如何調試Android GPS跟蹤項目？

Question

我已經發布了一個問題： 如果到達特定位置或大約 20 米，如何跟蹤 GPS？ 從那以后，我學會了如何開始，並創建了一個代碼來跟蹤。

活動：

import java.text.DecimalFormat;
import java.text.NumberFormat;

import android.app.Activity;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.SharedPreferences;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class ProxAlertActivity extends Activity {

    private static final long MINIMUM_DISTANCECHANGE_FOR_UPDATE = 1; // in Meters
    private static final long MINIMUM_TIME_BETWEEN_UPDATE = 1000; // in Milliseconds

    private static final long POINT_RADIUS = 500; // in Meters
    private static final long PROX_ALERT_EXPIRATION = -1; 

    private static final String POINT_LATITUDE_KEY = "POINT_LATITUDE_KEY";
    private static final String POINT_LONGITUDE_KEY = "POINT_LONGITUDE_KEY";

    private static final String PROX_ALERT_INTENT = "com.javacodegeeks.android.lbs.ProximityAlert";

    private static final NumberFormat nf = new DecimalFormat("##.########");

    private LocationManager locationManager;

    private EditText latitudeEditText;
    private EditText longitudeEditText;
    private Button findCoordinatesButton;
    private Button savePointButton;

    @Override
    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);

        locationManager.requestLocationUpdates(
                        LocationManager.GPS_PROVIDER, 
                        MINIMUM_TIME_BETWEEN_UPDATE, 
                        MINIMUM_DISTANCECHANGE_FOR_UPDATE,
                        new MyLocationListener()
        );

        latitudeEditText = (EditText) findViewById(R.id.point_latitude);
        latitudeEditText.setText("13.030729");

        longitudeEditText = (EditText) findViewById(R.id.point_longitude);
        longitudeEditText.setText("80.208975");

        findCoordinatesButton = (Button) findViewById(R.id.find_coordinates_button);
        findCoordinatesButton.setVisibility(View.GONE);

        savePointButton = (Button) findViewById(R.id.save_point_button);

        findCoordinatesButton.setOnClickListener(new OnClickListener() {            
            @Override
            public void onClick(View v) {
                populateCoordinatesFromLastKnownLocation();
            }
        });

        savePointButton.setOnClickListener(new OnClickListener() {          
            @Override
            public void onClick(View v) {
                saveProximityAlertPoint();
            }
        });

    }

    private void saveProximityAlertPoint() {
        Location location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
        if (location==null) {
            Toast.makeText(this, "No last known location. Aborting...", Toast.LENGTH_LONG).show();
            return;
        }
        saveCoordinatesInPreferences((float)location.getLatitude(), (float)location.getLongitude());
        addProximityAlert(location.getLatitude(), location.getLongitude());

    }

    private void addProximityAlert(double latitude, double longitude) {

        Intent intent = new Intent(PROX_ALERT_INTENT);
        PendingIntent proximityIntent = PendingIntent.getBroadcast(this, 0, intent, 0);

        locationManager.addProximityAlert(
            latitude, // the latitude of the central point of the alert region
            longitude, // the longitude of the central point of the alert region
            POINT_RADIUS, // the radius of the central point of the alert region, in meters
            PROX_ALERT_EXPIRATION, // time for this proximity alert, in milliseconds, or -1 to indicate no expiration 
            proximityIntent // will be used to generate an Intent to fire when entry to or exit from the alert region is detected
       );

       IntentFilter filter = new IntentFilter(PROX_ALERT_INTENT);  
       registerReceiver(new ProximityIntentReceiver(), filter);

    }

    private void populateCoordinatesFromLastKnownLocation() {
        Location location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
        if (location!=null) {
            latitudeEditText.setText(nf.format(location.getLatitude()));
            longitudeEditText.setText(nf.format(location.getLongitude()));
        }
    }

    private void saveCoordinatesInPreferences(float latitude, float longitude) {
        SharedPreferences prefs = this.getSharedPreferences(getClass().getSimpleName(), Context.MODE_PRIVATE);
        SharedPreferences.Editor prefsEditor = prefs.edit();
        prefsEditor.putFloat(POINT_LATITUDE_KEY, latitude);
        prefsEditor.putFloat(POINT_LONGITUDE_KEY, longitude);
        prefsEditor.commit();
    }

    private Location retrievelocationFromPreferences() {
        SharedPreferences prefs = this.getSharedPreferences(getClass().getSimpleName(), Context.MODE_PRIVATE);
        Location location = new Location("POINT_LOCATION");
        location.setLatitude(prefs.getFloat(POINT_LATITUDE_KEY, 0));
        location.setLongitude(prefs.getFloat(POINT_LONGITUDE_KEY, 0));
        return location;
    }

    public class MyLocationListener implements LocationListener {
        public void onLocationChanged(Location location) {
            Location pointLocation = retrievelocationFromPreferences();
            float distance = location.distanceTo(pointLocation);
            Toast.makeText(ProxAlertActivity.this, 
                    "Distance from Point:"+distance, Toast.LENGTH_SHORT).show();

        }
        public void onStatusChanged(String s, int i, Bundle b) {            
        }
        public void onProviderDisabled(String s) {
        }
        public void onProviderEnabled(String s) {           
        }
    }

}

播送：

import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.graphics.Color;
import android.location.LocationManager;
import android.util.Log;

public class ProximityIntentReceiver extends BroadcastReceiver {

    private static final int NOTIFICATION_ID = 1000;

    @SuppressWarnings("deprecation")
    @Override
    public void onReceive(Context context, Intent intent) {

        String key = LocationManager.KEY_PROXIMITY_ENTERING;

        Boolean entering = intent.getBooleanExtra(key, false);

        if (entering) {
            Log.d(getClass().getSimpleName(), "entering");
        }
        else {
            Log.d(getClass().getSimpleName(), "exiting");
        }

        NotificationManager notificationManager = 
            (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);

        PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, null, 0);       

        Notification notification = createNotification();
        notification.setLatestEventInfo(context, "Proximity Alert!", "You are near your point of interest.", pendingIntent);

        notificationManager.notify(NOTIFICATION_ID, notification);

    }

    private Notification createNotification() {
        Notification notification = new Notification();

        notification.icon = R.drawable.ic_menu_notifications;
        notification.when = System.currentTimeMillis();

        notification.flags |= Notification.FLAG_AUTO_CANCEL;
        notification.flags |= Notification.FLAG_SHOW_LIGHTS;

        notification.defaults |= Notification.DEFAULT_VIBRATE;
        notification.defaults |= Notification.DEFAULT_LIGHTS;

        notification.ledARGB = Color.WHITE;
        notification.ledOnMS = 1500;
        notification.ledOffMS = 1500;

        return notification;
    }

}

顯現：

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.javacodegeeks.android.lbs"
      android:versionCode="1"
      android:versionName="1.0">

    <application android:icon="@drawable/icon" android:label="@string/app_name">

        <activity android:name=".ProxAlertActivity"
                  android:label="MyTrack">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>     

    </application>

    <uses-sdk android:minSdkVersion="3" />

    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION" /> 
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.VIBRATE" />

</manifest> 

我給出了一個靜態位置，通過進入 500 米半徑，我想它會得到警報。 開始這個之后，我走了1000多米，然后開始返回。

但直到我到達我的位置，我才得到任何警報。

Answer 1

使用 Google Services Location API 獲取位置。 有時 LocationManager 類在提供位置時會產生問題。

代碼如下..

在清單中添加這些權限..

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

在清單文件中的應用程序標簽下添加以下代碼..

<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />

Java代碼在這里..

package com.example.location_test;

import android.app.Activity;

import android.location.Location;
import android.os.Bundle;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GooglePlayServicesClient;
import com.google.android.gms.location.LocationClient;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.location.LocationRequest;

public class Activity1 extends Activity implements
        GooglePlayServicesClient.ConnectionCallbacks,
        GooglePlayServicesClient.OnConnectionFailedListener, LocationListener {

    EditText e1, e2;
    Button b;
    LocationClient mLocationClient;
    Location mCurrentLocation;
    LocationRequest mLocationRequest;

    // Milliseconds per second
    private static final int MILLISECONDS_PER_SECOND = 1000;
    // Update frequency in seconds
    public static final int UPDATE_INTERVAL_IN_SECONDS = 5;
    // Update frequency in milliseconds
    private static final long UPDATE_INTERVAL = MILLISECONDS_PER_SECOND
            * UPDATE_INTERVAL_IN_SECONDS;
    // The fastest update frequency, in seconds
    private static final int FASTEST_INTERVAL_IN_SECONDS = 1;
    // A fast frequency ceiling in milliseconds
    private static final long FASTEST_INTERVAL = MILLISECONDS_PER_SECOND
            * FASTEST_INTERVAL_IN_SECONDS;
    private static final String PROVIDER = "flp";
    private static final float ACCURACY = 3.0f;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity1);

        b = (Button) findViewById(R.id.b);
        e1 = (EditText) findViewById(R.id.e1);
        e2 = (EditText) findViewById(R.id.e2);

        try {
            // Create the LocationRequest object
            mLocationRequest = LocationRequest.create();
            // Use high accuracy
            mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
            // Set the update interval to 5 seconds
            mLocationRequest.setInterval(UPDATE_INTERVAL);
            // Set the fastest update interval to 1 second
            mLocationRequest.setFastestInterval(FASTEST_INTERVAL);

            mLocationClient = new LocationClient(Activity1.this,
                    Activity1.this, Activity1.this);
            mLocationClient.connect();
            // mLocationClient.setMockMode(true);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    @Override
    public void onConnectionFailed(ConnectionResult arg0) {
        // TODO Auto-generated method stub
        Toast.makeText(this, "Connection Failed.", Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onConnected(Bundle arg0) {
        // TODO Auto-generated method stub
        Toast.makeText(this, "Connected", Toast.LENGTH_SHORT).show();
        mLocationClient.requestLocationUpdates(mLocationRequest, this);
    }

    @Override
    public void onDisconnected() {
        // TODO Auto-generated method stub
        Toast.makeText(this, "Connection Disconnected.", Toast.LENGTH_SHORT)
                .show();
    }

    @Override
    public void onLocationChanged(Location location) {
        // TODO Auto-generated method stub
        String msg = "Updated Location: "
                + Double.toString(location.getLatitude()) + ","
                + Double.toString(location.getLongitude());
        Toast.makeText(this, msg, Toast.LENGTH_SHORT).show();
    }
}