android GPS程序沒有錯誤，但沒有運行，'不幸的應用程序停止working'message來模擬器

Question

嗨，我想做一個Android程序的GPS檢測。沒有錯誤即將到來但我面臨的消息「不幸的是，應用程序已停止「，沒有任何事情發生。請您幫我出

我對Gpstracker.java

代碼

package com.example.gpstracking; 

import android.app.AlertDialog; 
import android.app.Service; 
import android.content. Context; 
import android.content.DialogInterface; 
import android.content.Intent; 
import android.location.Location; 
import android.location.LocationListener; 
import android.location.LocationManager; 
import android.os.Bundle; 
import android.os.IBinder; 
import android.provider.Settings; 
import android.util.Log; 

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; 
      // First get location from Network Provider 
      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 void onLocationChanged(Location location) { 
} 

@Override 
public void onProviderDisabled(String provider) { 
} 

@Override 
public void onProviderEnabled(String provider) { 
} 

@Override 
public void onStatusChanged(String provider, int status, Bundle extras) { 
} 

@Override 
public IBinder onBind(Intent arg0) { 
    return null; 
} 


} 

代碼AndroidGPSTrackingActivity.java這是在同一個包

package com.example.gpstracking; 

import android.R; 
import android.app.Activity; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.Button; 
import android.widget.Toast; 

public class AndroidGPSTrackingActivity extends Activity { 

Button btnShowLocation; 

// GPSTracker class 
GpsTracker gps; 

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_list_item); 

    btnShowLocation = (Button) findViewById(R.id.button1); 

    // show location button click event 
    btnShowLocation.setOnClickListener(new View.OnClickListener() { 

     @Override 
     public void onClick(View arg0) { 
      // create class object 
      gps = new GpsTracker(AndroidGPSTrackingActivity.this); 

      // check if GPS enabled 
      if(gps.canGetLocation()){ 

       double latitude = gps.getLatitude(); 
       double longitude = gps.getLongitude(); 

       // \n is for new line 
       Toast.makeText(getApplicationContext(), "Your Location is - \nLat: " + latitude + "\nLong: " + longitude, Toast.LENGTH_LONG).show(); 
      }else{ 
       // can't get location 
       // GPS or Network is not enabled 
       // Ask user to enable GPS/network in settings 
       gps.showSettingsAlert(); 
      } 

     } 
    }); 
} 


} 

GPSTrackermanifest.xml文件

<?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
package="com.example.gpstracking" 
android:versionCode="1" 
android:versionName="1.0" > 

<uses-sdk android:minSdkVersion="8" /> 

<application 
    android:icon="@drawable/ic_launcher" 
    android:label="@string/app_name" > 
    <activity 
     android:name=".AndroidGPSTrackingActivity" 
     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> 

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> 
<uses-permission android:name="android.permission.INTERNET" /> 

</manifest> 

Answer 1

代碼中有太多錯誤！

1）使用未在清單文件 2中聲明的服務GPSTracker）啓動該服務 3）您必須先註冊地點listeneners 4）你必須使用onLocationChanged獲得新的位置 5）使用onStatusChanged和onLocationChanged獲取GPS狀態