我是Android开发新手。我在Geofencing on tutsplus上遵循了关于地理围栏的基本教程。我成功创建了一个带有地理围栏的应用程序。我现在正试图在滑动选项卡式活动中实现地理围栏，我不知道它是否可能。我有三个java类，它是选项卡式活动的默认主要活动，片段和地理栅栏处理程序类。
下面是片段类
import android.Manifest;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.pm.PackageManager;
import android.graphics.Color;
import android.location.Location;
import android.net.Uri;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.content.ContextCompat;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.ResultCallback;
import com.google.android.gms.common.api.Status;
import com.google.android.gms.location.Geofence;
import com.google.android.gms.location.GeofencingRequest;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.maps.CameraUpdate;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapFragment;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.Circle;
import com.google.android.gms.maps.model.CircleOptions;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
/**
* A simple {@link Fragment} subclass.
* Activities that contain this fragment must implement the
* {@link Third.OnFragmentInteractionListener} interface
* to handle interaction events.
* Use the {@link Third#newInstance} factory method to
* create an instance of this fragment.
*/
public class Third extends SupportMapFragment implements
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener,
OnMapReadyCallback,
GoogleMap.OnMapClickListener,
GoogleMap.OnMarkerClickListener,
ResultCallback<Status>{
// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";
// TODO: Rename and change types of parameters
private String mParam1;
private String mParam2;
private OnFragmentInteractionListener mListener;
private static final String TAG = MainActivity.class.getSimpleName();
private GoogleMap map;
private GoogleApiClient googleApiClient;
private Location lastLocation;
private MapFragment mapFragment = (MapFragment) getFragmentManager().findFragmentById(R.id.map);
private static final String NOTIFICATION_MSG = "NOTIFICATION MSG";
// Create a Intent send by the notification
public static Intent makeNotificationIntent(Context context, String msg) {
Intent intent = new Intent( context, MainActivity.class );
intent.putExtra( NOTIFICATION_MSG, msg );
return intent;
}
public Third() {
// Required empty public constructor
}
/**
* Use this factory method to create a new instance of
* this fragment using the provided parameters.
*
* @param param1 Parameter 1.
* @param param2 Parameter 2.
* @return A new instance of fragment First.
*/
// TODO: Rename and change types and number of parameters
public static Third newInstance(String param1, String param2) {
Third fragment = new Third();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
setHasOptionsMenu(true);
// initialize GoogleMaps
initGMaps();
// create GoogleApiClient
createGoogleApi();
}
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.menu_a, menu);
super.onCreateOptionsMenu(menu, inflater);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch ( item.getItemId() ) {
case R.id.geofence: {
startGeofence();
return true;
}
case R.id.clear: {
clearGeofence();
return true;
}
}
return super.onOptionsItemSelected(item);
}
// Create GoogleApiClient instance
private void createGoogleApi() {
Log.d(TAG, "createGoogleApi()");
if ( googleApiClient == null ) {
googleApiClient = new GoogleApiClient.Builder( this )
.addConnectionCallbacks( this )
.addOnConnectionFailedListener( this )
.addApi( LocationServices.API )
.build();
}
}
@Override
public void onStart() {
super.onStart();
// Call GoogleApiClient connection when starting the Activity
googleApiClient.connect();
}
@Override
public void onStop() {
super.onStop();
// Disconnect GoogleApiClient when stopping Activity
googleApiClient.disconnect();
}
private final int REQ_PERMISSION = 999;
// Check for permission to access Location
private boolean checkPermission() {
Log.d(TAG, "checkPermission()");
// Ask for permission if it wasn't granted yet
return (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED );
}
// Asks for permission
private void askPermission() {
Log.d(TAG, "askPermission()");
}
// Verify user's response of the permission requested
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
Log.d(TAG, "onRequestPermissionsResult()");
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
switch ( requestCode ) {
case REQ_PERMISSION: {
if ( grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED ){
// Permission granted
getLastKnownLocation();
} else {
// Permission denied
permissionsDenied();
}
break;
}
}
}
// App cannot work without the permissions
private void permissionsDenied() {
Log.w(TAG, "permissionsDenied()");
// TODO close app and warn user
}
// Initialize GoogleMaps
private void initGMaps(){
mapFragment.getMapAsync(this);
}
// Callback called when Map is ready
@Override
public void onMapReady(GoogleMap googleMap) {
Log.d(TAG, "onMapReady()");
map = googleMap;
map.setOnMapClickListener(this);
map.setOnMarkerClickListener(this);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_first, container, false);
}
// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
if (mListener != null) {
mListener.onFragmentInteraction(uri);
}
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
@Override
public void onDetach() {
super.onDetach();
mListener = null;
}
@Override
public void onDestroy() {
super.onDestroy();
Fragment f = (Fragment) getFragmentManager().findFragmentById(R.id.map);
if (f != null) {
getFragmentManager().beginTransaction().remove(f).commit();
}
}
@Override
public void onConnected(@Nullable Bundle bundle) {
}
@Override
public void onConnectionSuspended(int i) {
Log.w(TAG, "onConnectionSuspended()");
}
@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
Log.w(TAG, "onConnectionFailed()");
}
@Override
public void onMapClick(LatLng latLng) {
Log.d(TAG, "onMapClick("+latLng +")");
markerForGeofence(latLng);
}
@Override
public boolean onMarkerClick(Marker marker) {
Log.d(TAG, "onMarkerClickListener: " + marker.getPosition() );
return false;
}
private LocationRequest locationRequest;
// Defined in mili seconds.
// This number in extremely low, and should be used only for debug
private final int UPDATE_INTERVAL = 1000;
private final int FASTEST_INTERVAL = 900;
// Start location Updates
private void startLocationUpdates(){
Log.i(TAG, "startLocationUpdates()");
locationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
.setInterval(UPDATE_INTERVAL)
.setFastestInterval(FASTEST_INTERVAL);
if ( checkPermission() )
LocationServices.FusedLocationApi.requestLocationUpdates(googleApiClient, locationRequest, this);
}
@Override
public void onLocationChanged(Location location) {
Log.d(TAG, "onLocationChanged ["+location+"]");
lastLocation = location;
writeActualLocation(location);
}
// Get last known location
private void getLastKnownLocation() {
Log.d(TAG, "getLastKnownLocation()");
if ( checkPermission() ) {
lastLocation = LocationServices.FusedLocationApi.getLastLocation(googleApiClient);
if ( lastLocation != null ) {
Log.i(TAG, "LasKnown location. " +
"Long: " + lastLocation.getLongitude() +
" | Lat: " + lastLocation.getLatitude());
writeLastLocation();
startLocationUpdates();
} else {
Log.w(TAG, "No location retrieved yet");
startLocationUpdates();
}
}
else askPermission();
}
private void writeActualLocation(Location location) {
markerLocation(new LatLng(location.getLatitude(), location.getLongitude()));
}
private void writeLastLocation() {
writeActualLocation(lastLocation);
}
private Marker locationMarker;
private void markerLocation(LatLng latLng) {
Log.i(TAG, "markerLocation("+latLng+")");
String title = latLng.latitude + ", " + latLng.longitude;
MarkerOptions markerOptions = new MarkerOptions()
.position(latLng)
.title(title);
if ( map!=null ) {
if ( locationMarker != null )
locationMarker.remove();
locationMarker = map.addMarker(markerOptions);
float zoom = 14f;
CameraUpdate cameraUpdate = CameraUpdateFactory.newLatLngZoom(latLng, zoom);
map.animateCamera(cameraUpdate);
}
}
private Marker geoFenceMarker;
private void markerForGeofence(LatLng latLng) {
Log.i(TAG, "markerForGeofence("+latLng+")");
String title = latLng.latitude + ", " + latLng.longitude;
// Define marker options
MarkerOptions markerOptions = new MarkerOptions()
.position(latLng)
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_ORANGE))
.title(title);
if ( map!=null ) {
// Remove last geoFenceMarker
if (geoFenceMarker != null)
geoFenceMarker.remove();
geoFenceMarker = map.addMarker(markerOptions);
}
}
// Start Geofence creation process
private void startGeofence() {
Log.i(TAG, "startGeofence()");
if( geoFenceMarker != null ) {
Geofence geofence = createGeofence( geoFenceMarker.getPosition(), GEOFENCE_RADIUS );
GeofencingRequest geofenceRequest = createGeofenceRequest( geofence );
addGeofence( geofenceRequest );
} else {
Log.e(TAG, "Geofence marker is null");
}
}
private static final long GEO_DURATION = 60 * 60 * 1000;
private static final String GEOFENCE_REQ_ID = "My Geofence";
private static final float GEOFENCE_RADIUS = 500.0f; // in meters
// Create a Geofence
private Geofence createGeofence( LatLng latLng, float radius ) {
Log.d(TAG, "createGeofence");
return new Geofence.Builder()
.setRequestId(GEOFENCE_REQ_ID)
.setCircularRegion( latLng.latitude, latLng.longitude, radius)
.setExpirationDuration( GEO_DURATION )
.setTransitionTypes( Geofence.GEOFENCE_TRANSITION_ENTER
| Geofence.GEOFENCE_TRANSITION_EXIT )
.build();
}
// Create a Geofence Request
private GeofencingRequest createGeofenceRequest( Geofence geofence ) {
Log.d(TAG, "createGeofenceRequest");
return new GeofencingRequest.Builder()
.setInitialTrigger( GeofencingRequest.INITIAL_TRIGGER_ENTER )
.addGeofence( geofence )
.build();
}
private PendingIntent geoFencePendingIntent;
private final int GEOFENCE_REQ_CODE = 0;
private PendingIntent createGeofencePendingIntent() {
Log.d(TAG, "createGeofencePendingIntent");
if ( geoFencePendingIntent != null )
return geoFencePendingIntent;
Intent intent = new Intent( this, GeofenceTrasitionService.class);
return PendingIntent.getService(this, GEOFENCE_REQ_CODE, intent, PendingIntent.FLAG_UPDATE_CURRENT );
}
// Add the created GeofenceRequest to the device's monitoring list
private void addGeofence(GeofencingRequest request) {
Log.d(TAG, "addGeofence");
if (checkPermission())
LocationServices.GeofencingApi.addGeofences(
googleApiClient,
request,
createGeofencePendingIntent()
).setResultCallback(this);
}
@Override
public void onResult(@NonNull Status status) {
Log.i(TAG, "onResult: " + status);
if ( status.isSuccess() ) {
saveGeofence();
drawGeofence();
} else {
// inform about fail
}
}
// Draw Geofence circle on GoogleMap
private Circle geoFenceLimits;
private void drawGeofence() {
Log.d(TAG, "drawGeofence()");
if ( geoFenceLimits != null )
geoFenceLimits.remove();
CircleOptions circleOptions = new CircleOptions()
.center( geoFenceMarker.getPosition())
.strokeColor(Color.argb(50, 70,70,70))
.fillColor( Color.argb(100, 150,150,150) )
.radius( GEOFENCE_RADIUS );
geoFenceLimits = map.addCircle( circleOptions );
}
private final String KEY_GEOFENCE_LAT = "GEOFENCE LATITUDE";
private final String KEY_GEOFENCE_LON = "GEOFENCE LONGITUDE";
// Saving GeoFence marker with prefs mng
private void saveGeofence() {
Log.d(TAG, "saveGeofence()");
SharedPreferences sharedPref = getPreferences( Context.MODE_PRIVATE );
SharedPreferences.Editor editor = sharedPref.edit();
editor.putLong( KEY_GEOFENCE_LAT, Double.doubleToRawLongBits( geoFenceMarker.getPosition().latitude ));
editor.putLong( KEY_GEOFENCE_LON, Double.doubleToRawLongBits( geoFenceMarker.getPosition().longitude ));
editor.apply();
}
// Recovering last Geofence marker
private void recoverGeofenceMarker() {
Log.d(TAG, "recoverGeofenceMarker");
SharedPreferences sharedPref = getPreferences( Context.MODE_PRIVATE );
if ( sharedPref.contains( KEY_GEOFENCE_LAT ) && sharedPref.contains( KEY_GEOFENCE_LON )) {
double lat = Double.longBitsToDouble( sharedPref.getLong( KEY_GEOFENCE_LAT, -1 ));
double lon = Double.longBitsToDouble( sharedPref.getLong( KEY_GEOFENCE_LON, -1 ));
LatLng latLng = new LatLng( lat, lon );
markerForGeofence(latLng);
drawGeofence();
}
}
// Clear Geofence
private void clearGeofence() {
Log.d(TAG, "clearGeofence()");
LocationServices.GeofencingApi.removeGeofences(
googleApiClient,
createGeofencePendingIntent()
).setResultCallback(new ResultCallback<Status>() {
@Override
public void onResult(@NonNull Status status) {
if ( status.isSuccess() ) {
// remove drawing
removeGeofenceDraw();
}
}
});
}
private void removeGeofenceDraw() {
Log.d(TAG, "removeGeofenceDraw()");
if ( geoFenceMarker != null)
geoFenceMarker.remove();
if ( geoFenceLimits != null )
geoFenceLimits.remove();
}
/**
* This interface must be implemented by activities that contain this
* fragment to allow an interaction in this fragment to be communicated
* to the activity and potentially other fragments contained in that
* activity.
* <p>
* See the Android Training lesson <a href=
* "http://developer.android.com/training/basics/fragments/communicating.html"
* >Communicating with Other Fragments</a> for more information.
*/
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
void onFragmentInteraction(Uri uri);
}
}
我的片段中出现以下错误： 无法解决方法＆＃39; getPreferences＆＃39;
private MapFragment mapFragment = (MapFragment) getFragment().findFragmentById(R.id.map)
不可转换的类型;无法投出＆＃39; android.support.v4.app.Fragment＆＃39;到＃com.google.android.gms.maps.MapFragment＆＃39;
助手类
public class GeofenceTrasitionService extends IntentService {
private static final String TAG = GeofenceTrasitionService.class.getSimpleName();
public static final int GEOFENCE_NOTIFICATION_ID = 0;
public GeofenceTrasitionService() {
super(TAG);
}
@Override
protected void onHandleIntent(Intent intent) {
GeofencingEvent geofencingEvent = GeofencingEvent.fromIntent(intent);
// Handling errors
if ( geofencingEvent.hasError() ) {
String errorMsg = getErrorString(geofencingEvent.getErrorCode() );
Log.e( TAG, errorMsg );
return;
}
int geoFenceTransition = geofencingEvent.getGeofenceTransition();
// Check if the transition type is of interest
if ( geoFenceTransition == Geofence.GEOFENCE_TRANSITION_ENTER ||
geoFenceTransition == Geofence.GEOFENCE_TRANSITION_EXIT ) {
// Get the geofence that were triggered
List<Geofence> triggeringGeofences = geofencingEvent.getTriggeringGeofences();
String geofenceTransitionDetails = getGeofenceTrasitionDetails(geoFenceTransition, triggeringGeofences );
// Send notification details as a String
sendNotification( geofenceTransitionDetails );
}
}
private String getGeofenceTrasitionDetails(int geoFenceTransition, List<Geofence> triggeringGeofences) {
// get the ID of each geofence triggered
ArrayList<String> triggeringGeofencesList = new ArrayList<>();
for ( Geofence geofence : triggeringGeofences ) {
triggeringGeofencesList.add( geofence.getRequestId() );
}
String status = null;
if ( geoFenceTransition == Geofence.GEOFENCE_TRANSITION_ENTER )
status = "Entering ";
else if ( geoFenceTransition == Geofence.GEOFENCE_TRANSITION_EXIT )
status = "Exiting ";
return status + TextUtils.join( ", ", triggeringGeofencesList);
}
@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN)
private void sendNotification(String msg ) {
Log.i(TAG, "sendNotification: " + msg );
// Intent to start the main Activity
Intent notificationIntent = Third.makeNotificationIntent(
getApplicationContext(), msg
);
TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);
stackBuilder.addParentStack(Third.class);
stackBuilder.addNextIntent(notificationIntent);
PendingIntent notificationPendingIntent = stackBuilder.getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT);
// Creating and sending Notification
NotificationManager notificatioMng =
(NotificationManager) getSystemService( Context.NOTIFICATION_SERVICE );
notificatioMng.notify(
GEOFENCE_NOTIFICATION_ID,
createNotification(msg, notificationPendingIntent));
}
// Create notification
private Notification createNotification(String msg, PendingIntent notificationPendingIntent) {
NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this);
notificationBuilder
.setSmallIcon(R.drawable.ic_action_location)
.setColor(Color.RED)
.setContentTitle(msg)
.setContentText("Geofence Notification!")
.setContentIntent(notificationPendingIntent)
.setDefaults(Notification.DEFAULT_LIGHTS | Notification.DEFAULT_VIBRATE | Notification.DEFAULT_SOUND)
.setAutoCancel(true);
return notificationBuilder.build();
}
private static String getErrorString(int errorCode) {
switch (errorCode) {
case GeofenceStatusCodes.GEOFENCE_NOT_AVAILABLE:
return "GeoFence not available";
case GeofenceStatusCodes.GEOFENCE_TOO_MANY_GEOFENCES:
return "Too many GeoFences";
case GeofenceStatusCodes.GEOFENCE_TOO_MANY_PENDING_INTENTS:
return "Too many pending intents";
default:
return "Unknown error.";
}
}
}
选项卡式活动返回3个选项卡，其他两个选项卡为空。我还可以在选项卡式活动中使用多个地图。任何有关最佳Android开发实践的帮助和指导都将受到高度赞赏