Android 位置未在真实设备中显示
Posted
技术标签:
【中文标题】Android 位置未在真实设备中显示【英文标题】:Android location not shown in real device 【发布时间】:2014-02-21 05:24:47 【问题描述】:我正在创建一个应用程序来查找用户的当前位置。 我提到了这个链接 What is the simplest and most robust way to get the user's current location on android?
创建我的应用程序。 我的问题我对这两个提供者都进行了尝试,但它没有检测到任何提供者,结果总是 location=null 返回。 为什么会出现这个问题以及如何在手机中获取位置。? 提前谢谢...
我的代码放在这里 这是 MyLocation.java 类
package com.example.locationupadates;
import java.util.Timer;
import java.util.TimerTask;
import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.util.Log;
public class MyLocation
Timer timer1;
LocationManager lm;
LocationResult locationResult;
boolean gps_enabled=false;
boolean network_enabled=false;
public boolean getLocation(Context context, LocationResult result)
//I use LocationResult callback class to pass location value from MyLocation to user code.
locationResult=result;
if(lm==null)
lm = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
//exceptions will be thrown if provider is not permitted.
trygps_enabled=lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
Log.v("Ansar",""+"Network Enabled");catch(Exception ex)
trynetwork_enabled=lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
Log.v("Ansar",""+"Network Enabled");catch(Exception ex)
//don't start listeners if no provider is enabled
if(!gps_enabled && !network_enabled)
Log.v("Ansar",""+"Not anything Enabled");
return false;
if(gps_enabled)
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListenerGps);
Log.v("Ansar",""+"Location Listener Gps");
if(network_enabled)
lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListenerNetwork);
Log.v("Ansar",""+"Location Listener Network");
timer1=new Timer();
timer1.schedule(new GetLastLocation(), 20000);
return true;
LocationListener locationListenerGps = new LocationListener()
public void onLocationChanged(Location location)
timer1.cancel();
locationResult.gotLocation(location);
lm.removeUpdates(this);
lm.removeUpdates(locationListenerNetwork);
Log.v("Ansar",""+location.getLongitude());
public void onProviderDisabled(String provider)
public void onProviderEnabled(String provider)
public void onStatusChanged(String provider, int status, Bundle extras)
;
LocationListener locationListenerNetwork = new LocationListener()
public void onLocationChanged(Location location)
timer1.cancel();
locationResult.gotLocation(location);
lm.removeUpdates(this);
lm.removeUpdates(locationListenerGps);
public void onProviderDisabled(String provider)
public void onProviderEnabled(String provider)
public void onStatusChanged(String provider, int status, Bundle extras)
;
class GetLastLocation extends TimerTask
@Override
public void run()
lm.removeUpdates(locationListenerGps);
lm.removeUpdates(locationListenerNetwork);
Location net_loc=null, gps_loc=null;
if(gps_enabled)
gps_loc=lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if(network_enabled)
net_loc=lm.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
//if there are both values use the latest one
if(gps_loc!=null && net_loc!=null)
if(gps_loc.getTime()>net_loc.getTime())
locationResult.gotLocation(gps_loc);
else
locationResult.gotLocation(net_loc);
return;
if(gps_loc!=null)
locationResult.gotLocation(gps_loc);
return;
if(net_loc!=null)
locationResult.gotLocation(net_loc);
return;
locationResult.gotLocation(null);
public static abstract class LocationResult
public abstract void gotLocation(Location location);
MainActivity.java
package com.example.locationupadates;
import android.app.Activity;
import android.location.Location;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.widget.TextView;
import com.example.locationupadates.MyLocation.LocationResult;
public class MainActivity extends Activity
TextView tv;
@Override
protected void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv=(TextView) findViewById(R.id.tv);
Log.d("Ansar",""+"oncreate");
LocationResult locationResult = new LocationResult()
@Override
public void gotLocation(Location location)
Log.v("Ansar",""+location.getLongitude());
tv.setText("location:"+location+"latitude: "+location.getLatitude()+"longitude "+location.getLongitude());
;
MyLocation myLocation = new MyLocation();
myLocation.getLocation(this, locationResult);
@Override
public boolean onCreateOptionsMenu(Menu menu)
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
Manifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.locationupadates"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="10"
android:targetSdkVersion="18" />
<uses-permission android:name="android.permission.INTERNET"/>
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.locationupadates.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>
异常
02-21 11:39:05.963: W/dalvikvm(18909): threadid=11: thread exiting with uncaught exception (group=0x410e4390)
02-21 11:39:05.963: E/AndroidRuntime(18909): FATAL EXCEPTION: Timer-0
02-21 11:39:05.963: E/AndroidRuntime(18909): java.lang.NullPointerException
02-21 11:39:05.963: E/AndroidRuntime(18909): at com.example.locationupadates.MainActivity$1.gotLocation(MainActivity.java:23)
02-21 11:39:05.963: E/AndroidRuntime(18909): at com.example.locationupadates.MyLocation$GetLastLocation.run(MyLocation.java:102)
02-21 11:39:05.963: E/AndroidRuntime(18909): at java.util.Timer$TimerImpl.run(Timer.java:284)
02-21 11:39:05.963: W/dalvikvm(18909): threadid=11: thread exiting with uncaught exception (group=0x410e4390)
02-21 11:39:05.963: E/AndroidRuntime(18909): FATAL EXCEPTION: Timer-0
02-21 11:39:05.963: E/AndroidRuntime(18909): java.lang.NullPointerException
02-21 11:39:05.963: E/AndroidRuntime(18909): at com.example.locationupadates.MainActivity$1.gotLocation(MainActivity.java:23)
02-21 11:39:05.963: E/AndroidRuntime(18909): at com.example.locationupadates.MyLocation$GetLastLocation.run(MyLocation.java:102)
02-21 11:39:05.963: E/AndroidRuntime(18909): at java.util.Timer$TimerImpl.run(Timer.java:284)
【问题讨论】:
你能用 manifest.xml 和错误日志粘贴你的代码吗? 当我在我的设备三星中运行你的代码时,它完美地给了我想要的结果。我对提供者都进行了尝试,结果是肯定的,而不是错误。Only the original thread that created a view hierarchy can touch its views
通常当您尝试从线程访问任何视图时会发生此错误。签入您的代码。将 Text 设置为 Textview 时出现此错误,对吗?
我在 HTC 设备上见过这类异常最多。
我在我的 Samsung S2、Android 4.1.2 中运行您的代码,它运行良好 :)
【参考方案1】:
试试下面的课……我想对你有帮助……
添加主要活动...
GPSTracker gps = new GPSTracker(ActivityNearBy.this);
if (gps.canGetLocation())
latitude = gps.getLatitude();
longitude = gps.getLongitude();
GPS 服务
public class GPSTracker extends Service implements LocationListener
private final Context mContext;
// flag for GPS status
boolean isGPSEnabled = false;
// flag for network status
boolean isNetworkEnabled = false;
// flag for GPS status
boolean canGetLocation = false;
Location location; // location
double latitude; // latitude
double longitude; // longitude
// The minimum distance to change Updates in meters
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; // 10 meters
// The minimum time between updates in milliseconds
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1; // 1 minute
// Declaring a Location Manager
protected LocationManager locationManager;
public GPSTracker(Context context)
this.mContext = context;
getLocation();
public Location getLocation()
try
locationManager = (LocationManager) mContext.getSystemService(LOCATION_SERVICE);
// getting GPS status
isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
// getting network status
isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!isGPSEnabled && !isNetworkEnabled)
// no network provider is enabled
else
this.canGetLocation = true;
if (isNetworkEnabled)
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("Network", "Network");
if (locationManager != null)
location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (location != null)
latitude = location.getLatitude();
longitude = location.getLongitude();
// if GPS Enabled get lat/long using GPS Services
if (isGPSEnabled)
if (location == null)
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("GPS Enabled", "GPS Enabled");
if (locationManager != null)
location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null)
latitude = location.getLatitude();
longitude = location.getLongitude();
catch (Exception e)
e.printStackTrace();
return location;
/**
* Stop using GPS listener Calling this function will stop using GPS in your
* app
* */
public void stopUsingGPS()
if (locationManager != null)
locationManager.removeUpdates(GPSTracker.this);
/**
* Function to get latitude
* */
public double getLatitude()
if (location != null)
latitude = location.getLatitude();
// return latitude
return latitude;
/**
* Function to get longitude
* */
public double getLongitude()
if (location != null)
longitude = location.getLongitude();
// return longitude
return longitude;
/**
* Function to check GPS/wifi enabled
*
* @return boolean
* */
public boolean canGetLocation()
return this.canGetLocation;
/**
* Function to show settings alert dialog On pressing Settings button will
* lauch Settings Options
* */
public void showSettingsAlert()
AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);
// Setting Dialog Title
alertDialog.setTitle("GPS is settings");
// Setting Dialog Message
alertDialog.setMessage("GPS is not enabled. Do you want to go to settings menu?");
// On pressing Settings button
alertDialog.setPositiveButton("Settings",new DialogInterface.OnClickListener()
public void onClick(DialogInterface dialog, int which)
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
mContext.startActivity(intent);
);
// on pressing cancel button
alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener()
public void onClick(DialogInterface dialog, int which)
dialog.cancel();
);
// Showing Alert Message
alertDialog.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 onStatusChanged(String provider, int status, Bundle extras)
// TODO Auto-generated method stub
public void onProviderDisabled(String provider)
// TODO Auto-generated method stub
@Override
public void onRebind(Intent intent)
// TODO Auto-generated method stub
super.onRebind(intent);
@Override
public boolean onUnbind(Intent intent)
// TODO Auto-generated method stub
return super.onUnbind(intent);
public void onProviderEnabled(String provider)
// TODO Auto-generated method stub
更新 manifest.xml
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_LOCATION_EXTRA_COMMANDS" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
【讨论】:
我试过这个代码。实际上这段代码在模拟器上运行良好,但在设备上却不行。 请更新 Play 商店库并确保 GPS 开启或关闭。 此代码在 Play 商店(cqpon 应用程序)上的实时应用程序中运行良好以上是关于Android 位置未在真实设备中显示的主要内容,如果未能解决你的问题,请参考以下文章