最近的 hospital/restaurant 的 MapActivity 查询不起作用
MapActivity query for nearest hospital/restaurant not working
编辑：已解决！除了 Daniel 的回答（救了我的命），这是我所做的：
1. 将 'MapActivity2' class 替换为服务器 API 键。
2.让清单中的其他键和'maps_activites.xml。成为 android API 键
3. 在 Google Developer APIS:
上启用以下 APIS
Google 地图 Android API
Google 为 Android
放置 API
Google 地点 API 网络服务
4. 砰！有效。无论如何，这是我的 github 存储库的代码：
https://github.com/bholagabbar/AurumHealthApp
我正在尝试检索离我当前位置最近的餐馆。我正在使用我在网上找到的代码 here。但是我收到以下错误。我已将整个 logcat 用于执行，并以粗体突出显示错误：
11-30 04:53:31.000 25292-25292/? I/art: Late-enabling -Xcheck:jni
11-30 04:53:31.033 25292-25302/? I/art: Debugger is no longer active
<>11-30 04:53:31.100 25292-25311/? I/GMPM: App measurement is starting up
11-30 04:53:31.109 25292-25311/? E/GMPM: getGoogleAppId failed with status: 10
11-30 04:53:31.111 25292-25311/? E/GMPM: Uploading is not possible. App measurement disabled
11-30 04:53:31.125 25292-25314/? D/OpenGLRenderer: Use EGL_SWAP_BEHAVIOR_PRESERVED: true`11-30 04:53:31.135 25292-25292/? D/Atlas: Validating map...
11-30 04:53:31.178 25292-25314/? I/Adreno-EGL: : EGL 1.4 QUALCOMM build: (Ibddc658e36)
11-30 04:53:31.178 25292-25314/? I/Adreno-EGL: OpenGL ES Shader Compiler Version: E031.25.03.04
11-30 04:53:31.178 25292-25314/? I/Adreno-EGL: Build Date: 08/10/15 Mon
11-30 04:53:31.178 25292-25314/? I/Adreno-EGL: Local Branch: workspace
11-30 04:53:31.178 25292-25314/? I/Adreno-EGL: Remote Branch:
11-30 04:53:31.178 25292-25314/? I/Adreno-EGL: Local Patches:
11-30 04:53:31.178 25292-25314/? I/Adreno-EGL: Reconstruct Branch:
11-30 04:53:31.179 25292-25314/? I/OpenGLRenderer: Initialized EGL, version 1.4
11-30 04:53:31.193 25292-25314/? D/OpenGLRenderer: Enabling debug mode 0
11-30 04:53:32.663 25292-25292/com.iotaconcepts.aurum I/Choreographer: Skipped 37 frames! The application may be doing too much work on its main thread.
11-30 04:53:32.737 25292-25314/com.iotaconcepts.aurum V/RenderScript: Application requested CPU execution
11-30 04:53:32.747 25292-25314/com.iotaconcepts.aurum V/RenderScript: 0xb7f96960 Launching thread(s), CPUs 4
11-30 04:53:36.092 25292-25292/com.iotaconcepts.aurum D/AndroidRuntime: Shutting down VM
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: FATAL EXCEPTION: main
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: Process: com.iotaconcepts.aurum, PID: 25292
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: java.lang.RuntimeException: Unable to start activity ComponentInfo{com.iotaconcepts.aurum/com.iotaconcepts.aurum.MapsActivity2}: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.maps.SupportMapFragment.getMapAsync(com.google.android.gms.maps.OnMapReadyCallback)' on a null object reference
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2339)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2413)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.access0(ActivityThread.java:155)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1317)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:102)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.os.Looper.loop(Looper.java:135)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:5343)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at java.lang.reflect.Method.invoke(Native Method)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:372)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:907)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:702)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.maps.SupportMapFragment.getMapAsync(com.google.android.gms.maps.OnMapReadyCallback)' on a null object reference
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at com.iotaconcepts.aurum.MapsActivity2.onCreate(MapsActivity2.java:42)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.Activity.performCreate(Activity.java:6010)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1129)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2292)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2413)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.access0(ActivityThread.java:155)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1317)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:102)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.os.Looper.loop(Looper.java:135)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:5343)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at java.lang.reflect.Method.invoke(Native Method)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:372)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:907)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:702)
在过去的 2 个小时里，我一直在失去理智，试图找出我们的错误，但徒劳无功。这是 activity:
的代码
编辑 修复后，这里是代码
包 com.iotaconcepts.aurum;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
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.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
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;
public class MapsActivity2 extends AppCompatActivity implements OnMapReadyCallback
{
private GoogleMap mGoogleMap;
SupportMapFragment mapFrag;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mapFrag = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
mapFrag.getMapAsync(this);
}
@Override
public void onMapReady(GoogleMap googleMap)
{
mGoogleMap=googleMap;
mGoogleMap.setMyLocationEnabled(true);
StringBuilder sbValue = new StringBuilder(sbMethod());
PlacesTask placesTask = new PlacesTask();
placesTask.execute(sbValue.toString());
}
public StringBuilder sbMethod()
{
//use your current location here
double mLatitude = 37.77657;
double mLongitude = -122.417506;
StringBuilder sb = new StringBuilder("https://maps.googleapis.com/maps/api/place/nearbysearch/json?");
sb.append("location=" + mLatitude + "," + mLongitude);
sb.append("&radius=5000");
sb.append("&types=" + "restaurant");
sb.append("&sensor=true");
sb.append("&key=AIza************************");
Log.d("Map", "url: " + sb.toString());
return sb;
}
private class PlacesTask extends AsyncTask<String, Integer, String>
{
String data = null;
// Invoked by execute() method of this object
@Override
protected String doInBackground(String... url) {
try {
data = downloadUrl(url[0]);
} catch (Exception e) {
Log.d("Background Task", e.toString());
}
return data;
}
// Executed after the complete execution of doInBackground() method
@Override
protected void onPostExecute(String result) {
ParserTask parserTask = new ParserTask();
// Start parsing the Google places in JSON format
// Invokes the "doInBackground()" method of the class ParserTask
parserTask.execute(result);
}
}
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", e.toString());
} finally {
iStream.close();
urlConnection.disconnect();
}
return data;
}
private class ParserTask extends AsyncTask<String, Integer, List<HashMap<String, String>>> {
JSONObject jObject;
// Invoked by execute() method of this object
@Override
protected List<HashMap<String, String>> doInBackground(String... jsonData) {
List<HashMap<String, String>> places = null;
Place_JSON placeJson = new Place_JSON();
try {
jObject = new JSONObject(jsonData[0]);
places = placeJson.parse(jObject);
} catch (Exception e) {
Log.d("Exception", e.toString());
}
return places;
}
// Executed after the complete execution of doInBackground() method
@Override
protected void onPostExecute(List<HashMap<String, String>> list) {
Log.d("Map", "list size: " + list.size());
// Clears all the existing markers;
mGoogleMap.clear();
for (int i = 0; i < list.size(); i++) {
// Creating a marker
MarkerOptions markerOptions = new MarkerOptions();
// Getting a place from the places list
HashMap<String, String> hmPlace = list.get(i);
// Getting latitude of the place
double lat = Double.parseDouble(hmPlace.get("lat"));
// Getting longitude of the place
double lng = Double.parseDouble(hmPlace.get("lng"));
// Getting name
String name = hmPlace.get("place_name");
Log.d("Map", "place: " + name);
// Getting vicinity
String vicinity = hmPlace.get("vicinity");
LatLng latLng = new LatLng(lat, lng);
// Setting the position for the marker
markerOptions.position(latLng);
markerOptions.title(name + " : " + vicinity);
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
// Placing a marker on the touched position
Marker m = mGoogleMap.addMarker(markerOptions);
}
}
}
public class Place_JSON {
/**
* Receives a JSONObject and returns a list
*/
public List<HashMap<String, String>> parse(JSONObject jObject) {
JSONArray jPlaces = null;
try {
/** Retrieves all the elements in the 'places' array */
jPlaces = jObject.getJSONArray("results");
} catch (JSONException e) {
e.printStackTrace();
}
/** Invoking getPlaces with the array of json object
* where each json object represent a place
*/
return getPlaces(jPlaces);
}
private List<HashMap<String, String>> getPlaces(JSONArray jPlaces) {
int placesCount = jPlaces.length();
List<HashMap<String, String>> placesList = new ArrayList<HashMap<String, String>>();
HashMap<String, String> place = null;
/** Taking each place, parses and adds to list object */
for (int i = 0; i < placesCount; i++) {
try {
/** Call getPlace with place JSON object to parse the place */
place = getPlace((JSONObject) jPlaces.get(i));
placesList.add(place);
} catch (JSONException e) {
e.printStackTrace();
}
}
return placesList;
}
/**
* Parsing the Place JSON object
*/
private HashMap<String, String> getPlace(JSONObject jPlace)
{
HashMap<String, String> place = new HashMap<String, String>();
String placeName = "-NA-";
String vicinity = "-NA-";
String latitude = "";
String longitude = "";
String reference = "";
try {
// Extracting Place name, if available
if (!jPlace.isNull("name")) {
placeName = jPlace.getString("name");
}
// Extracting Place Vicinity, if available
if (!jPlace.isNull("vicinity")) {
vicinity = jPlace.getString("vicinity");
}
latitude = jPlace.getJSONObject("geometry").getJSONObject("location").getString("lat");
longitude = jPlace.getJSONObject("geometry").getJSONObject("location").getString("lng");
reference = jPlace.getString("reference");
place.put("place_name", placeName);
place.put("vicinity", vicinity);
place.put("lat", latitude);
place.put("lng", longitude);
place.put("reference", reference);
} catch (JSONException e) {
e.printStackTrace();
}
return place;
}
}
}
XML 文件是：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:map="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/map"
tools:context="com.iotaconcepts.aurum.MapsActivity2"
android:name="com.google.android.gms.maps.SupportMapFragment"/>
</LinearLayout>
清单文件：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.iotaconcepts.aurum" >
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-library android:name="com.google.android.maps" />
<!-- uses-permission android:name="android.permission.INTERNET" / -->
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:theme="@style/MyMaterialTheme" >
<activity
android:name=".MainActivity"
android:label="Aurum" >
<intent-filter>
<action android:name="android.intent.action.MAINACTIVITY" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
<activity
android:name=".LoginActivity"
android:label="Aurum"
android:theme="@style/ColorfulActionBarTheme" >
<intent-filter>
<action android:name="android.intent.action.LOGIN" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
<activity
android:name=".Splash"
android:label="Aurum"
android:theme="@style/ColorfulActionBarTheme" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".Diagnosis"
android:label="Aurum"
android:theme="@style/Theme.Transparent" >
<intent-filter>
<action android:name="android.intent.action.DIAGNOSIS" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
<!--
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="AIza*************************" />
<activity
android:name=".MapsActivity2"
android:label="@string/title_activity_maps2" >
</activity>
<activity android:name=".testactivity" >
</activity>
</application>
</manifest>
我只是 运行 你的代码并让它工作。看起来主要问题是 key 和查询 url.
中的 api 键之间有一个 space
您也没有任何调用 getMapAsync() 的代码，因此您没有获得地图参考，并且 onMapReady() 不会被调用。
此外，请务必将服务器 API 密钥用于 Places Web API。
这是对我有用的代码：
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
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.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
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;
public class MapsActivity2 extends AppCompatActivity implements OnMapReadyCallback
{
private GoogleMap mGoogleMap;
SupportMapFragment mapFrag;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
//Wrong one:
//setContentView(R.layout.activity_main);
//Use this one:
setContentView(R.layout.activity_maps2);
mapFrag = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
mapFrag.getMapAsync(this);
}
@Override
public void onMapReady(GoogleMap googleMap)
{
mGoogleMap=googleMap;
mGoogleMap.setMyLocationEnabled(true);
StringBuilder sbValue = new StringBuilder(sbMethod());
PlacesTask placesTask = new PlacesTask();
placesTask.execute(sbValue.toString());
}
public StringBuilder sbMethod()
{
//use your current location here
double mLatitude = 37.77657;
double mLongitude = -122.417506;
StringBuilder sb = new StringBuilder("https://maps.googleapis.com/maps/api/place/nearbysearch/json?");
sb.append("location=" + mLatitude + "," + mLongitude);
sb.append("&radius=5000");
sb.append("&types=" + "restaurant");
sb.append("&sensor=true");
sb.append("&key=AIza******************************");
Log.d("Map", "url: " + sb.toString());
return sb;
}
private class PlacesTask extends AsyncTask<String, Integer, String>
{
String data = null;
// Invoked by execute() method of this object
@Override
protected String doInBackground(String... url) {
try {
data = downloadUrl(url[0]);
} catch (Exception e) {
Log.d("Background Task", e.toString());
}
return data;
}
// Executed after the complete execution of doInBackground() method
@Override
protected void onPostExecute(String result) {
ParserTask parserTask = new ParserTask();
// Start parsing the Google places in JSON format
// Invokes the "doInBackground()" method of the class ParserTask
parserTask.execute(result);
}
}
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", e.toString());
} finally {
iStream.close();
urlConnection.disconnect();
}
return data;
}
private class ParserTask extends AsyncTask<String, Integer, List<HashMap<String, String>>> {
JSONObject jObject;
// Invoked by execute() method of this object
@Override
protected List<HashMap<String, String>> doInBackground(String... jsonData) {
List<HashMap<String, String>> places = null;
Place_JSON placeJson = new Place_JSON();
try {
jObject = new JSONObject(jsonData[0]);
places = placeJson.parse(jObject);
} catch (Exception e) {
Log.d("Exception", e.toString());
}
return places;
}
// Executed after the complete execution of doInBackground() method
@Override
protected void onPostExecute(List<HashMap<String, String>> list) {
Log.d("Map", "list size: " + list.size());
// Clears all the existing markers;
mGoogleMap.clear();
for (int i = 0; i < list.size(); i++) {
// Creating a marker
MarkerOptions markerOptions = new MarkerOptions();
// Getting a place from the places list
HashMap<String, String> hmPlace = list.get(i);
// Getting latitude of the place
double lat = Double.parseDouble(hmPlace.get("lat"));
// Getting longitude of the place
double lng = Double.parseDouble(hmPlace.get("lng"));
// Getting name
String name = hmPlace.get("place_name");
Log.d("Map", "place: " + name);
// Getting vicinity
String vicinity = hmPlace.get("vicinity");
LatLng latLng = new LatLng(lat, lng);
// Setting the position for the marker
markerOptions.position(latLng);
markerOptions.title(name + " : " + vicinity);
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
// Placing a marker on the touched position
Marker m = mGoogleMap.addMarker(markerOptions);
}
}
}
public class Place_JSON {
/**
* Receives a JSONObject and returns a list
*/
public List<HashMap<String, String>> parse(JSONObject jObject) {
JSONArray jPlaces = null;
try {
/** Retrieves all the elements in the 'places' array */
jPlaces = jObject.getJSONArray("results");
} catch (JSONException e) {
e.printStackTrace();
}
/** Invoking getPlaces with the array of json object
* where each json object represent a place
*/
return getPlaces(jPlaces);
}
private List<HashMap<String, String>> getPlaces(JSONArray jPlaces) {
int placesCount = jPlaces.length();
List<HashMap<String, String>> placesList = new ArrayList<HashMap<String, String>>();
HashMap<String, String> place = null;
/** Taking each place, parses and adds to list object */
for (int i = 0; i < placesCount; i++) {
try {
/** Call getPlace with place JSON object to parse the place */
place = getPlace((JSONObject) jPlaces.get(i));
placesList.add(place);
} catch (JSONException e) {
e.printStackTrace();
}
}
return placesList;
}
/**
* Parsing the Place JSON object
*/
private HashMap<String, String> getPlace(JSONObject jPlace)
{
HashMap<String, String> place = new HashMap<String, String>();
String placeName = "-NA-";
String vicinity = "-NA-";
String latitude = "";
String longitude = "";
String reference = "";
try {
// Extracting Place name, if available
if (!jPlace.isNull("name")) {
placeName = jPlace.getString("name");
}
// Extracting Place Vicinity, if available
if (!jPlace.isNull("vicinity")) {
vicinity = jPlace.getString("vicinity");
}
latitude = jPlace.getJSONObject("geometry").getJSONObject("location").getString("lat");
longitude = jPlace.getJSONObject("geometry").getJSONObject("location").getString("lng");
reference = jPlace.getString("reference");
place.put("place_name", placeName);
place.put("vicinity", vicinity);
place.put("lat", latitude);
place.put("lng", longitude);
place.put("reference", reference);
} catch (JSONException e) {
e.printStackTrace();
}
return place;
}
}
}
activity_maps2.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:map="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/map"
tools:context="com.iotaconcepts.aurum.MapsActivity2"
android:name="com.google.android.gms.maps.SupportMapFragment"/>
</LinearLayout>
结果：
编辑：已解决！除了 Daniel 的回答（救了我的命），这是我所做的：
1. 将 'MapActivity2' class 替换为服务器 API 键。
2.让清单中的其他键和'maps_activites.xml。成为 android API 键
3. 在 Google Developer APIS:
上启用以下 APIS
Google 地图 Android API
Google 为 Android
放置 API
Google 地点 API 网络服务
4. 砰！有效。无论如何，这是我的 github 存储库的代码：
https://github.com/bholagabbar/AurumHealthApp
我正在尝试检索离我当前位置最近的餐馆。我正在使用我在网上找到的代码 here。但是我收到以下错误。我已将整个 logcat 用于执行，并以粗体突出显示错误：
11-30 04:53:31.000 25292-25292/? I/art: Late-enabling -Xcheck:jni
11-30 04:53:31.033 25292-25302/? I/art: Debugger is no longer active
<>11-30 04:53:31.100 25292-25311/? I/GMPM: App measurement is starting up
11-30 04:53:31.109 25292-25311/? E/GMPM: getGoogleAppId failed with status: 10
11-30 04:53:31.111 25292-25311/? E/GMPM: Uploading is not possible. App measurement disabled
11-30 04:53:31.125 25292-25314/? D/OpenGLRenderer: Use EGL_SWAP_BEHAVIOR_PRESERVED: true`11-30 04:53:31.135 25292-25292/? D/Atlas: Validating map...
11-30 04:53:31.178 25292-25314/? I/Adreno-EGL: : EGL 1.4 QUALCOMM build: (Ibddc658e36)
11-30 04:53:31.178 25292-25314/? I/Adreno-EGL: OpenGL ES Shader Compiler Version: E031.25.03.04
11-30 04:53:31.178 25292-25314/? I/Adreno-EGL: Build Date: 08/10/15 Mon
11-30 04:53:31.178 25292-25314/? I/Adreno-EGL: Local Branch: workspace
11-30 04:53:31.178 25292-25314/? I/Adreno-EGL: Remote Branch:
11-30 04:53:31.178 25292-25314/? I/Adreno-EGL: Local Patches:
11-30 04:53:31.178 25292-25314/? I/Adreno-EGL: Reconstruct Branch:
11-30 04:53:31.179 25292-25314/? I/OpenGLRenderer: Initialized EGL, version 1.4
11-30 04:53:31.193 25292-25314/? D/OpenGLRenderer: Enabling debug mode 0
11-30 04:53:32.663 25292-25292/com.iotaconcepts.aurum I/Choreographer: Skipped 37 frames! The application may be doing too much work on its main thread.
11-30 04:53:32.737 25292-25314/com.iotaconcepts.aurum V/RenderScript: Application requested CPU execution
11-30 04:53:32.747 25292-25314/com.iotaconcepts.aurum V/RenderScript: 0xb7f96960 Launching thread(s), CPUs 4
11-30 04:53:36.092 25292-25292/com.iotaconcepts.aurum D/AndroidRuntime: Shutting down VM
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: FATAL EXCEPTION: main
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: Process: com.iotaconcepts.aurum, PID: 25292
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: java.lang.RuntimeException: Unable to start activity ComponentInfo{com.iotaconcepts.aurum/com.iotaconcepts.aurum.MapsActivity2}: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.maps.SupportMapFragment.getMapAsync(com.google.android.gms.maps.OnMapReadyCallback)' on a null object reference
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2339)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2413)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.access0(ActivityThread.java:155)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1317)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:102)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.os.Looper.loop(Looper.java:135)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:5343)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at java.lang.reflect.Method.invoke(Native Method)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:372)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:907)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:702)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.maps.SupportMapFragment.getMapAsync(com.google.android.gms.maps.OnMapReadyCallback)' on a null object reference
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at com.iotaconcepts.aurum.MapsActivity2.onCreate(MapsActivity2.java:42)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.Activity.performCreate(Activity.java:6010)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1129)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2292)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2413)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.access0(ActivityThread.java:155)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1317)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:102)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.os.Looper.loop(Looper.java:135)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:5343)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at java.lang.reflect.Method.invoke(Native Method)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:372)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:907)
11-30 04:53:36.093 25292-25292/com.iotaconcepts.aurum E/AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:702)
在过去的 2 个小时里，我一直在失去理智，试图找出我们的错误，但徒劳无功。这是 activity:
的代码编辑 修复后，这里是代码
包 com.iotaconcepts.aurum;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
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.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
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;
public class MapsActivity2 extends AppCompatActivity implements OnMapReadyCallback
{
private GoogleMap mGoogleMap;
SupportMapFragment mapFrag;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mapFrag = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
mapFrag.getMapAsync(this);
}
@Override
public void onMapReady(GoogleMap googleMap)
{
mGoogleMap=googleMap;
mGoogleMap.setMyLocationEnabled(true);
StringBuilder sbValue = new StringBuilder(sbMethod());
PlacesTask placesTask = new PlacesTask();
placesTask.execute(sbValue.toString());
}
public StringBuilder sbMethod()
{
//use your current location here
double mLatitude = 37.77657;
double mLongitude = -122.417506;
StringBuilder sb = new StringBuilder("https://maps.googleapis.com/maps/api/place/nearbysearch/json?");
sb.append("location=" + mLatitude + "," + mLongitude);
sb.append("&radius=5000");
sb.append("&types=" + "restaurant");
sb.append("&sensor=true");
sb.append("&key=AIza************************");
Log.d("Map", "url: " + sb.toString());
return sb;
}
private class PlacesTask extends AsyncTask<String, Integer, String>
{
String data = null;
// Invoked by execute() method of this object
@Override
protected String doInBackground(String... url) {
try {
data = downloadUrl(url[0]);
} catch (Exception e) {
Log.d("Background Task", e.toString());
}
return data;
}
// Executed after the complete execution of doInBackground() method
@Override
protected void onPostExecute(String result) {
ParserTask parserTask = new ParserTask();
// Start parsing the Google places in JSON format
// Invokes the "doInBackground()" method of the class ParserTask
parserTask.execute(result);
}
}
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", e.toString());
} finally {
iStream.close();
urlConnection.disconnect();
}
return data;
}
private class ParserTask extends AsyncTask<String, Integer, List<HashMap<String, String>>> {
JSONObject jObject;
// Invoked by execute() method of this object
@Override
protected List<HashMap<String, String>> doInBackground(String... jsonData) {
List<HashMap<String, String>> places = null;
Place_JSON placeJson = new Place_JSON();
try {
jObject = new JSONObject(jsonData[0]);
places = placeJson.parse(jObject);
} catch (Exception e) {
Log.d("Exception", e.toString());
}
return places;
}
// Executed after the complete execution of doInBackground() method
@Override
protected void onPostExecute(List<HashMap<String, String>> list) {
Log.d("Map", "list size: " + list.size());
// Clears all the existing markers;
mGoogleMap.clear();
for (int i = 0; i < list.size(); i++) {
// Creating a marker
MarkerOptions markerOptions = new MarkerOptions();
// Getting a place from the places list
HashMap<String, String> hmPlace = list.get(i);
// Getting latitude of the place
double lat = Double.parseDouble(hmPlace.get("lat"));
// Getting longitude of the place
double lng = Double.parseDouble(hmPlace.get("lng"));
// Getting name
String name = hmPlace.get("place_name");
Log.d("Map", "place: " + name);
// Getting vicinity
String vicinity = hmPlace.get("vicinity");
LatLng latLng = new LatLng(lat, lng);
// Setting the position for the marker
markerOptions.position(latLng);
markerOptions.title(name + " : " + vicinity);
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
// Placing a marker on the touched position
Marker m = mGoogleMap.addMarker(markerOptions);
}
}
}
public class Place_JSON {
/**
* Receives a JSONObject and returns a list
*/
public List<HashMap<String, String>> parse(JSONObject jObject) {
JSONArray jPlaces = null;
try {
/** Retrieves all the elements in the 'places' array */
jPlaces = jObject.getJSONArray("results");
} catch (JSONException e) {
e.printStackTrace();
}
/** Invoking getPlaces with the array of json object
* where each json object represent a place
*/
return getPlaces(jPlaces);
}
private List<HashMap<String, String>> getPlaces(JSONArray jPlaces) {
int placesCount = jPlaces.length();
List<HashMap<String, String>> placesList = new ArrayList<HashMap<String, String>>();
HashMap<String, String> place = null;
/** Taking each place, parses and adds to list object */
for (int i = 0; i < placesCount; i++) {
try {
/** Call getPlace with place JSON object to parse the place */
place = getPlace((JSONObject) jPlaces.get(i));
placesList.add(place);
} catch (JSONException e) {
e.printStackTrace();
}
}
return placesList;
}
/**
* Parsing the Place JSON object
*/
private HashMap<String, String> getPlace(JSONObject jPlace)
{
HashMap<String, String> place = new HashMap<String, String>();
String placeName = "-NA-";
String vicinity = "-NA-";
String latitude = "";
String longitude = "";
String reference = "";
try {
// Extracting Place name, if available
if (!jPlace.isNull("name")) {
placeName = jPlace.getString("name");
}
// Extracting Place Vicinity, if available
if (!jPlace.isNull("vicinity")) {
vicinity = jPlace.getString("vicinity");
}
latitude = jPlace.getJSONObject("geometry").getJSONObject("location").getString("lat");
longitude = jPlace.getJSONObject("geometry").getJSONObject("location").getString("lng");
reference = jPlace.getString("reference");
place.put("place_name", placeName);
place.put("vicinity", vicinity);
place.put("lat", latitude);
place.put("lng", longitude);
place.put("reference", reference);
} catch (JSONException e) {
e.printStackTrace();
}
return place;
}
}
}
XML 文件是：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:map="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/map"
tools:context="com.iotaconcepts.aurum.MapsActivity2"
android:name="com.google.android.gms.maps.SupportMapFragment"/>
</LinearLayout>
清单文件：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.iotaconcepts.aurum" >
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-library android:name="com.google.android.maps" />
<!-- uses-permission android:name="android.permission.INTERNET" / -->
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:theme="@style/MyMaterialTheme" >
<activity
android:name=".MainActivity"
android:label="Aurum" >
<intent-filter>
<action android:name="android.intent.action.MAINACTIVITY" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
<activity
android:name=".LoginActivity"
android:label="Aurum"
android:theme="@style/ColorfulActionBarTheme" >
<intent-filter>
<action android:name="android.intent.action.LOGIN" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
<activity
android:name=".Splash"
android:label="Aurum"
android:theme="@style/ColorfulActionBarTheme" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".Diagnosis"
android:label="Aurum"
android:theme="@style/Theme.Transparent" >
<intent-filter>
<action android:name="android.intent.action.DIAGNOSIS" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
<!--
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="AIza*************************" />
<activity
android:name=".MapsActivity2"
android:label="@string/title_activity_maps2" >
</activity>
<activity android:name=".testactivity" >
</activity>
</application>
</manifest>
我只是 运行 你的代码并让它工作。看起来主要问题是 key 和查询 url.
您也没有任何调用 getMapAsync() 的代码，因此您没有获得地图参考，并且 onMapReady() 不会被调用。
此外，请务必将服务器 API 密钥用于 Places Web API。
这是对我有用的代码：
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
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.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
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;
public class MapsActivity2 extends AppCompatActivity implements OnMapReadyCallback
{
private GoogleMap mGoogleMap;
SupportMapFragment mapFrag;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
//Wrong one:
//setContentView(R.layout.activity_main);
//Use this one:
setContentView(R.layout.activity_maps2);
mapFrag = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
mapFrag.getMapAsync(this);
}
@Override
public void onMapReady(GoogleMap googleMap)
{
mGoogleMap=googleMap;
mGoogleMap.setMyLocationEnabled(true);
StringBuilder sbValue = new StringBuilder(sbMethod());
PlacesTask placesTask = new PlacesTask();
placesTask.execute(sbValue.toString());
}
public StringBuilder sbMethod()
{
//use your current location here
double mLatitude = 37.77657;
double mLongitude = -122.417506;
StringBuilder sb = new StringBuilder("https://maps.googleapis.com/maps/api/place/nearbysearch/json?");
sb.append("location=" + mLatitude + "," + mLongitude);
sb.append("&radius=5000");
sb.append("&types=" + "restaurant");
sb.append("&sensor=true");
sb.append("&key=AIza******************************");
Log.d("Map", "url: " + sb.toString());
return sb;
}
private class PlacesTask extends AsyncTask<String, Integer, String>
{
String data = null;
// Invoked by execute() method of this object
@Override
protected String doInBackground(String... url) {
try {
data = downloadUrl(url[0]);
} catch (Exception e) {
Log.d("Background Task", e.toString());
}
return data;
}
// Executed after the complete execution of doInBackground() method
@Override
protected void onPostExecute(String result) {
ParserTask parserTask = new ParserTask();
// Start parsing the Google places in JSON format
// Invokes the "doInBackground()" method of the class ParserTask
parserTask.execute(result);
}
}
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", e.toString());
} finally {
iStream.close();
urlConnection.disconnect();
}
return data;
}
private class ParserTask extends AsyncTask<String, Integer, List<HashMap<String, String>>> {
JSONObject jObject;
// Invoked by execute() method of this object
@Override
protected List<HashMap<String, String>> doInBackground(String... jsonData) {
List<HashMap<String, String>> places = null;
Place_JSON placeJson = new Place_JSON();
try {
jObject = new JSONObject(jsonData[0]);
places = placeJson.parse(jObject);
} catch (Exception e) {
Log.d("Exception", e.toString());
}
return places;
}
// Executed after the complete execution of doInBackground() method
@Override
protected void onPostExecute(List<HashMap<String, String>> list) {
Log.d("Map", "list size: " + list.size());
// Clears all the existing markers;
mGoogleMap.clear();
for (int i = 0; i < list.size(); i++) {
// Creating a marker
MarkerOptions markerOptions = new MarkerOptions();
// Getting a place from the places list
HashMap<String, String> hmPlace = list.get(i);
// Getting latitude of the place
double lat = Double.parseDouble(hmPlace.get("lat"));
// Getting longitude of the place
double lng = Double.parseDouble(hmPlace.get("lng"));
// Getting name
String name = hmPlace.get("place_name");
Log.d("Map", "place: " + name);
// Getting vicinity
String vicinity = hmPlace.get("vicinity");
LatLng latLng = new LatLng(lat, lng);
// Setting the position for the marker
markerOptions.position(latLng);
markerOptions.title(name + " : " + vicinity);
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
// Placing a marker on the touched position
Marker m = mGoogleMap.addMarker(markerOptions);
}
}
}
public class Place_JSON {
/**
* Receives a JSONObject and returns a list
*/
public List<HashMap<String, String>> parse(JSONObject jObject) {
JSONArray jPlaces = null;
try {
/** Retrieves all the elements in the 'places' array */
jPlaces = jObject.getJSONArray("results");
} catch (JSONException e) {
e.printStackTrace();
}
/** Invoking getPlaces with the array of json object
* where each json object represent a place
*/
return getPlaces(jPlaces);
}
private List<HashMap<String, String>> getPlaces(JSONArray jPlaces) {
int placesCount = jPlaces.length();
List<HashMap<String, String>> placesList = new ArrayList<HashMap<String, String>>();
HashMap<String, String> place = null;
/** Taking each place, parses and adds to list object */
for (int i = 0; i < placesCount; i++) {
try {
/** Call getPlace with place JSON object to parse the place */
place = getPlace((JSONObject) jPlaces.get(i));
placesList.add(place);
} catch (JSONException e) {
e.printStackTrace();
}
}
return placesList;
}
/**
* Parsing the Place JSON object
*/
private HashMap<String, String> getPlace(JSONObject jPlace)
{
HashMap<String, String> place = new HashMap<String, String>();
String placeName = "-NA-";
String vicinity = "-NA-";
String latitude = "";
String longitude = "";
String reference = "";
try {
// Extracting Place name, if available
if (!jPlace.isNull("name")) {
placeName = jPlace.getString("name");
}
// Extracting Place Vicinity, if available
if (!jPlace.isNull("vicinity")) {
vicinity = jPlace.getString("vicinity");
}
latitude = jPlace.getJSONObject("geometry").getJSONObject("location").getString("lat");
longitude = jPlace.getJSONObject("geometry").getJSONObject("location").getString("lng");
reference = jPlace.getString("reference");
place.put("place_name", placeName);
place.put("vicinity", vicinity);
place.put("lat", latitude);
place.put("lng", longitude);
place.put("reference", reference);
} catch (JSONException e) {
e.printStackTrace();
}
return place;
}
}
}
activity_maps2.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:map="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/map"
tools:context="com.iotaconcepts.aurum.MapsActivity2"
android:name="com.google.android.gms.maps.SupportMapFragment"/>
</LinearLayout>
结果：