我是android的新手。 我正在研究一个巫婆的android项目我需要使用GPS获取用户的当前位置。 但是我的代码工作不正常。
java代码
package com.example.checkinapp;
import android.app.Activity;
import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.widget.TextView;
public class MainActivity extends Activity
{
TextView textlat;
TextView textlong;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
textlat = (TextView)findViewById(R.id.textlat);
textlong = (TextView)findViewById(R.id.textlong);
LocationManager lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
LocationListener ll = new mylocationlistener();
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, ll);
}
class mylocationlistener implements LocationListener{
@Override
public void onLocationChanged(Location location) {
if(location!=null)
{
double lat = location.getLatitude();
double lng = location.getLongitude();
textlat.setText(Double.toString(lat));
textlong.setText(Double.toString(lng));
}
}
@Override
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onStatusChanged(String provider, int status,
Bundle extras) {
// TODO Auto-generated method stub
}
}
}
activity_main.xml中
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<TextView
android:id="@+id/textlat"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_marginTop="16dp"
android:text=""
android:ems="10">
</TextView>
<TextView
android:id="@+id/textlong"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="25dp"
android:text=""
android:ems="10">
</TextView>
</RelativeLayout>
AndroidMainfest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.checkinapp"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.checkinapp.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
我正在尝试将用户的纬度和经度显示为textview。 但我没有得到结果。 感谢。
答案 0 :(得分：9)
使用此课程获取应用中的当前位置，这对我来说非常有用
/**
* Gps location tracker class
* to get users location and other information related to location
*/
public class GpsLocationTracker extends Service implements LocationListener
{
/**
* context of calling class
*/
private Context mContext;
/**
* flag for gps status
*/
private boolean isGpsEnabled = false;
/**
* flag for network status
*/
private boolean isNetworkEnabled = false;
/**
* flag for gps
*/
private boolean canGetLocation = false;
/**
* location
*/
private Location mLocation;
/**
* latitude
*/
private double mLatitude;
/**
* longitude
*/
private double mLongitude;
/**
* min distance change to get location update
*/
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATE = 10;
/**
* min time for location update
* 60000 = 1min
*/
private static final long MIN_TIME_FOR_UPDATE = 60000;
/**
* location manager
*/
private LocationManager mLocationManager;
/**
* @param mContext constructor of the class
*/
public GpsLocationTracker(Context mContext) {
this.mContext = mContext;
getLocation();
}
/**
* @return location
*/
public Location getLocation() {
try {
mLocationManager = (LocationManager) mContext.getSystemService(LOCATION_SERVICE);
/*getting status of the gps*/
isGpsEnabled = mLocationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
/*getting status of network provider*/
isNetworkEnabled = mLocationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!isGpsEnabled && !isNetworkEnabled) {
/*no location provider enabled*/
} else {
this.canGetLocation = true;
/*getting location from network provider*/
if (isNetworkEnabled) {
mLocationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, MIN_TIME_FOR_UPDATE, MIN_DISTANCE_CHANGE_FOR_UPDATE, this);
if (mLocationManager != null) {
mLocation = mLocationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (mLocation != null) {
mLatitude = mLocation.getLatitude();
mLongitude = mLocation.getLongitude();
}
}
/*if gps is enabled then get location using gps*/
if (isGpsEnabled) {
if (mLocation == null) {
mLocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, MIN_TIME_FOR_UPDATE, MIN_DISTANCE_CHANGE_FOR_UPDATE, this);
if (mLocationManager != null) {
mLocation = mLocationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (mLocation != null) {
mLatitude = mLocation.getLatitude();
mLongitude = mLocation.getLongitude();
}
}
}
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
return mLocation;
}
/**
* call this function to stop using gps in your application
*/
public void stopUsingGps() {
if (mLocationManager != null) {
mLocationManager.removeUpdates(GpsLocationTracker.this);
}
}
/**
* @return latitude
* <p/>
* function to get latitude
*/
public double getLatitude() {
if (mLocation != null) {
mLatitude = mLocation.getLatitude();
}
return mLatitude;
}
/**
* @return longitude
* function to get longitude
*/
public double getLongitude() {
if (mLocation != null) {
mLongitude = mLocation.getLongitude();
}
return mLongitude;
}
/**
* @return to check gps or wifi is enabled or not
*/
public boolean canGetLocation() {
return this.canGetLocation;
}
/**
* function to prompt user to open
* settings to enable gps
*/
public void showSettingsAlert() {
AlertDialog.Builder mAlertDialog = new AlertDialog.Builder(new ContextThemeWrapper(mContext, R.style.AppTheme));
mAlertDialog.setTitle("Gps Disabled");
mAlertDialog.setMessage("gps is not enabled . do you want to enable ?");
mAlertDialog.setPositiveButton("settings", new OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
Intent mIntent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
mContext.startActivity(mIntent);
}
});
mAlertDialog.setNegativeButton("cancle", new OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
dialog.cancel();
}
});
final AlertDialog mcreateDialog = mAlertDialog.create();
mcreateDialog.show();
}
@Override
public IBinder onBind(Intent arg0) {
// TODO Auto-generated method stub
return null;
}
public void onLocationChanged(Location location) {
// TODO Auto-generated method stub
}
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
}
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
}
＆安培;以这种方式使用
GpsLocationTracker mGpsLocationTracker = new GpsLocationTracker(YourActivity.this);
/**
* Set GPS Location fetched address
*/
if (mGpsLocationTracker.canGetLocation())
{
latitude = mGpsLocationTracker.getLatitude();
longitude = mGpsLocationTracker.getLongitude();
Log.i(TAG, String.format("latitude: %s", latitude));
Log.i(TAG, String.format("longitude: %s", longitude));
}
else
{
mGpsLocationTracker.showSettingsAlert();
}
＆安培;不要忘记在Manifest.xml中设置权限
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
答案 1 :(得分：0)
试试这个，
LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
Criteria criteria = new Criteria();
String provider = locationManager.getBestProvider(criteria,
true);
Location location = locationManager
.getLastKnownLocation(provider);
if (location != null) {
onLocationChanged(location);
}
// updates location 30seconds once
locationManager
.requestLocationUpdates(provider, 30000, 0, this);
答案 2 :(得分：0)
使用commonsware库..比其他代码稳定得多...你只需要从这里下载库
https://github.com/commonsguy/downloads/blob/master/CWAC-LocationPoller.jar
这是代码
public class LocationReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
Log.i(getClass().getSimpleName(), "Received intent for " + intent.getComponent().flattenToShortString());
try {
Bundle b=intent.getExtras();
LocationPollerResult locationResult = new LocationPollerResult(b);
Location loc=locationResult.getLocation();
String msg;
if (loc==null) {
loc=locationResult.getLastKnownLocation();
if (loc==null) {
msg=locationResult.getError();
}
else {
msg="TIMEOUT, lastKnown="+loc.toString();
}
}
else {
msg=loc.toString();
}
if (msg==null) {
msg="Invalid broadcast received!";
}
Log.i(getClass().getSimpleName(), "received location: " + msg);
}
catch (Exception e) {
Log.e(getClass().getName(), e.getMessage());
}
}
答案 3 :(得分：0)
这两种方法可以获取用户的位置
如果您使用GPS_PROVIDER，它只适用于室外，准确性很好。
String locationProvider = LocationManager.NETWORK_PROVIDER;
String locationProvider = LocationManager.GPS_PROVIDER;
除了Manifest中所需的权限
答案 4 :(得分：0)
LocationManager manager = (LocationManager) this .getSystemService(Context.LOCATION_SERVICE);
Location loc = manager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
Toast.makeText( getApplicationContext(),"My current location is: " + "Latitud =" +
loc.getLatitude() + "Longitud = " + loc.getLongitude(),Toast.LENGTH_SHORT).show();