Android GPS Programming

1. enable the system GPS Service

Locationmanager = (locationmanager) This. getsystemservice (context. location_service );
If (locationmanager. isproviderenabled (Android. Location. locationmanager. gps_provider ))
{
Toast. maketext (this, "GPS module normal", Toast. length_short). Show ();
Return;
}

2. Set service information to be queried (fill location data class criteria)

// Query accuracy: high
Criteria. setaccuracy (criteria. accuracy_fine );
// Whether to query the altitude: Yes
Criteria. setaltituderequired (true );
// Whether to query the azimuth angle: Yes
Criteria. setbearingrequired (true );
// Whether payment is allowed
Criteria. setcostallowed (true );
// Power requirement: Bottom
Criteria. setpowerrequirement (criteria. power_low );
// Query speed: Yes
Criteria. setspeedrequired (true );

Set the information to be queried to true.

3. Get location

// Obtain the location information in the location provider

Provider = locationmanager. getbestprovider (criteria, true );

4. Set the location listener to update the GPS information in real time when the location changes

Locationmanager. requestlocationupdates (provider, 1000, 0, locationlistener); // The second parameter is the update time (in milliseconds), the second parameter is the update distance, and the last parameter is the listener function.

5. Set listener Functions

// The location listener class monitors the changes in location information.
Private Final locationlistener = new locationlistener ()
{

@ Override
Public void onlocationchanged (location)
{
// Obtain the location through GPS
Updatetonewlocation (location); // displays GPS information
}

@ Override
Public void onproviderdisabled (string arg0)
{

}

@ Override
Public void onproviderenabled (string arg0)
{

}

@ Override
Public void onstatuschanged (string arg0, int arg1, bundle arg2)
{
Updatetonewlocation (null );
}
};

 

6. Display GPS information

Private void updatetonewlocation (location)
{

If (location! = NULL)
{
Bear = location. getbearing (); // degree different from the positive north
Double latitude = location. getlatitude (); // dimension
Double longpolling = location. getlongpolling (); // longitude
Double gpsspeed = location. getspeed (); // speed
Long gpstime = location. gettime (); // time
Date = new date (gpstime );
Dateformat df = new simpledateformat ("yyyy-mm-dd hh: mm: SS ");

Float gpsalt = (float) location. getaltitude (); // altitude
Latitudeview. settext ("" + latitude );
Longitudeview. settext ("" + longpolling );
Speedview. settext ("" + gpsspeed );
Timeview. settext ("" + DF. Format (date ));
Altitudeview. settext ("" + gpsalt );
Bearingview. settext ("" + bear );
}
Else
{
Toast. maketext (this, "unable to obtain geographic information", Toast. length_short). Show ();
}

}

7. Apart from the masterProgramTo obtain GPS information, you must add permissions to the manifest file.

<? XML version = "1.0" encoding = "UTF-8"?>
<Manifest xmlns: Android ="Http://schemas.android.com/apk/res/android"
Package = "zfy. mygps"
Android: versioncode = "1"
Android: versionname = "1.0" type = "codeph" text = "/codeph">
<Uses-SDK Android: minsdkversion = "8"/>

<Application Android: icon = "@ drawable/icon" Android: Label = "@ string/app_name"
Android: debuggable = "true">
<Activity Android: Name = ". mygps"
Android: Label = "@ string/app_name"
Android: screenorientation = "portrait">
<Intent-filter>
<Action Android: Name = "android. Intent. Action. Main"/>
<Category Android: Name = "android. Intent. Category. launcher"/>
</Intent-filter>
</Activity>
</Application>
    <Uses-Permission Android: Name = "android. Permission. access_fine_location"/>
<Uses-Permission Android: Name = "android. Permission. access_location_extra_commands"/>
</Manifest>

 

 

The locationmanager class is also used to obtain satellite information, where addgpsstatuslistener () is used to listen:

Locationmanager. addgpsstatuslistener (statuslistener ). The parameter is a listener function.

 

 

Listener function:

// Add a monitoring satellite
Private Final gpsstatus. Listener statuslistener = new gpsstatus. listener (){
@ Override
Public void ongpsstatuschanged (INT event ){
// Todo auto-generated method stub
// Obtain GPS satellite information
Gpsstatus = locationmanager. getgpsstatus (null );
Switch (Event)
{
Case gpsstatus. gps_event_started:
Break;
// The first positioning time
Case gpsstatus. gps_event_first_fix:
Break;
// Received satellite information
Case gpsstatus. gps_event_satellite_status:

{

// Retrieve all satellites
Allsatellites = gpsstatus. getsatellites ();

// Obtain the satellite Sequence
Iteratorsate = allsatellites. iterator ();

While (iteratorsate. hasnext ())
{
Gpssatellite satellite = iteratorsate. Next ();
Satellite. getazimuth (); // satellite Azimuth
Satellite. getelevation (); // satellite elevation
Satellite. getsnr (); // Signal-to-Noise Ratio

Satellite. getprn (); // pseudo-random number
}

}
Break;
Case gpsstatus. gps_event_stopped:
Break;
}
}
};