Android中使用GoogleMap的地理位置服务

写在前面：android中使用地理位置功能，可以借助Google给我们提供的框架，要是有地理位置功能，你需要引用Google Play Services，请在sdk manager中下载。
如果你还要使用地图功能，请到google官网申请api-key

如果要看官方例子可以到https://github.com/googlesamples/android-play-location.git下载

使用Google地理服务都需要如下，

引用Google Play Services

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

声明权限

定位功能涉及到权限，下面2选1；

ACCESS_COARSE_LOCATION 粗略位置
或者ACCESS_FINE_LOCATION精确位置

1.基本使用，获取上一次的位置。

   /**
     * 构建位置服务客户端对象
     */
    protected synchronized void buildGoogleApiClient() {
        mGoogleApiClient = new GoogleApiClient.Builder(this)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API)
                .build();
    }

    /**
     *在onStart中使用客户端连接GooglePlay Service
     */
    @Override
    protected void onStart() {
        super.onStart();
        mGoogleApiClient.connect();
    }

    /**
     * 离开界面时，断开连接
     */
    @Override
    protected void onStop() {
        super.onStop();
        if (mGoogleApiClient.isConnected()) {
            mGoogleApiClient.disconnect();
        }
    }

    /**
     * 连接GooglePlay Service成功后，可以在回调方法中获取上一次的位置
     */
    @Override
    public void onConnected(Bundle connectionHint) {
        // Provides a simple way of getting a device's location and is well suited for
        // applications that do not require a fine-grained location and that do not need location
        // updates. Gets the best and most recent location currently available, which may be null
        // in rare cases when a location is not available.
        mLastLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
        if (mLastLocation != null) {
            mLatitudeText.setText(String.format("%s: %f", mLatitudeLabel,
                    mLastLocation.getLatitude()));
            mLongitudeText.setText(String.format("%s: %f", mLongitudeLabel,
                    mLastLocation.getLongitude()));
        } else {
            Toast.makeText(this, R.string.no_location_detected, Toast.LENGTH_LONG).show();
        }
    }

    /**
     * 连接失败
     * @param result
     */
    @Override
    public void onConnectionFailed(ConnectionResult result) {
        // Refer to the javadoc for ConnectionResult to see what error codes might be returned in
        // onConnectionFailed.
        Log.i(TAG, "Connection failed: ConnectionResult.getErrorCode() = " + result.getErrorCode());
    }


    /**
     * 连接被暂停了，重新连接
     * @param cause
     */
    @Override
    public void onConnectionSuspended(int cause) {
        // The connection to Google Play services was lost for some reason. We call connect() to
        // attempt to re-establish the connection.
        Log.i(TAG, "Connection suspended");
        mGoogleApiClient.connect();
    }

2.实时刷新最新位置，获取最新位置信息； 

连接成功后，在回调方法中执行位置监听；首先配置位置请求参数，创建位置请求对象，后调用监听。

　　 /**
     * The desired interval for location updates. Inexact. Updates may be more or less frequent.
     */
    public static final long UPDATE_INTERVAL_IN_MILLISECONDS = 10000;

    /**
     * The fastest rate for active location updates. Exact. Updates will never be more frequent
     * than this value.
     */
    public static final long FASTEST_UPDATE_INTERVAL_IN_MILLISECONDS =
            UPDATE_INTERVAL_IN_MILLISECONDS / 2;

    /**
     * 创建位置请求对象mLocationRequest，封装监听参数
     */
    protected void createLocationRequest() {
        mLocationRequest = new LocationRequest();

        // Sets the desired interval for active location updates. This interval is
        // inexact. You may not receive updates at all if no location sources are available, or
        // you may receive them slower than requested. You may also receive updates faster than
        // requested if other applications are requesting location at a faster interval.
        mLocationRequest.setInterval(UPDATE_INTERVAL_IN_MILLISECONDS);

        // Sets the fastest rate for active location updates. This interval is exact, and your
        // application will never receive updates faster than this value.
        mLocationRequest.setFastestInterval(FASTEST_UPDATE_INTERVAL_IN_MILLISECONDS);

        mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
    }

    /**
     * 开始监听位置变化
     */
    protected void startLocationUpdates() {
        // The final argument to {@code requestLocationUpdates()} is a LocationListener
        // (http://developer.android.com/reference/com/google/android/gms/location/LocationListener.html).
        LocationServices.FusedLocationApi.requestLocationUpdates(
                mGoogleApiClient, mLocationRequest, this);
    }

    /**
     * 回调方法中获取到改变的最新位置
     */
    @Override
    public void onLocationChanged(Location location) {
        mCurrentLocation = location;
        mLastUpdateTime = DateFormat.getTimeInstance().format(new Date());
        updateUI();
        Toast.makeText(this, getResources().getString(R.string.location_updated_message),
                Toast.LENGTH_SHORT).show();
    }

3.获取到位置的经纬度后，可以将其转为地址信息。

这里使用开启服务来解析经纬度。

       if (mLastLocation != null) {
            // Determine whether a Geocoder is available.
            if (!Geocoder.isPresent()) {
                Toast.makeText(this, R.string.no_geocoder_available, Toast.LENGTH_LONG).show();
                return;
            }
            // It is possible that the user presses the button to get the address before the
            // GoogleApiClient object successfully connects. In such a case, mAddressRequested
            // is set to true, but no attempt is made to fetch the address (see
            // fetchAddressButtonHandler()) . Instead, we start the intent service here if the
            // user has requested an address, since we now have a connection to GoogleApiClient.
            if (mAddressRequested) {
                startIntentService(); //开启服务解析经纬度
            }
        }

使用IntentService

public class FetchAddressIntentService extends IntentService {
    private static final String TAG = "FetchAddressIS";

    /**
     * The receiver where results are forwarded from this service.
     */
    protected ResultReceiver mReceiver;

    /**
     * This constructor is required, and calls the super IntentService(String)
     * constructor with the name for a worker thread.
     */
    public FetchAddressIntentService() {
        // Use the TAG to name the worker thread.
        super(TAG);
    }

    /**
     * Tries to get the location address using a Geocoder. If successful, sends an address to a
     * result receiver. If unsuccessful, sends an error message instead.
     * Note: We define a {@link android.os.ResultReceiver} in * MainActivity to process content
     * sent from this service.
     *
     * This service calls this method from the default worker thread with the intent that started
     * the service. When this method returns, the service automatically stops.
     */
    @Override
    protected void onHandleIntent(Intent intent) {
        String errorMessage = "";

        mReceiver = intent.getParcelableExtra(Constants.RECEIVER);

        // Check if receiver was properly registered.
        if (mReceiver == null) {
            Log.wtf(TAG, "No receiver received. There is nowhere to send the results.");
            return;
        }

        // Get the location passed to this service through an extra.
        Location location = intent.getParcelableExtra(Constants.LOCATION_DATA_EXTRA);

        // Make sure that the location data was really sent over through an extra. If it wasn't,
        // send an error error message and return.
        if (location == null) {
            errorMessage = getString(R.string.no_location_data_provided);
            Log.wtf(TAG, errorMessage);
            deliverResultToReceiver(Constants.FAILURE_RESULT, errorMessage);
            return;
        }

        // Errors could still arise from using the Geocoder (for example, if there is no
        // connectivity, or if the Geocoder is given illegal location data). Or, the Geocoder may
        // simply not have an address for a location. In all these cases, we communicate with the
        // receiver using a resultCode indicating failure. If an address is found, we use a
        // resultCode indicating success.

        // The Geocoder used in this sample. The Geocoder's responses are localized for the given
        // Locale, which represents a specific geographical or linguistic region. Locales are used
        // to alter the presentation of information such as numbers or dates to suit the conventions
        // in the region they describe.
        Geocoder geocoder = new Geocoder(this, Locale.getDefault());

        // Address found using the Geocoder.
        List<Address> addresses = null;

        try {
            // Using getFromLocation() returns an array of Addresses for the area immediately
            // surrounding the given latitude and longitude. The results are a best guess and are
            // not guaranteed to be accurate.
            addresses = geocoder.getFromLocation(
                    location.getLatitude(),
                    location.getLongitude(),
                    // In this sample, we get just a single address.
                    1);
        } catch (IOException ioException) {
            // Catch network or other I/O problems.
            errorMessage = getString(R.string.service_not_available);
            Log.e(TAG, errorMessage, ioException);
        } catch (IllegalArgumentException illegalArgumentException) {
            // Catch invalid latitude or longitude values.
            errorMessage = getString(R.string.invalid_lat_long_used);
            Log.e(TAG, errorMessage + ". " +
                    "Latitude = " + location.getLatitude() +
                    ", Longitude = " + location.getLongitude(), illegalArgumentException);
        }

        // Handle case where no address was found.
        if (addresses == null || addresses.size()  == 0) {
            if (errorMessage.isEmpty()) {
                errorMessage = getString(R.string.no_address_found);
                Log.e(TAG, errorMessage);
            }
            deliverResultToReceiver(Constants.FAILURE_RESULT, errorMessage);
        } else {
            Address address = addresses.get(0);
            ArrayList<String> addressFragments = new ArrayList<String>();

            // Fetch the address lines using {@code getAddressLine},
            // join them, and send them to the thread. The {@link android.location.address}
            // class provides other options for fetching address details that you may prefer
            // to use. Here are some examples:
            // getLocality() ("Mountain View", for example)
            // getAdminArea() ("CA", for example)
            // getPostalCode() ("94043", for example)
            // getCountryCode() ("US", for example)
            // getCountryName() ("United States", for example)
            for(int i = 0; i < address.getMaxAddressLineIndex(); i++) {
                addressFragments.add(address.getAddressLine(i));
            }
            Log.i(TAG, getString(R.string.address_found));
            deliverResultToReceiver(Constants.SUCCESS_RESULT,
                    TextUtils.join(System.getProperty("line.separator"), addressFragments));
        }
    }

    /**
     * Sends a resultCode and message to the receiver.
     */
    private void deliverResultToReceiver(int resultCode, String message) {
        Bundle bundle = new Bundle();
        bundle.putString(Constants.RESULT_DATA_KEY, message);
        mReceiver.send(resultCode, bundle);
    }
}

将服务声明下

       <service
            android:name=".FetchAddressIntentService"
            android:exported="false"/>

4.使用地理围栏，在进入和退出围栏时有提醒。

    /**
     * Adds geofences, which sets alerts to be notified when the device enters or exits one of the
     * specified geofences. Handles the success or failure results returned by addGeofences().
     */
    public void addGeofencesButtonHandler(View view) {
        if (!mGoogleApiClient.isConnected()) {
            Toast.makeText(this, getString(R.string.not_connected), Toast.LENGTH_SHORT).show();
            return;
        }

        try {
            LocationServices.GeofencingApi.addGeofences(
                    mGoogleApiClient,
                    // The GeofenceRequest object.
                    getGeofencingRequest(),
                    // A pending intent that that is reused when calling removeGeofences(). This
                    // pending intent is used to generate an intent when a matched geofence
                    // transition is observed.
                    getGeofencePendingIntent()
            ).setResultCallback(this); // Result processed in onResult().
        } catch (SecurityException securityException) {
            // Catch exception generated if the app does not use ACCESS_FINE_LOCATION permission.
            logSecurityException(securityException);
        }
    }

   /**
     * Builds and returns a GeofencingRequest. Specifies the list of geofences to be monitored.
     * Also specifies how the geofence notifications are initially triggered.
     */
    private GeofencingRequest getGeofencingRequest() {
        GeofencingRequest.Builder builder = new GeofencingRequest.Builder();

        // The INITIAL_TRIGGER_ENTER flag indicates that geofencing service should trigger a
        // GEOFENCE_TRANSITION_ENTER notification when the geofence is added and if the device
        // is already inside that geofence.
        builder.setInitialTrigger(GeofencingRequest.INITIAL_TRIGGER_ENTER);

        // Add the geofences to be monitored by geofencing service.
        builder.addGeofences(mGeofenceList);

        // Return a GeofencingRequest.
        return builder.build();
    }

  /**
     * Gets a PendingIntent to send with the request to add or remove Geofences. Location Services
     * issues the Intent inside this PendingIntent whenever a geofence transition occurs for the
     * current list of geofences.
     *
     * @return A PendingIntent for the IntentService that handles geofence transitions.
     */
    private PendingIntent getGeofencePendingIntent() {
        // Reuse the PendingIntent if we already have it.
        if (mGeofencePendingIntent != null) {
            return mGeofencePendingIntent;
        }
        Intent intent = new Intent(this, GeofenceTransitionsIntentService.class);
        // We use FLAG_UPDATE_CURRENT so that we get the same pending intent back when calling
        // addGeofences() and removeGeofences().
        return PendingIntent.getService(this, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
    }

创建围栏

    /**
     * This sample hard codes geofence data. A real app might dynamically create geofences based on
     * the user's location.
     */
    public void populateGeofenceList() {
        for (Map.Entry<String, LatLng> entry : Constants.BAY_AREA_LANDMARKS.entrySet()) {

            mGeofenceList.add(new Geofence.Builder()
                    // Set the request ID of the geofence. This is a string to identify this
                    // geofence.
                    .setRequestId(entry.getKey())

                    // Set the circular region of this geofence.
                    .setCircularRegion(
                            entry.getValue().latitude,
                            entry.getValue().longitude,
                            Constants.GEOFENCE_RADIUS_IN_METERS
                    )

                    // Set the expiration duration of the geofence. This geofence gets automatically
                    // removed after this period of time.
                    .setExpirationDuration(Constants.GEOFENCE_EXPIRATION_IN_MILLISECONDS)

                    // Set the transition types of interest. Alerts are only generated for these
                    // transition. We track entry and exit transitions in this sample.
                    .setTransitionTypes(Geofence.GEOFENCE_TRANSITION_ENTER |
                            Geofence.GEOFENCE_TRANSITION_EXIT)

                    // Create the geofence.
                    .build());
        }
    }

删除围栏。

   /**
     * Removes geofences, which stops further notifications when the device enters or exits
     * previously registered geofences.
     */
    public void removeGeofencesButtonHandler(View view) {
        if (!mGoogleApiClient.isConnected()) {
            Toast.makeText(this, getString(R.string.not_connected), Toast.LENGTH_SHORT).show();
            return;
        }
        try {
            // Remove geofences.
            LocationServices.GeofencingApi.removeGeofences(
                    mGoogleApiClient,
                    // This is the same pending intent that was used in addGeofences().
                    getGeofencePendingIntent()
            ).setResultCallback(this); // Result processed in onResult().
        } catch (SecurityException securityException) {
            // Catch exception generated if the app does not use ACCESS_FINE_LOCATION permission.
            logSecurityException(securityException);
        }
    }

创建和删除围栏的回调，

    /**
     * Runs when the result of calling addGeofences() and removeGeofences() becomes available.
     * Either method can complete successfully or with an error.
     *
     * Since this activity implements the {@link ResultCallback} interface, we are required to
     * define this method.
     *
     * @param status The Status returned through a PendingIntent when addGeofences() or
     *               removeGeofences() get called.
     */
    public void onResult(Status status) {
        if (status.isSuccess()) {
            // Update state and save in shared preferences.
            mGeofencesAdded = !mGeofencesAdded;
            SharedPreferences.Editor editor = mSharedPreferences.edit();
            editor.putBoolean(Constants.GEOFENCES_ADDED_KEY, mGeofencesAdded);
            editor.apply();

            // Update the UI. Adding geofences enables the Remove Geofences button, and removing
            // geofences enables the Add Geofences button.
            setButtonsEnabledState();

            Toast.makeText(
                    this,
                    getString(mGeofencesAdded ? R.string.geofences_added :
                            R.string.geofences_removed),
                    Toast.LENGTH_SHORT
            ).show();
        } else {
            // Get the status code for the error and log it using a user-friendly message.
            String errorMessage = GeofenceErrorMessages.getErrorString(this,
                    status.getStatusCode());
            Log.e(TAG, errorMessage);
        }
    }

使用服务来监听这种进出围栏的状态，

 /**
 * Listener for geofence transition changes.
 *
 * Receives geofence transition events from Location Services in the form of an Intent containing
 * the transition type and geofence id(s) that triggered the transition. Creates a notification
 * as the output.
 */
public class GeofenceTransitionsIntentService extends IntentService {

    protected static final String TAG = "GeofenceTransitionsIS";

    /**
     * This constructor is required, and calls the super IntentService(String)
     * constructor with the name for a worker thread.
     */
    public GeofenceTransitionsIntentService() {
        // Use the TAG to name the worker thread.
        super(TAG);
    }

    @Override
    public void onCreate() {
        super.onCreate();
    }

    /**
     * Handles incoming intents.
     * @param intent sent by Location Services. This Intent is provided to Location
     *               Services (inside a PendingIntent) when addGeofences() is called.
     */
    @Override
    protected void onHandleIntent(Intent intent) {
        GeofencingEvent geofencingEvent = GeofencingEvent.fromIntent(intent);
        if (geofencingEvent.hasError()) {
            String errorMessage = GeofenceErrorMessages.getErrorString(this,
                    geofencingEvent.getErrorCode());
            Log.e(TAG, errorMessage);
            return;
        }

        // Get the transition type.
        int geofenceTransition = geofencingEvent.getGeofenceTransition();

        // Test that the reported transition was of interest.
        if (geofenceTransition == Geofence.GEOFENCE_TRANSITION_ENTER ||
                geofenceTransition == Geofence.GEOFENCE_TRANSITION_EXIT) {

            // Get the geofences that were triggered. A single event can trigger multiple geofences.
            List<Geofence> triggeringGeofences = geofencingEvent.getTriggeringGeofences();

            // Get the transition details as a String.
            String geofenceTransitionDetails = getGeofenceTransitionDetails(
                    this,
                    geofenceTransition,
                    triggeringGeofences
            );

            // Send notification and log the transition details.
            sendNotification(geofenceTransitionDetails);
            Log.i(TAG, geofenceTransitionDetails);
        } else {
            // Log the error.
            Log.e(TAG, getString(R.string.geofence_transition_invalid_type, geofenceTransition));
        }
    }

    /**
     * Gets transition details and returns them as a formatted string.
     *
     * @param context               The app context.
     * @param geofenceTransition    The ID of the geofence transition.
     * @param triggeringGeofences   The geofence(s) triggered.
     * @return                      The transition details formatted as String.
     */
    private String getGeofenceTransitionDetails(
            Context context,
            int geofenceTransition,
            List<Geofence> triggeringGeofences) {

        String geofenceTransitionString = getTransitionString(geofenceTransition);

        // Get the Ids of each geofence that was triggered.
        ArrayList triggeringGeofencesIdsList = new ArrayList();
        for (Geofence geofence : triggeringGeofences) {
            triggeringGeofencesIdsList.add(geofence.getRequestId());
        }
        String triggeringGeofencesIdsString = TextUtils.join(", ",  triggeringGeofencesIdsList);

        return geofenceTransitionString + ": " + triggeringGeofencesIdsString;
    }

    /**
     * Posts a notification in the notification bar when a transition is detected.
     * If the user clicks the notification, control goes to the MainActivity.
     */
    private void sendNotification(String notificationDetails) {
        // Create an explicit content Intent that starts the main Activity.
        Intent notificationIntent = new Intent(getApplicationContext(), MainActivity.class);

        // Construct a task stack.
        TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);

        // Add the main Activity to the task stack as the parent.
        stackBuilder.addParentStack(MainActivity.class);

        // Push the content Intent onto the stack.
        stackBuilder.addNextIntent(notificationIntent);

        // Get a PendingIntent containing the entire back stack.
        PendingIntent notificationPendingIntent =
                stackBuilder.getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT);

        // Get a notification builder that's compatible with platform versions >= 4
        NotificationCompat.Builder builder = new NotificationCompat.Builder(this);

        // Define the notification settings.
        builder.setSmallIcon(R.drawable.ic_launcher)
                // In a real app, you may want to use a library like Volley
                // to decode the Bitmap.
                .setLargeIcon(BitmapFactory.decodeResource(getResources(),
                        R.drawable.ic_launcher))
                .setColor(Color.RED)
                .setContentTitle(notificationDetails)
                .setContentText(getString(R.string.geofence_transition_notification_text))
                .setContentIntent(notificationPendingIntent);

        // Dismiss notification once the user touches it.
        builder.setAutoCancel(true);

        // Get an instance of the Notification manager
        NotificationManager mNotificationManager =
                (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

        // Issue the notification
        mNotificationManager.notify(0, builder.build());
    }

    /**
     * Maps geofence transition types to their human-readable equivalents.
     *
     * @param transitionType    A transition type constant defined in Geofence
     * @return                  A String indicating the type of transition
     */
    private String getTransitionString(int transitionType) {
        switch (transitionType) {
            case Geofence.GEOFENCE_TRANSITION_ENTER:
                return getString(R.string.geofence_transition_entered);
            case Geofence.GEOFENCE_TRANSITION_EXIT:
                return getString(R.string.geofence_transition_exited);
            default:
                return getString(R.string.unknown_geofence_transition);
        }
    }
}

5.继承GoogleMap到android项目中；

详细参考可以看，参考

下面说说最关键的地方，其他地方的操作例如如何操地图，添加覆盖物等等则需要看说明文档了。

集成GoogleMap关键就是要申请用于Google地图的apikey，分正式的和测试的key;

正式的key是你打包上架时要用的；测试key是你平时用于测试调试的时候用的。

这2个key的生成是使用正式的keystoreh或者测试的keystore文件，然后利用keytool 工具生成对应的SHA1值，然后到google官网填写包名和SHA1去申请对应的apikey；

测试SHA1的值，keytool -list -v -keystore "%USERPROFILE%.androiddebug.keystore" -alias androiddebugkey -storepass android -keypass android

正式SHA1的值，keytool -list -v -keystore your_keystore_name -alias your_alias_name

your_alias_name为你生成正式keystore文件时填写的别名。