我开发了一个应用程序，用于绘制起点和目的地之间的路线，用户也可以沿着该路径标记一些路标，并且路线将被正确绘制。但是我只能在地图上标记2个位置时才能获得距离。如果我标记2,3个位置它将不会给我距离。这些是我的代码，
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;
JSONObject jDistance = null;
JSONObject jDuration = 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++){
/** Getting distance from the json data */
jDistance = ((JSONObject) jLegs.get(j)).getJSONObject("distance");
HashMap<String, String> hmDistance = new HashMap<String, String>();
hmDistance.put("distance", jDistance.getString("text"));
/** Getting duration from the json data */
jDuration = ((JSONObject) jLegs.get(j)).getJSONObject("duration");
HashMap<String, String> hmDuration = new HashMap<String, String>();
hmDuration.put("duration", jDuration.getString("text"));
/** Adding distance object to the path */
path.add(hmDistance);
/** Adding duration object to the path */
path.add(hmDuration);
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 : 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;
}
}
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("Error 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();
String distance = "";
String duration = "";
if(result.size()<1){
Toast.makeText(getBaseContext(), "No Points", Toast.LENGTH_SHORT).show();
return;
}
// 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);
if(j==0){ // Get distance from the list
distance = (String)point.get("distance");
continue;
}else if(j==1){ // Get duration from the list
duration = (String)point.get("duration");
continue;
}
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);
}
tvDistanceDuration.setText("Distance:"+distance + ", Duration:"+duration);
// Drawing polyline in the Google Map for the i-th route
map.addPolyline(lineOptions);
}
}
我以前要求的网址
String parameters = str_origin+"&"+str_dest+"&"+sensor+"&"+waypoints;
// Output format
String output = "json";
// Building the url to the web service
String url = "https://maps.googleapis.com/maps/api/directions/"+output+"?"+parameters;
Error I found when I used 4 points with 2 way points
这是在线上的onPostExecute方法，
double lat = Double.parseDouble(point.get("lat"));
double lng = Double.parseDouble(point.get("lng"));
LatLng position = new LatLng(lat, lng);
我在这里做错了什么？
答案 0 :(得分：1)
你应该通过改造来尝试这个。
将此代码置于MainActivity中的按钮单击： -
<强> MainActivity.java
public class MainActivity extends AppCompatActivity implements AdapterView.OnItemClickListener, OnMapReadyCallback {
private static final String LOG_TAG = "TAG1";
private static final String KEY = "Enter Your Key";
String displayResponseSource = "";
String displayResponseDestination = "";
private Button btn_search;
private GoogleMap map;
private APIInterface apiInterface;
private SupportMapFragment mapFragment;
private AutoCompleteTextView autoCompViewSource;
private AutoCompleteTextView autoCompViewDestination;
private String autocompletetextSource = "";
private String autocompletetextDestination = "";
private LatLng maplocationdestination;
private LatLng maplocationsource;
private double longitudeSource;
private double latitudeSource;
private double latitudeDestination;
private double longitudeDestination;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
autoCompViewSource = (AutoCompleteTextView) findViewById(R.id.autoCompleteTextViewSource);
autoCompViewDestination = (AutoCompleteTextView) findViewById(R.id.autoCompleteTextViewDestination);
btn_search = (Button) findViewById(R.id.btn_search);
autoCompViewSource.setAdapter(new GooglePlacesAutocompleteAdapterSource(this, R.layout.lv_item));
autoCompViewSource.setOnItemClickListener(this);
autoCompViewDestination.setAdapter(new GooglePlacesAutocompleteAdapterDestination(this, R.layout.lv_item));
autoCompViewDestination.setOnItemClickListener(this);
mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
}
@Override
public void onMapReady(GoogleMap googleMap) {
map = googleMap;
btn_search.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
autocompletetextSource = autoCompViewSource.getText().toString();
autocompletetextDestination = autoCompViewDestination.getText().toString();
apiInterface = APIClient.getClient().create(APIInterface.class);
Call<ModelLatLong> call = apiInterface.getResponse(autocompletetextSource, KEY);
// autocompletetext,KEY
call.enqueue(new Callback<ModelLatLong>() {
@Override
public void onResponse(Call<ModelLatLong> call, Response<ModelLatLong> response) {
Log.i("TAG", response.code() + "");
ModelLatLong resource = response.body();
ArrayList<Results> resultsList = resource.getResults();
for (Results results : resultsList) {
longitudeSource = results.getGeometry().getLocation().getLng();
latitudeSource = results.getGeometry().getLocation().getLat();
Log.i("TAG1", displayResponseSource + "HI");
}
displayResponseSource = latitudeSource+ "," + longitudeSource;
// Toast.makeText(MainActivity.this, displayResponseSource, Toast.LENGTH_SHORT).show();
maplocationsource = new LatLng(latitudeSource, longitudeSource);
map.addMarker(new MarkerOptions()
.position(maplocationsource)
.snippet(autocompletetextSource)).showInfoWindow();
CameraUpdate center = CameraUpdateFactory.newLatLngZoom(maplocationsource, 14);
map.animateCamera(center);
}
@Override
public void onFailure(Call<ModelLatLong> call, Throwable t) {
Log.i("TAG1", "Failed");
call.cancel();
}
});
Call<ModelLatLong> calldes = apiInterface.getResponse(autocompletetextDestination, KEY);
// autocompletetext,KEY
calldes.enqueue(new Callback<ModelLatLong>() {
@Override
public void onResponse(Call<ModelLatLong> call, Response<ModelLatLong> response) {
Log.i("TAG", response.code() + "");
ModelLatLong resourcedes = response.body();
ArrayList<Results> resultsListdes = resourcedes.getResults();
for (Results results : resultsListdes) {
longitudeDestination = results.getGeometry().getLocation().getLng();
latitudeDestination = results.getGeometry().getLocation().getLat();
Log.i("TAG1", displayResponseDestination + "HI");
}
displayResponseDestination = latitudeDestination + "," + longitudeDestination;
// Toast.makeText(MainActivity.this, displayResponseDestination, Toast.LENGTH_SHORT).show();
maplocationdestination = new LatLng(latitudeDestination, longitudeDestination);
map.addMarker(new MarkerOptions()
.position(maplocationdestination)
.snippet(autocompletetextSource)).showInfoWindow();
CameraUpdate center = CameraUpdateFactory.newLatLngZoom(maplocationdestination, 14);
map.animateCamera(center);
}
@Override
public void onFailure(Call<ModelLatLong> call, Throwable t) {
Log.i("TAG1", "Failed");
call.cancel();
}
});
Call<ModelRoutes> calldistance = apiInterface.getResponseDistance(Get Your Source Latitude and Longitude Here(Eg. 20.9127766,73.7531254), Get Your Destination Latitude and Longitude Here in String(Eg. 23.0098149, 72.5035273), KEY);
calldistance.enqueue(new Callback<ModelRoutes>() {
@Override
public void onResponse(Call<ModelRoutes> call, Response<ModelRoutes> response) {
String displayResponse = "";
ModelRoutes resourcedis = response.body();
Log.i("TAG", response.code() + "Hello");
ArrayList<Routes> routesList = resourcedis.getRoutes();
for (Routes routes : routesList) {
ArrayList<Legs> legsList = routes.getLegs();
for (Legs legs : legsList) {
String killoMeter = legs.getDistance().getText();
double timeDistance = legs.getDistance().getValue();
displayResponse += "\n Killometer : " + killoMeter + "\n Time Duration : " + timeDistance + "\n";
Log.i("TAG1", displayResponse + "HI");
}
}
Toast.makeText(MainActivity.this, displayResponse, Toast.LENGTH_SHORT).show();
}
@Override
public void onFailure(Call<ModelRoutes> call, Throwable t) {
Log.i("TAG1", "Failed");
call.cancel();
}
});
}
});
}
public void onItemClick(AdapterView adapterView, View view, int position, long id) {
String str = (String) adapterView.getItemAtPosition(position);
// Toast.makeText(this, str, Toast.LENGTH_SHORT).show();
}
public static ArrayList autocomplete(String input) {
ArrayList resultList = null;
HttpURLConnection conn = null;
StringBuilder jsonResults = new StringBuilder();
try {
StringBuilder sb = new StringBuilder("https://maps.googleapis.com/maps/api/place/autocomplete/json");
sb.append("?key=Enter Your Key Here");
sb.append("&input=" + URLEncoder.encode(input, "utf8"));
URL url = new URL(sb.toString());
conn = (HttpURLConnection) url.openConnection();
InputStreamReader in = new InputStreamReader(conn.getInputStream());
int read;
char[] buff = new char[1024];
while ((read = in.read(buff)) != -1) {
jsonResults.append(buff, 0, read);
}
} catch (MalformedURLException e) {
Log.e(LOG_TAG, "Error processing Places API URL", e);
return resultList;
} catch (IOException e) {
Log.e(LOG_TAG, "Error connecting to Places API", e);
return resultList;
} finally {
if (conn != null) {
conn.disconnect();
}
}
try {
JSONObject jsonObj = new JSONObject(jsonResults.toString());
JSONArray predsJsonArray = jsonObj.getJSONArray("predictions");
resultList = new ArrayList(predsJsonArray.length());
for (int i = 0; i < predsJsonArray.length(); i++) {
System.out.println(predsJsonArray.getJSONObject(i).getString("description"));
resultList.add(predsJsonArray.getJSONObject(i).getString("description"));
}
} catch (JSONException e) {
Log.e(LOG_TAG, "Cannot process JSON results", e);
}
return resultList;
}
class GooglePlacesAutocompleteAdapterSource extends ArrayAdapter implements Filterable {
private ArrayList resultList;
public GooglePlacesAutocompleteAdapterSource(Context context, int textViewResourceId) {
super(context, textViewResourceId);
}
@Override
public int getCount() {
return resultList.size();
}
@Override
public Object getItem(int index) {
return resultList.get(index);
}
@Override
public Filter getFilter() {
Filter filter = new Filter() {
@Override
protected FilterResults performFiltering(CharSequence constraint) {
FilterResults filterResults = new FilterResults();
if (constraint != null) {
resultList = autocomplete(constraint.toString());
filterResults.values = resultList;
filterResults.count = resultList.size();
}
return filterResults;
}
@Override
protected void publishResults(CharSequence constraint, Filter.FilterResults results) {
if (results != null && results.count > 0) {
notifyDataSetChanged();
} else {
notifyDataSetInvalidated();
}
}
};
return filter;
}
}
class GooglePlacesAutocompleteAdapterDestination extends ArrayAdapter implements Filterable {
private ArrayList resultList;
public GooglePlacesAutocompleteAdapterDestination(Context context, int textViewResourceId) {
super(context, textViewResourceId);
}
@Override
public int getCount() {
return resultList.size();
}
@Override
public Object getItem(int index) {
return resultList.get(index);
}
@Override
public Filter getFilter() {
Filter filter = new Filter() {
@Override
protected FilterResults performFiltering(CharSequence constraint) {
FilterResults filterResults = new FilterResults();
if (constraint != null) {
resultList = autocomplete(constraint.toString());
filterResults.values = resultList;
filterResults.count = resultList.size();
}
return filterResults;
}
@Override
protected void publishResults(CharSequence constraint, Filter.FilterResults results) {
if (results != null && results.count > 0) {
notifyDataSetChanged();
} else {
notifyDataSetInvalidated();
}
}
};
return filter;
}
}
}
<强> ModelRoutes.java
public class ModelRoutes extends Legs {
ArrayList<Routes> routes = null;
public ArrayList<Routes> getRoutes() {
return routes;
}
public void setRoutes(ArrayList<Routes> routes) {
this.routes = routes;
}
}
<强> Routes.java
public class Routes extends Legs{
ArrayList<Legs> legs = null;
public ArrayList<Legs> getLegs() {
return legs;
}
public void setLegs(ArrayList<Legs> legs) {
this.legs = legs;
}
}
<强> Legs.java
public class Legs {
Distances distance;
Durations duration;
public Distances getDistance() {
return distance;
}
public void setDistance(Distances distance) {
this.distance = distance;
}
public Durations getDuration() {
return duration;
}
public void setDuration(Durations duration) {
this.duration = duration;
}
public class Distances{
public String getText() {
return text;
}
public void setText(String text) {
this.text = text;
}
public double getValue() {
return value;
}
public void setValue(double value) {
this.value = value;
}
String text;
double value;
}
public class Durations{
String text;
double value;
public String getText() {
return text;
}
public void setText(String text) {
this.text = text;
}
public double getValue() {
return value;
}
public void setValue(double value) {
this.value = value;
}
}
}
<强> APIClient.java
public class APIClient {
private static Retrofit retrofit = null;
static Retrofit getClient() {
HttpLoggingInterceptor interceptor = new HttpLoggingInterceptor();
interceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
OkHttpClient client = new OkHttpClient.Builder().addInterceptor(interceptor).build();
retrofit = new Retrofit.Builder()
.baseUrl("https://maps.googleapis.com")
.addConverterFactory(GsonConverterFactory.create())
.client(client)
.build();
return retrofit;
}
}
<强> APIInterface.java
public interface APIInterface {
@GET("/maps/api/geocode/json")
Call<ModelLatLong> getResponse(
@Query("address") String str,
@Query("key") String str2);
@GET("/maps/api/directions/json")
Call<ModelRoutes> getResponseDistance(
@Query("origin") String str,
@Query("destination") String str1,
@Query("key") String str2);
}
<强> ModelLatLong.java
public class ModelLatLong extends Results {
private ArrayList<Results> results=null;
public ArrayList<Results> getResults() {
return results;
}
public void setResults(ArrayList<Results> results) {
this.results = results;
}
}
<强> Results.java
public class Results extends Geometry{
private Geometry geometry;
public Geometry getGeometry() {
return this.geometry;
}
public void setGeometry(Geometry geometry) {
this.geometry = geometry;
}
}
<强> Geometry.java
public class Geometry extends Location{
private Location location;
public Location getLocation() {
return this.location;
}
public void setLocation(Location location) {
this.location = location;
}
}
<强> Location.java
public class Location {
private double lat;
private double lng;
public double getLat() {
return lat;
}
public void setLat(double lat) {
this.lat = lat;
}
public double getLng() {
return lng;
}
public void setLng(double lng) {
this.lng = lng;
}
}
<强> activity_main.xml中
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.gmapplaceapi.MainActivity">
<AutoCompleteTextView
android:id="@+id/autoCompleteTextViewSource"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10"
android:hint="Please enter Source place"
>
<requestFocus />
</AutoCompleteTextView>
<AutoCompleteTextView
android:id="@+id/autoCompleteTextViewDestination"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10"
android:layout_below="@+id/autoCompleteTextViewSource"
android:hint="Please enter Destination place"
>
<requestFocus />
</AutoCompleteTextView>
<Button
android:id="@+id/btn_search"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Search"
android:layout_below="@+id/autoCompleteTextViewDestination"/>
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
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="fill_parent"
android:layout_below="@+id/btn_search"
tools:context="com.example.mapwithmarker.MapsMarkerActivity" />
</RelativeLayout>
<强> lv_item.xml
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="3dp"
android:textSize="20dp" />
不要忘记将Internet权限放在清单文件中。