纬度和经度？ 非常感谢提前。

locationManager = (LocationManager) getSystemService(LOCATION_SERVICE); locationListener = new LocationListener() { @Override public void onLocationChanged(Location location) { double r = 6371; double lat1 = location.getLatitude(); double lon1 = location.getLongitude(); // To get initial longitude SystemClock.sleep(4000); /////This seems ineffective. double lat2 = location.getLatitude(); double lon2 = location.getLongitude(); // and here double dlat = (lat2-lat1)*22/7/180; double dlon = (lon2-lon1)*22/7/180; textView.append("lon1:"+lon1+" lon2:"+lon2+" Kmph\n"); lat1 = lat1*22/7/180; lat2 = lat2*22/7/180; double h = ((1-Math.cos(dlat))/2) + Math.cos(lat1)*Math.cos(lat2)*(1-Math.cos(dlon))/2; double d = 2**Math.asin(Math.sqrt(h)); double sp = d/3; textView.append(" "+ sp + " Kmph\n"); } @Override public void onStatusChanged(String s, int i, Bundle bundle) { } @Override public void onProviderEnabled(String s) { } @Override public void onProviderDisabled(String s) { Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS); startActivity(intent); } }; if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M){ if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) { requestPermissions(new String[]{ Manifest.permission.ACCESS_FINE_LOCATION,Manifest.permission.ACCESS_COARSE_LOCATION, Manifest.permission.INTERNET },10); return; } }else { configureButton(); } } @Override public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) { switch (requestCode) { case 10: if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) configureButton(); return; } } private void configureButton() { button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { locationManager.requestLocationUpdates("gps", 4000, 0, locationListener); } }); } } 

Answer 1

嘿，我不确定，但你看起来像这样希望这会对你有所帮助。

  float oldlat, oldlng; float currentLat, currentLng; // Use this in location changed currentLat = (float) location.getLatitude(); currentLng = (float) location.getLongitude(); final Handler handler = new Handler(); handler.postDelayed(new Runnable() { @Override public void run() { oldlat = (float) location.getLatitude(); oldlng = (float) location.getLongitude(); } }, 4000);