我正在实施一个显示最近餐馆的应用程序。我想要有两个活动，一个用于在地图中显示餐馆，另一个用于在ListView中显示。
这是检索数据添加标记的代码。
public class GetNearbyPlacesData extends AsyncTask<Object, String, String> {
String googlePlacesData;
GoogleMap mMap;
String url;
@Override
protected String doInBackground(Object... params) {
try {
Log.d("GetNearbyPlacesData", "doInBackground entered");
mMap = (GoogleMap) params[0];
url = (String) params[1];
DownloadUrl downloadUrl = new DownloadUrl();
googlePlacesData = downloadUrl.readUrl(url);
Log.d("GooglePlaceData", googlePlacesData);
Log.d("GooglePlacesReadTask", "doInBackground Exit");
} catch (Exception e) {
Log.d("GooglePlacesReadTask", e.toString());
}
return googlePlacesData;
}
@Override
protected void onPostExecute(String result) {
Log.d("GooglePlacesReadTask", "onPostExecute Entered");
List<HashMap<String, String>> nearbyPlacesList = null;
DataParser dataParser = new DataParser();
nearbyPlacesList = dataParser.parse(result);
Log.d("List of restaurants",nearbyPlacesList.toString());
ShowNearbyPlaces(nearbyPlacesList);
Log.d("GooglePlacesReadTask", "onPostExecute Exit");
}
private void ShowNearbyPlaces(List<HashMap<String, String>> nearbyPlacesList) {
for (int i = 0; i < nearbyPlacesList.size(); i++) {
Log.d("onPostExecute","Entered into showing locations");
MarkerOptions markerOptions = new MarkerOptions();
HashMap<String, String> googlePlace = nearbyPlacesList.get(i);
double lat = Double.parseDouble(googlePlace.get("lat"));
double lng = Double.parseDouble(googlePlace.get("lng"));
String placeName = googlePlace.get("place_name");
String vicinity = googlePlace.get("vicinity");
LatLng latLng = new LatLng(lat, lng);
markerOptions.position(latLng);
markerOptions.title(placeName + " : " + vicinity);
mMap.addMarker(markerOptions);
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_RED));
//move map camera
mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
mMap.animateCamera(CameraUpdateFactory.zoomTo(11));
}
}
}
解析数据的代码：
public class DataParser {
public List<HashMap<String, String>> parse(String jsonData) {
JSONArray jsonArray = null;
JSONObject jsonObject;
try {
Log.d("Places", "parse");
jsonObject = new JSONObject(jsonData);
jsonArray = jsonObject.getJSONArray("results");
} catch (JSONException e) {
Log.d("Places", "parse error");
e.printStackTrace();
}
return getPlaces(jsonArray);
}
private List<HashMap<String, String>> getPlaces(JSONArray jsonArray) {
int placesCount = jsonArray.length();
List<HashMap<String, String>> placesList = new ArrayList<>();
HashMap<String, String> placeMap = null;
Log.d("Places", "getPlaces");
for (int i = 0; i < placesCount; i++) {
try {
placeMap = getPlace((JSONObject) jsonArray.get(i));
placesList.add(placeMap);
Log.d("Places", "Adding places");
} catch (JSONException e) {
Log.d("Places", "Error in Adding places");
e.printStackTrace();
}
}
return placesList;
}
private HashMap<String, String> getPlace(JSONObject googlePlaceJson) {
HashMap<String, String> googlePlaceMap = new HashMap<String, String>();
String placeName = "-NA-";
String vicinity = "-NA-";
String latitude = "";
String longitude = "";
String reference = "";
Log.d("getPlace", "Entered");
try {
if (!googlePlaceJson.isNull("name")) {
placeName = googlePlaceJson.getString("name");
}
if (!googlePlaceJson.isNull("vicinity")) {
vicinity = googlePlaceJson.getString("vicinity");
}
latitude = googlePlaceJson.getJSONObject("geometry").getJSONObject("location").getString("lat");
longitude = googlePlaceJson.getJSONObject("geometry").getJSONObject("location").getString("lng");
reference = googlePlaceJson.getString("reference");
googlePlaceMap.put("place_name", placeName);
googlePlaceMap.put("vicinity", vicinity);
googlePlaceMap.put("lat", latitude);
googlePlaceMap.put("lng", longitude);
googlePlaceMap.put("reference", reference);
Log.d("getPlace", "Putting Places");
} catch (JSONException e) {
Log.d("getPlace", "Error");
e.printStackTrace();
}
return googlePlaceMap;
}
}
这适用于HTTPConnection：
public class DownloadUrl {
public String readUrl(String strUrl) throws IOException {
String data = "";
InputStream iStream = null;
HttpURLConnection urlConnection = null;
try {
URL url = new URL(strUrl);
// Creating an http connection to communicate with url
urlConnection = (HttpURLConnection) url.openConnection();
// Connecting to url
urlConnection.connect();
// Reading data from url
iStream = urlConnection.getInputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(iStream));
StringBuffer sb = new StringBuffer();
String line = "";
while ((line = br.readLine()) != null) {
sb.append(line);
}
data = sb.toString();
Log.d("downloadUrl", data.toString());
br.close();
} catch (Exception e) {
Log.d("Exception", e.toString());
} finally {
iStream.close();
urlConnection.disconnect();
}
return data;
}
}
这是我试图检索回复的内容：
public class ListRestActivity extends AppCompatActivity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
new GetNearbyPlacesData().execute();
}
}
修改
添加了检索我的纬度和经度并构建我的网址的活动：
public class MapsActivity extends FragmentActivity implements OnMapReadyCallback,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener {
private GoogleMap mMap;
double latitude;
double longitude;
private int PROXIMITY_RADIUS = 10000;
GoogleApiClient mGoogleApiClient;
Location mLastLocation;
Marker mCurrLocationMarker;
LocationRequest mLocationRequest;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
checkLocationPermission();
}
//Check if Google Play Services Available or not
if (!CheckGooglePlayServices()) {
Log.d("onCreate", "Finishing test case since Google Play Services are not available");
finish();
}
else {
Log.d("onCreate","Google Play Services available.");
}
// Obtain the SupportMapFragment and get notified when the map is ready to be used.
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
}
private boolean CheckGooglePlayServices() {
GoogleApiAvailability googleAPI = GoogleApiAvailability.getInstance();
int result = googleAPI.isGooglePlayServicesAvailable(this);
if(result != ConnectionResult.SUCCESS) {
if(googleAPI.isUserResolvableError(result)) {
googleAPI.getErrorDialog(this, result,
0).show();
}
return false;
}
return true;
}
/**
* Manipulates the map once available.
* This callback is triggered when the map is ready to be used.
* This is where we can add markers or lines, add listeners or move the camera. In this case,
* we just add a marker near Sydney, Australia.
* If Google Play services is not installed on the device, the user will be prompted to install
* it inside the SupportMapFragment. This method will only be triggered once the user has
* installed Google Play services and returned to the app.
*/
@Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
mMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
//Initialize Google Play Services
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
buildGoogleApiClient();
mMap.setMyLocationEnabled(true);
}
}
else {
buildGoogleApiClient();
mMap.setMyLocationEnabled(true);
}
String Restaurant = "restaurant";
mMap.clear();
String url = getUrl(latitude, longitude, Restaurant);
Object[] DataTransfer = new Object[2];
DataTransfer[0] = mMap;
DataTransfer[1] = url;
GetNearbyPlacesData getNearbyPlacesData = new GetNearbyPlacesData();
getNearbyPlacesData.execute(DataTransfer);
Toast.makeText(MapsActivity.this,"Nearby Restaurants", Toast.LENGTH_LONG).show();
}
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mGoogleApiClient.connect();
}
@Override
public void onConnected(Bundle bundle) {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(1000);
mLocationRequest.setFastestInterval(1000);
mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
}
private String getUrl(double latitude, double longitude, String nearbyPlace) {
//Place current location marker
latitude = 45.772;
longitude = 21.219;
StringBuilder googlePlacesUrl = new StringBuilder("https://maps.googleapis.com/maps/api/place/nearbysearch/json?");
googlePlacesUrl.append("location=" + latitude + "," + longitude);
googlePlacesUrl.append("&radius=" + PROXIMITY_RADIUS);
googlePlacesUrl.append("&type=" + nearbyPlace);
googlePlacesUrl.append("&sensor=true");
googlePlacesUrl.append("&key=" + "-");
Log.d("getUrl", googlePlacesUrl.toString());
return (googlePlacesUrl.toString());
}
@Override
public void onConnectionSuspended(int i) {
}
@Override
public void onLocationChanged(Location location) {
Log.d("onLocationChanged", "entered");
mLastLocation = location;
if (mCurrLocationMarker != null) {
mCurrLocationMarker.remove();
}
//Place current location marker
latitude = location.getLatitude();
longitude = location.getLongitude();
LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(latLng);
markerOptions.title("Current Position");
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
mCurrLocationMarker = mMap.addMarker(markerOptions);
//move map camera
mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
mMap.animateCamera(CameraUpdateFactory.zoomTo(11));
Toast.makeText(MapsActivity.this,"Your Current Location", Toast.LENGTH_LONG).show();
Log.d("onLocationChanged", String.format("latitude:%.3f longitude:%.3f",latitude,longitude));
//stop location updates
if (mGoogleApiClient != null) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
Log.d("onLocationChanged", "Removing Location Updates");
}
Log.d("onLocationChanged", "Exit");
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
}
public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
public boolean checkLocationPermission(){
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
// Asking user if explanation is needed
if (ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.ACCESS_FINE_LOCATION)) {
// Show an explanation to the user *asynchronously* -- don't block
// this thread waiting for the user's response! After the user
// sees the explanation, try again to request the permission.
//Prompt the user once explanation has been shown
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION);
} else {
// No explanation needed, we can request the permission.
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION);
}
return false;
} else {
return true;
}
}
@Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case MY_PERMISSIONS_REQUEST_LOCATION: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// permission was granted. Do the
// contacts-related task you need to do.
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
if (mGoogleApiClient == null) {
buildGoogleApiClient();
}
mMap.setMyLocationEnabled(true);
}
} else {
// Permission denied, Disable the functionality that depends on this permission.
Toast.makeText(this, "permission denied", Toast.LENGTH_LONG).show();
}
return;
}
// other 'case' lines to check for other permissions this app might request.
// You can add here other case statements according to your requirement.
}
}
}
logcat的：
1-16 16:18:12.101 4224-4224/com.upt.cti.nearbyrestaurant E/AndroidRuntime: FATAL EXCEPTION: main
java.lang.NullPointerException
at org.json.JSONTokener.nextCleanInternal(JSONTokener.java:116)
at org.json.JSONTokener.nextValue(JSONTokener.java:94)
at org.json.JSONObject.<init>(JSONObject.java:154)
at org.json.JSONObject.<init>(JSONObject.java:171)
at com.upt.cti.nearbyrestaurant.DataParser.parse(DataParser.java:25)
at com.upt.cti.nearbyrestaurant.GetNearbyPlacesData.onPostExecute(GetNearbyPlacesData.java:46)
at com.upt.cti.nearbyrestaurant.GetNearbyPlacesData.onPostExecute(GetNearbyPlacesData.java:19)
at android.os.AsyncTask.finish(AsyncTask.java:631)
at android.os.AsyncTask.access$600(AsyncTask.java:177)
at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:644)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4963)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1038)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:805)
at dalvik.system.NativeStart.main(Native Method)
我收到NullpointerException。这还不够吗？有人能帮助我吗？
答案 0 :(得分：0)
我使用了Androidhive的精彩教程，link here.你检查了吗，结果是什么？onPostExecute？它变为null，解析或检索？
答案 1 :(得分：0)
Maps Activity.java
package com.android.trainee.activity;
import android.Manifest;
import android.content.Intent;
import android.content.IntentSender;
import android.content.pm.PackageManager;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.os.Build;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.FragmentActivity;
import android.support.v4.content.ContextCompat;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.widget.Toast;
import com.android.trainee.R;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.PendingResult;
import com.google.android.gms.common.api.Result;
import com.google.android.gms.common.api.ResultCallback;
import com.google.android.gms.common.api.Status;
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.location.LocationSettingsRequest;
import com.google.android.gms.location.LocationSettingsStatusCodes;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
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.CameraPosition;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import java.util.ArrayList;
import java.util.List;
public class MapsActivity extends FragmentActivity implements
OnMapReadyCallback,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener {
GoogleMap mGoogleMap;
LocationRequest mLocationRequest;
private GoogleApiClient googleApiClient;
Location mLastLocation;
Marker mCurrLocationMarker;
private final int[] MAP_TYPES = {GoogleMap.MAP_TYPE_SATELLITE,
GoogleMap.MAP_TYPE_NORMAL,
GoogleMap.MAP_TYPE_HYBRID,
GoogleMap.MAP_TYPE_TERRAIN,
GoogleMap.MAP_TYPE_NONE};
private int curMapTypeIndex = 1;
int REQUEST_CHECK_SETTINGS = 100;
Marker currLocationMarker;
MarkerOptions markerOptions;
String result;
View mapView;
ListView simpleList;
ArrayList<String> aa = new ArrayList<String>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
// Obtain the SupportMapFragment and get notified when the map is ready
to be used.
SupportMapFragment mapFragment = (SupportMapFragment)
getSupportFragmentManager()
.findFragmentById(R.id.map);
mapView = mapFragment.getView();
mapFragment.getMapAsync(this);
simpleList = (ListView) findViewById(R.id.simpleListView);
}
private void gps() {
if (googleApiClient == null) {
googleApiClient = new
GoogleApiClient.Builder(getApplicationContext())
.addApi(LocationServices.API).build();
googleApiClient.connect();
location();
}
}
private void location() {
LocationRequest locationRequest = LocationRequest.create();
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
locationRequest.setInterval(1000);
locationRequest.setFastestInterval(100);
LocationSettingsRequest.Builder builder = new
LocationSettingsRequest.Builder()
.addLocationRequest(locationRequest);
builder.setAlwaysShow(false); // this is the key ingredient
PendingResult result = LocationServices.SettingsApi.
checkLocationSettings(googleApiClient, builder.build());
result.setResultCallback(new ResultCallback() {
@Override
public void onResult(@NonNull Result result) {
final Status status = result.getStatus();
switch (status.getStatusCode()) {
case LocationSettingsStatusCodes.SUCCESS:
break;
case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
try {
status.startResolutionForResult(MapsActivity.this,
REQUEST_CHECK_SETTINGS);
} catch (IntentSender.SendIntentException e) {
}
break;
case
LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
break;
}
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent
data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == REQUEST_CHECK_SETTINGS) {
if (resultCode == RESULT_OK) {
Toast.makeText(getApplicationContext(), "GPS enabled",
Toast.LENGTH_LONG).show();
} else {
location();
}
}
}
/**
* Manipulates the map once available.
* This callback is triggered when the map is ready to be used.
* This is where we can add markers or lines, add listeners or move the
camera. In this case,
* we just add a marker near Sydney, Australia.
* If Google Play services is not installed on the device, the user will be
prompted to install
* it inside the SupportMapFragment. This method will only be triggered once
the user has
* installed Google Play services and returned to the app.
*/
@Override
public void onMapReady(GoogleMap googleMap) {
gps();
mGoogleMap = googleMap;
mGoogleMap.setMapType(MAP_TYPES[curMapTypeIndex]);
//Initialize Google Play Services
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
//Location Permission already granted
mGoogleMap.setMyLocationEnabled(true);
// mGoogleMap.getUiSettings().setZoomControlsEnabled(true);
mGoogleMap.setOnMapClickListener(new
GoogleMap.OnMapClickListener() {
@Override
public void onMapClick(LatLng latLng) {
//save current location
getAddress(latLng);
location(latLng);
}
});
if (mapView != null &&
mapView.findViewById(Integer.parseInt("1")) != null) {
// Get the button view
View locationButton = ((View)
mapView.findViewById(Integer.parseInt("1"))
.getParent()).findViewById(Integer.parseInt("2"));
// and next place it, on bottom right (as Google Maps app)
RelativeLayout.LayoutParams layoutParams =
(RelativeLayout.LayoutParams)
locationButton.getLayoutParams();
// position on right bottom
layoutParams.addRule(RelativeLayout.ALIGN_PARENT_TOP, 0);
layoutParams.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM,
RelativeLayout.TRUE);
layoutParams.setMargins(0, 0, 30, 30);
}
mGoogleMap.setOnCameraChangeListener(new
GoogleMap.OnCameraChangeListener() {
@Override
public void onCameraChange(final CameraPosition
cameraPosition) {
mGoogleMap.setOnMapLoadedCallback(new
GoogleMap.OnMapLoadedCallback() {
@Override
public void onMapLoaded() {
LatLng latLng =
mGoogleMap.getCameraPosition().target;
getAddress(latLng);
}
});
}
});
} else {
//Request Location Permission
gps();
}
} else {
mGoogleMap.setMyLocationEnabled(true);
// mGoogleMap.getUiSettings().setZoomControlsEnabled(true);
mGoogleMap.setOnMapClickListener(new GoogleMap.OnMapClickListener()
{
@Override
public void onMapClick(LatLng latLng) {
//save current location
getAddress(latLng);
location(latLng);
}
});
if (mapView != null &&
mapView.findViewById(Integer.parseInt("1")) != null) {
// Get the button view
View locationButton = ((View)
mapView.findViewById(Integer.parseInt("1"))
.getParent()).findViewById(Integer.parseInt("2"));
// and next place it, on bottom right (as Google Maps app)
RelativeLayout.LayoutParams layoutParams =
(RelativeLayout.LayoutParams)
locationButton.getLayoutParams();
// position on right bottom
layoutParams.addRule(RelativeLayout.ALIGN_PARENT_TOP, 0);
layoutParams.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM,
RelativeLayout.TRUE);
layoutParams.setMargins(0, 0, 30, 30);
}
mGoogleMap.setOnCameraChangeListener(new
GoogleMap.OnCameraChangeListener() {
@Override
public void onCameraChange(final CameraPosition cameraPosition)
{
mGoogleMap.setOnMapLoadedCallback(new
GoogleMap.OnMapLoadedCallback() {
@Override
public void onMapLoaded() {
LatLng latLng =
mGoogleMap.getCameraPosition().target;
getAddress(latLng);
}
});
}
});
}
}
public void location(LatLng latLng) {
markerOptions = new MarkerOptions();
markerOptions.position(latLng);
markerOptions.title(result);
markerOptions.icon(BitmapDescriptorFactory.fromResource(R.drawable.marker));
currLocationMarker = mGoogleMap.addMarker(markerOptions);
}
public List<Address> getAddress(LatLng latLng) {
try {
Geocoder geocoder;
List<Address> addresses;
geocoder = new Geocoder(this);
if (latLng.latitude != 0 || latLng.longitude != 0) {
addresses = geocoder.getFromLocation(latLng.latitude,
latLng.longitude, 1);
String address = addresses.get(0).getAddressLine(0);
String city = addresses.get(0).getAddressLine(1);
String country = addresses.get(0).getAddressLine(2);
Toast.makeText(this, address + " - " + city + " - " + country,
Toast.LENGTH_LONG).show();
aa.add(address + city + country);
ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>
(this, R.layout.activity_listview, R.id.textView, aa);
simpleList.setAdapter(arrayAdapter);
return addresses;
} else {
Toast.makeText(this, "latitude and longitude are null",
Toast.LENGTH_LONG).show();
return null;
}
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
@Override
public void onConnected(@Nullable Bundle bundle) {
// gpsTreker();
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(1000);
mLocationRequest.setFastestInterval(1000);
mLocationRequest.setPriority
(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
LocationServices.FusedLocationApi.requestLocationUpdates(googleApiClient,
mLocationRequest, this);
}
}
@Override
public void onConnectionSuspended(int i) {
}
@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
}
@Override
public void onLocationChanged(Location location) {
mLastLocation = location;
if (mCurrLocationMarker != null) {
mCurrLocationMarker.remove();
}
//Place current location marker
LatLng latLng = new LatLng(location.getLatitude(),
location.getLongitude());
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(latLng);
markerOptions.title("Current Position");
markerOptions.icon(BitmapDescriptorFactory.defaultMarker
(BitmapDescriptorFactory.HUE_MAGENTA));
mCurrLocationMarker = mGoogleMap.addMarker(markerOptions);
//move map camera
mGoogleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng, 12));
}
}
activity_maps.xml
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:map="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/map"
android:name="com.google.android.gms.maps.SupportMapFragment"
android:layout_width="match_parent"
android:layout_height="360dp"
tools:context="com.android.trainee.activity.MapsActivity">
</fragment>
<ListView
android:id="@+id/simpleListView"
android:layout_width="fill_parent"
android:layout_height="200dp"
android:divider="#cfc4c4"
android:dividerHeight="1dp"/>
</LinearLayout>
</ScrollView>
activity_listview。 XML
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/textView"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:padding="@dimen/activity_horizontal_margin"
android:textColor="@color/colorPrimaryDarktab" />
</LinearLayout>
android manifast.xml
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.android.trainee">
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_CONTACTS" />
<uses-permission android:name="android.permission.WRITE_CONTACTS" />
<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" />
<!--
The ACCESS_COARSE/FINE_LOCATION permissions are not required to use
Google Maps Android API v2, but you must specify either coarse or fine
location permissions for the 'MyLocation' functionality.
-->
<uses-feature
android:glEsVersion="0x00020000"
android:required="true" />
<!-- <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"
/> -->
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/Theme.AppCompat.Light.NoActionBar">
<activity
android:name=".activity.HomeSplashActivity"
android:launchMode="singleInstance"
android:theme="@android:style/Theme.NoTitleBar.Fullscreen">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".activity.SignUpActivity" />
<activity android:name=".activity.LoginActivity" />
<activity
android:name=".activity.DashBoard"
android:label="@string/title_activity_dash_board"
android:theme="@style/Theme.AppCompat.Light.NoActionBar" />
<activity android:name=".activity.ProfileActivity" />
<activity android:name=".activity.Contects" />
<!--
The API key for Google Maps-based APIs is defined as a string
resource.
(See the file "res/values/google_maps_api.xml").
Note that the API key is linked to the encryption key used to sign
the APK.
You need a different API key for each encryption key, including the
release key that is used to
sign the APK for publishing.
You can define the keys for the debug and release targets in
src/debug/ and src/release/.
-->
<meta-data
android:name="com.google.android.geo.API_KEY"
android:value="@string/google_maps_key" />
<activity
android:name=".activity.MapsActivity"
android:configChanges="orientation|keyboardHidden|screenSize"
android:label="@string/title_activity_maps" />
<activity android:name=".activity.BackgroundServices"></activity>
<service android:name=".services.MediaService" />
</application>
</manifest>``