Android模拟GPS数据生成kml和nmea文件
在Android平台上开发可能没有真机的时候，我们通过DDMS中载入KML或NMEA文件来模拟生产数据，使用方法参考 新版ADT插件让Android开发更人性化 一文，最终这两个文件加载到/data/misc/location/gps/nmea或/data/misc/location/gps/kml/
一、KML文件其实是一个XML文件，我们看下KML文件结构
<?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://earth.google.com/kml/2.2">
<Document>
<name>1065 Brea Mall, Brea, CA 92821.kml</name>
<StyleMap id="default_copy0+nicon=http://android.tgbus.com/UploadFiles_4504/200812/20081211111051749.png">
<Pair>
<key>normal</key>
<styleUrl>#default_copy0+icon=http://android.tgbus.com/UploadFiles_4504/200812/20081211111052637.png</styleUrl>
</Pair>
<Pair>
<key>highlight</key>
<styleUrl>#default_copy0+icon=http://android.tgbus.com/UploadFiles_4504/200812/20081211111052944.png</styleUrl>
</Pair>
</StyleMap>
<Style id="default_copy0+icon=http://android.tgbus.com/UploadFiles_4504/200812/20081211111052944.png">
<IconStyle>
<scale>1.1</scale>
<Icon>
<href>http://android.tgbus.com/UploadFiles_4504/200812/20081211111052944.png</href>
</Icon>
</IconStyle>
<LabelStyle>
<scale>1.1</scale>
</LabelStyle>
</Style>
<Style id="default_copy0+icon=http://android.tgbus.com/UploadFiles_4504/200812/20081211111052637.png">
<IconStyle>
<Icon>
<href>http://android.tgbus.com/UploadFiles_4504/200812/20081211111052637.png</href>
</Icon>
</IconStyle>
</Style>
<Placemark>
<name>1065 Brea Mall, Brea, CA 92821</name>
<address>1065 Brea Mall, Brea, CA 92821</address>
<LookAt>
<longitude>-117.883593</longitude>
<latitude>33.916991</latitude>
<altitude>0</altitude>
<range>1000</range>
<tilt>0</tilt>
<heading>0</heading>
</LookAt>
<styleUrl>#default_copy0+nicon=http://android.tgbus.com/UploadFiles_4504/200812/20081211111051749.png</styleUrl>
<Point>
<coordinates>-117.883593,33.916991,0</coordinates>
</Point>
</Placemark>
</Document>
</kml>
二、NMEA协议就是常规的GPS数据，通过串口直接获取到的，如下
$GPRMC,003347.000,A,3725.3433,N,12205.7920,W,0.08,149.46,061007,,,D*70
$GPRMC,003348.000,A,3725.3433,N,12205.7921,W,0.05,142.51,061007,,,D*7E
$GPRMC,003349.000,A,3725.3432,N,12205.7921,W,0.08,159.56,061007,,,D*7E
$GPRMC,003350.000,A,3725.3432,N,12205.7921,W,0.06,151.59,061007,,,D*7F
$GPRMC,003351.000,A,3725.3432,N,12205.7921,W,0.20,120.57,061007,,,D*72
实例:
解析方法:
RMC = Recommended Minimum Specific GPS/TRANSIT Data
$GPRMC,hhmmss.ss,A,llll.ll,a,yyyyy.yy,a,x.x,x.x,ddmmyy,x.x,a*hh
1 = UTC(universal time, coordinated) of position fix
2 = Data status (A=good, V=navigation receiver warning)
3 = Current Latitude
4 = North/South in Latitude Hemisphere
5 = Current Longitude
6 = East/West in Longitude Hemisphere
7 = Speed over ground in knots
8 = (Direction of travel N:0°, E:90°, S:180°, W:270°)
9 = UT DateStamp
10 = Magnetic variation degrees (Easterly var. subtracts from true course)
11 = East/West
12 = Checksum
$GPRMC,003347.000,A,3725.3433,N,12205.7920,W,0.08,149.46,061007,,,D*70
Parts:
1: 003347.000 --> 0:33 am 47 seconds 0 milliseconds (UTC(universal time, coordinated) of position fix)
2: A --> Status is ok (Data status (A=good, V=navigation receiver warning))
3: 3725.3433 (North/South in Latitude Hemisphere)
4: N --> North (North/South)
5: 12205.7920 (Current Longitude)
6: W --> West (East/West in Longitude Hemisphere)
7: 0.08 --> 0.08 knots/second (Direction: North/West) (Speed over ground in knots)
8: 149.46 --> sth. like SouthEast (Direction of travel N:0°, E:90°, S:180°, W:270°)
9: 061007 --> 6th October, 2007 (UT(universal time) DateStamp)
10: <empty> (Magnetic variation degrees (Easterly var. subtracts from true course))
Android GPS使用部分代码：
public class h extends Activity
{
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
LocationManager m_lm ;
GPS gps = new GPS();
m_lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
m_lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000L, 500.0f, gps);
}
}
public class GPS implements LocationListener
{
public void onLocationChanged(Location lc)
{
if (lc != null)
{
long latitude = lc.getLatitude();
long longitude =lc.getLongitude();
}
}
public void onStatusChanged(java.lang.String arg0, int arg1, Bundle extras)
{
// ignore
}
public void onProviderEnabled(java.lang.String arg0)
{
// ignore
}
public void onProviderDisabled(java.lang.String arg0)
{
// ignore
}
}