我正在尝试添加一种方法来查看我的应用程序的当前位置，并且无法弄清楚如何在不出错的情况下执行此操作。我目前将两个错误地存储在单独的活动中（一个活动中的标记位置和我在其他活动中的位置）并且似乎无法将它们组合在一起。 对于描述我的问题的可怜尝试感到抱歉，希望此代码可以提供更多帮助。
MainActivity
package com.kieranmaps.v2maps;
import java.util.Hashtable;
import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.app.ActivityManager;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.view.View;
import android.widget.ImageView;
import android.widget.TextView;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.GoogleMap.InfoWindowAdapter;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
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 com.kieranmaps.v2maps.R;
import com.nostra13.universalimageloader.cache.disc.naming.Md5FileNameGenerator;
import com.nostra13.universalimageloader.cache.memory.impl.FIFOLimitedMemoryCache;
import com.nostra13.universalimageloader.core.DisplayImageOptions;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;
import com.nostra13.universalimageloader.core.assist.QueueProcessingType;
import com.nostra13.universalimageloader.core.assist.SimpleImageLoadingListener;
public class MainActivity extends FragmentActivity {
private GoogleMap googleMap;
private final LatLng OREILLYS = new LatLng(53.348347, -6.254119);
private final LatLng LAGOONA = new LatLng(53.349810, -6.243160);
private final LatLng COPPERS = new LatLng (53.335356, -6.263481);
private final LatLng WRIGHTS = new LatLng (53.445491, -6.223857);
private final LatLng ACADEMY = new LatLng (53.348045,-6.26198);
private final LatLng DICEYS = new LatLng (53.347250, -6.254198);
private final LatLng PYGMALION = new LatLng (53.342183,-6.262358);
private final LatLng FIBBERS = new LatLng (53.352799,-6.260412);
// private final LatLng TEST = new LatLng (5352799,-6.260412);
private Marker marker;
private Hashtable<String, String> markers;
private ImageLoader imageLoader;
private DisplayImageOptions options;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
googleMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map))
.getMap();
initImageLoader();
markers = new Hashtable<String, String>();
imageLoader = ImageLoader.getInstance();
options = new DisplayImageOptions.Builder()
.showStubImage(R.drawable.ic_launcher) // Display Stub Image
.showImageForEmptyUri(R.drawable.ic_launcher) // If Empty image found
.cacheInMemory()
.cacheOnDisc().bitmapConfig(Bitmap.Config.RGB_565).build();
if ( googleMap != null ) {
googleMap.setInfoWindowAdapter(new CustomInfoWindowAdapter());
final Marker oreillys = googleMap.addMarker(new MarkerOptions().position(OREILLYS)
.title("O Reillys"));
markers.put(oreillys.getId(), "http://img.india-forums.com/images/100x100/37525-a-still-image-of-akshay-kumar.jpg");
googleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(OREILLYS, 15));
googleMap.animateCamera(CameraUpdateFactory.zoomTo(10), 2000, null);
final Marker coppers = googleMap.addMarker(new MarkerOptions().position(COPPERS)
.title("Coppers"));
markers.put(coppers.getId(), "http://f3.thejournal.ie/media/2011/11/coppers1-390x285.png");
final Marker wrights = googleMap.addMarker(new MarkerOptions().position(WRIGHTS)
.title("The Wright Venue"));
markers.put(wrights.getId(), "http://www.turbosound.com/public/images/news_img_thumbs/Wright_Venue_Dancefloor-thumb.jpg");
final Marker lagoona = googleMap.addMarker(new MarkerOptions().position(LAGOONA)
.title("The Lagoona"));
markers.put(lagoona.getId(), "http://www.turbosound.com/public/images/news_img_thumbs/Wright_Venue_Dancefloor-thumb.jpg");
final Marker academy = googleMap.addMarker(new MarkerOptions().position(ACADEMY)
.title("The Academy"));
markers.put(academy.getId(), "http://www.turbosound.com/public/images/news_img_thumbs/Wright_Venue_Dancefloor-thumb.jpg");
final Marker pygmalion = googleMap.addMarker(new MarkerOptions().position(PYGMALION)
.title("The Pygmalion"));
markers.put(pygmalion.getId(), "http://www.turbosound.com/public/images/news_img_thumbs/Wright_Venue_Dancefloor-thumb.jpg");
final Marker fibbers = googleMap.addMarker(new MarkerOptions().position(FIBBERS)
.title("Fibbers"));
markers.put(fibbers.getId(), "http://www.turbosound.com/public/images/news_img_thumbs/Wright_Venue_Dancefloor-thumb.jpg");
final Marker diceys = googleMap.addMarker(new MarkerOptions().position(DICEYS)
.title("Dicey's"));
markers.put(diceys.getId(), "https://dublinnow.files.wordpress.com/2012/05/diceys.jpg");
/* final Marker diceys = googleMap.addMarker(new MarkerOptions()
.position(DICEYS)
.title("Diceys")
.snippet("Drink Deal: 3.50. Adm: 5, Performance: Gen"));
Marker marker = GoogleMap.addMarker(new MarkerOptions()
.position(latLng)
.title("Title")
.snippet("Snippet")
.icon(BitmapDescriptorFactory
.fromResource(R.drawable.marker))); */
//marker.showInfoWindow();
}
}
private class CustomInfoWindowAdapter implements InfoWindowAdapter {
private View view;
public CustomInfoWindowAdapter() {
view = getLayoutInflater().inflate(R.layout.custom_info_window,
null);
}
@Override
public View getInfoContents(Marker marker) {
if (MainActivity.this.marker != null
&& MainActivity.this.marker.isInfoWindowShown()) {
MainActivity.this.marker.hideInfoWindow();
MainActivity.this.marker.showInfoWindow();
}
return null;
}
@Override
public View getInfoWindow(final Marker marker) {
MainActivity.this.marker = marker;
String url = null;
if (marker.getId() != null && markers != null && markers.size() > 0) {
if ( markers.get(marker.getId()) != null &&
markers.get(marker.getId()) != null) {
url = markers.get(marker.getId());
}
}
final ImageView image = ((ImageView) view.findViewById(R.id.badge));
if (url != null && !url.equalsIgnoreCase("null")
&& !url.equalsIgnoreCase("")) {
imageLoader.displayImage(url, image, options,
new SimpleImageLoadingListener() {
@Override
public void onLoadingComplete(String imageUri,
View view, Bitmap loadedImage) {
super.onLoadingComplete(imageUri, view,
loadedImage);
getInfoContents(marker);
}
});
} else {
image.setImageResource(R.drawable.ic_launcher);
}
//
final String title = marker.getTitle();
final TextView titleUi = ((TextView) view.findViewById(R.id.title));
if (title != null) {
titleUi.setText(title);
} else {
titleUi.setText("");
}
final String snippet = marker.getSnippet();
final TextView snippetUi = ((TextView) view
.findViewById(R.id.snippet));
if (snippet != null) {
snippetUi.setText(snippet);
} else {
snippetUi.setText("");
}
return view;
}
}
private void initImageLoader() {
int memoryCacheSize;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ECLAIR) {
int memClass = ((ActivityManager)
getSystemService(Context.ACTIVITY_SERVICE))
.getMemoryClass();
memoryCacheSize = (memClass / 8) * 1024 * 1024;
} else {
memoryCacheSize = 2 * 1024 * 1024;
}
final ImageLoaderConfiguration config = new ImageLoaderConfiguration.Builder(
this).threadPoolSize(5)
.threadPriority(Thread.NORM_PRIORITY - 2)
.memoryCacheSize(memoryCacheSize)
.memoryCache(new FIFOLimitedMemoryCache(memoryCacheSize-1000000))
.denyCacheImageMultipleSizesInMemory()
.discCacheFileNameGenerator(new Md5FileNameGenerator())
.tasksProcessingOrder(QueueProcessingType.LIFO).enableLogging()
.build();
ImageLoader.getInstance().init(config);
}
}
NewActivity：
package com.kieranmaps.v2maps;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.json.JSONObject;
import android.content.Context;
import android.graphics.Color;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.util.Log;
import android.view.Menu;
import android.widget.Toast;
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.SupportMapFragment;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.gms.maps.model.PolylineOptions;
public class NewActivity extends FragmentActivity {
GoogleMap map;
ArrayList<LatLng> markerPoints;
private double sourceLatitude, sourceLongitude;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Initializing
markerPoints = new ArrayList<LatLng>();
// Getting reference to SupportMapFragment of the activity_main
SupportMapFragment fm = (SupportMapFragment)getSupportFragmentManager().findFragmentById(R.id.map);
// Getting Map for the SupportMapFragment
map = fm.getMap();
// Enable MyLocation Button in the Map
map.setMyLocationEnabled(true);
LocationManager mlocManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
LocationListener mlocListener = new MyLocationListener();
mlocManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 10, 0,
mlocListener);
mlocManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER,
10, 0, mlocListener);
// // Setting onclick event listener for the map
// map.setOnMapClickListener(new OnMapClickListener() {
//
// @Override
// public void onMapClick(LatLng point) {
//
// Toast.makeText(getApplicationContext(), "Clicked !", Toast.LENGTH_SHORT).show();
//
// // Already two locations
// if(markerPoints.size()>1){
// markerPoints.clear();
// map.clear();
// }
//
// // Adding new item to the ArrayList
// markerPoints.add(point);
//
// // Creating MarkerOptions
// MarkerOptions options = new MarkerOptions();
//
// // Setting the position of the marker
// options.position(point);
//
// /**
// * For the start location, the color of marker is GREEN and
// * for the end location, the color of marker is RED.
// */
// if(markerPoints.size()==1){
// options.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN));
// }else if(markerPoints.size()==2){
// options.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_RED));
// }
//
//
// // Add new marker to the Google Map Android API V2
// map.addMarker(options);
//
// // Checks, whether start and end locations are captured
// if(markerPoints.size() >= 2){
// LatLng origin = markerPoints.get(0);
// LatLng dest = markerPoints.get(1);
//
// // Getting URL to the Google Directions API
// String url = getDirectionsUrl(origin, dest);
//
// DownloadTask downloadTask = new DownloadTask();
//
// // Start downloading json data from Google Directions API
// downloadTask.execute(url);
// }
//
// }
// });
}
private void sourceTodestination() {
// Source
LatLng point = new LatLng(sourceLatitude, sourceLongitude);
// Destination
double destLatitude = 23.7383;
double destLongitude = 90.3958;
LatLng point1 = new LatLng(destLatitude, destLongitude);
CameraUpdate center=
CameraUpdateFactory.newLatLng(new LatLng((sourceLatitude + destLatitude)/2, (sourceLongitude + destLongitude)/2));
CameraUpdate zoom=CameraUpdateFactory.zoomTo(13);
map.moveCamera(center);
map.animateCamera(zoom);
// Adding new item to the ArrayList
markerPoints.add(point);
markerPoints.add(point1);
// Creating MarkerOptions
MarkerOptions options = new MarkerOptions();
// Setting the position of the marker
options.position(point);
/**
* For the start location, the color of marker is GREEN and
* for the end location, the color of marker is RED.
*/
options.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN));
MarkerOptions options1 = new MarkerOptions();
options1.position(point1);
options1.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_RED));
// Add new marker to the Google Map Android API V2
map.addMarker(options);
map.addMarker(options1);
// Checks, whether start and end locations are captured
if(markerPoints.size() >= 2){
LatLng origin = markerPoints.get(0);
LatLng dest = markerPoints.get(1);
// Getting URL to the Google Directions API
String url = getDirectionsUrl(origin, dest);
DownloadTask downloadTask = new DownloadTask();
// Start downloading json data from Google Directions API
downloadTask.execute(url);
}
}
private String getDirectionsUrl(LatLng origin,LatLng dest){
// Origin of route
String str_origin = "origin="+origin.latitude+","+origin.longitude;
// Destination of route
String str_dest = "destination="+dest.latitude+","+dest.longitude;
// Sensor enabled
String sensor = "sensor=false";
// Building the parameters to the web service
String parameters = str_origin+"&"+str_dest+"&"+sensor;
// Output format
String output = "json";
// Building the url to the web service
String url = "https://maps.googleapis.com/maps/api/directions/"+output+"?"+parameters;
return url;
}
/** A method to download json data from url */
private String downloadUrl(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();
br.close();
}catch(Exception e){
Log.d("Exception while downloading url", e.toString());
}finally{
iStream.close();
urlConnection.disconnect();
}
return data;
}
// Fetches data from url passed
private class DownloadTask extends AsyncTask<String, Void, String>{
// Downloading data in non-ui thread
@Override
protected String doInBackground(String... url) {
// For storing data from web service
String data = "";
try{
// Fetching the data from web service
data = downloadUrl(url[0]);
}catch(Exception e){
Log.d("Background Task",e.toString());
}
return data;
}
// Executes in UI thread, after the execution of
// doInBackground()
@Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
ParserTask parserTask = new ParserTask();
// Invokes the thread for parsing the JSON data
parserTask.execute(result);
}
}
/** A class to parse the Google Places in JSON format */
private class ParserTask extends AsyncTask<String, Integer, List<List<HashMap<String,String>>> >{
// Parsing the data in non-ui thread
@Override
protected List<List<HashMap<String, String>>> doInBackground(String... jsonData) {
JSONObject jObject;
List<List<HashMap<String, String>>> routes = null;
try{
jObject = new JSONObject(jsonData[0]);
DirectionsJSONParser parser = new DirectionsJSONParser();
// Starts parsing data
routes = parser.parse(jObject);
}catch(Exception e){
e.printStackTrace();
}
return routes;
}
// Executes in UI thread, after the parsing process
@Override
protected void onPostExecute(List<List<HashMap<String, String>>> result) {
ArrayList<LatLng> points = null;
PolylineOptions lineOptions = null;
MarkerOptions markerOptions = new MarkerOptions();
// Traversing through all the routes
for(int i=0;i<result.size();i++){
points = new ArrayList<LatLng>();
lineOptions = new PolylineOptions();
// Fetching i-th route
List<HashMap<String, String>> path = result.get(i);
// Fetching all the points in i-th route
for(int j=0;j<path.size();j++){
HashMap<String,String> point = path.get(j);
double lat = Double.parseDouble(point.get("lat"));
double lng = Double.parseDouble(point.get("lng"));
LatLng position = new LatLng(lat, lng);
points.add(position);
}
// Adding all the points in the route to LineOptions
lineOptions.addAll(points);
lineOptions.width(2);
lineOptions.color(Color.RED);
}
// Drawing polyline in the Google Map for the i-th route
map.addPolyline(lineOptions);
}
}
/* Class My Location Listener */
public class MyLocationListener implements LocationListener {
public void onLocationChanged(Location loc) {
sourceLatitude = loc.getLatitude();
sourceLongitude = loc.getLongitude();
sourceTodestination();
Toast.makeText(getApplicationContext(), sourceLatitude + " - " + sourceLongitude,
Toast.LENGTH_SHORT).show();
}
public void onProviderDisabled(String provider) {
Toast.makeText(getApplicationContext(), "Gps Disabled",
Toast.LENGTH_SHORT).show();
}
public void onProviderEnabled(String provider) {
android.util.Log.v("", "Latitud = ");
Toast.makeText(getApplicationContext(), "Gps Enabled",
Toast.LENGTH_SHORT).show();
}
public void onStatusChanged(String provider, int status, Bundle extras) {
android.util.Log.v("", "status = ");
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
JSON Parser
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import com.google.android.gms.maps.model.LatLng;
public class DirectionsJSONParser {
/** Receives a JSONObject and returns a list of lists containing latitude and longitude */
public List<List<HashMap<String,String>>> parse(JSONObject jObject){
List<List<HashMap<String, String>>> routes = new ArrayList<List<HashMap<String,String>>>() ;
JSONArray jRoutes = null;
JSONArray jLegs = null;
JSONArray jSteps = null;
try {
jRoutes = jObject.getJSONArray("routes");
/** Traversing all routes */
for(int i=0;i<jRoutes.length();i++){
jLegs = ( (JSONObject)jRoutes.get(i)).getJSONArray("legs");
List path = new ArrayList<HashMap<String, String>>();
/** Traversing all legs */
for(int j=0;j<jLegs.length();j++){
jSteps = ( (JSONObject)jLegs.get(j)).getJSONArray("steps");
/** Traversing all steps */
for(int k=0;k<jSteps.length();k++){
String polyline = "";
polyline = (String)((JSONObject)((JSONObject)jSteps.get(k)).get("polyline")).get("points");
List<LatLng> list = decodePoly(polyline);
/** Traversing all points */
for(int l=0;l<list.size();l++){
HashMap<String, String> hm = new HashMap<String, String>();
hm.put("lat", Double.toString(((LatLng)list.get(l)).latitude) );
hm.put("lng", Double.toString(((LatLng)list.get(l)).longitude) );
path.add(hm);
}
}
routes.add(path);
}
}
} catch (JSONException e) {
e.printStackTrace();
}catch (Exception e){
}
return routes;
}
/**
* Method to decode polyline points
* Courtesy : http://jeffreysambells.com/2010/05/27/decoding-polylines-from-google-maps-direction-api-with-java
* */
private List<LatLng> decodePoly(String encoded) {
List<LatLng> poly = new ArrayList<LatLng>();
int index = 0, len = encoded.length();
int lat = 0, lng = 0;
while (index < len) {
int b, shift = 0, result = 0;
do {
b = encoded.charAt(index++) - 63;
result |= (b & 0x1f) << shift;
shift += 5;
} while (b >= 0x20);
int dlat = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
lat += dlat;
shift = 0;
result = 0;
do {
b = encoded.charAt(index++) - 63;
result |= (b & 0x1f) << shift;
shift += 5;
} while (b >= 0x20);
int dlng = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
lng += dlng;
LatLng p = new LatLng((((double) lat / 1E5)),
(((double) lng / 1E5)));
poly.add(p);
}
return poly;
}
}
请原谅我的无知，但我无法弄清楚如何使用这两种方法。任何提示赞赏！谢谢 编辑：更多细节，我只能让这个工作显示位置，但我不能让它显示我当前的位置和路线到那些目的地
答案 0 :(得分：0)
您当前的位置是此方法的位置
public void onLocationChanged(Location loc)
将准确度应用于您的位置以获得准确的位置。准确度阈值取决于您。不到30米就好了。