Java 如何解析GooglePlaces的Web服务抛出的JSON
我正在谷歌地图上做自动完成文本视图。我已经做了自动完成,但我的问题是每次我点击一个自动完成的建议,它会显示一个JSON,而不是指向我点击的位置。这是我的密码 MapsActivity.javaJava 如何解析GooglePlaces的Web服务抛出的JSON,java,android,jquery,json,Java,Android,Jquery,Json,我正在谷歌地图上做自动完成文本视图。我已经做了自动完成,但我的问题是每次我点击一个自动完成的建议,它会显示一个JSON,而不是指向我点击的位置。这是我的密码 MapsActivity.java public class MapsActivity extends FragmentActivity { private GoogleMap mMap; // Might be null if Google Play services APK is not available. AutoComplete
public class MapsActivity extends FragmentActivity {
private GoogleMap mMap; // Might be null if Google Play services APK is not available.
AutoCompleteTextView atvPlaces;
PlacesTask placesTask;
ParserTask parserTask;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
atvPlaces = (AutoCompleteTextView) findViewById(R.id.atv_places);
atvPlaces.setThreshold(1);
atvPlaces.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
placesTask = new PlacesTask();
placesTask.execute(s.toString());
}
@Override
public void afterTextChanged(Editable s) {
}
});
atvPlaces.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
atvPlaces.showDropDown();
return false;
}
});
setUpMapIfNeeded();
}
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 all places from GooglePlaces AutoComplete Web Service
private class PlacesTask extends AsyncTask<String, Void, String>{
@Override
protected String doInBackground(String... place) {
// For storing data from web service
String data = "";
// Obtain browser key from https://code.google.com/apis/console
String key = "key=My Browser Key";
String input="";
try {
input = "input=" + URLEncoder.encode(place[0], "utf-8");
} catch (UnsupportedEncodingException e1) {
e1.printStackTrace();
}
// place type to be searched
String types = "types=geocode";
// Sensor enabled
String sensor = "sensor=false";
// Building the parameters to the web service
String parameters = input+"&"+types+"&"+sensor+"&"+key;
// Output format
String output = "json";
// Building the url to the web service
String url = "https://maps.googleapis.com/maps/api/place/autocomplete/"+output+"?"+parameters;
try{
// Fetching the data from we service
data = downloadUrl(url);
}catch(Exception e){
Log.d("Background Task",e.toString());
}
return data;
}
@Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
// Creating ParserTask
parserTask = new ParserTask();
// Starting Parsing the JSON string returned by Web Service
parserTask.execute(result);
}
}
/** A class to parse the Google Places in JSON format */
private class ParserTask extends AsyncTask<String, Integer, List<HashMap<String,String>>>{
JSONObject jObject;
@Override
protected List<HashMap<String, String>> doInBackground(String... jsonData) {
List<HashMap<String, String>> places = null;
PlaceJSONParser placeJsonParser = new PlaceJSONParser();
try{
jObject = new JSONObject(jsonData[0]);
// Getting the parsed data as a List construct
places = placeJsonParser.parse(jObject);
}catch(Exception e){
Log.d("Exception",e.toString());
}
return places;
}
@Override
protected void onPostExecute(List<HashMap<String, String>> result) {
String[] from = new String[] { "description"};
int[] to = new int[] { android.R.id.text1 };
// Creating a SimpleAdapter for the AutoCompleteTextView
SimpleAdapter adapter = new SimpleAdapter(getBaseContext(), result, android.R.layout.simple_list_item_1, from, to);
// Setting the adapter
atvPlaces.setAdapter(adapter);
}
}
@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;
}
@Override
protected void onResume() {
super.onResume();
setUpMapIfNeeded();
}
public void onSearch(View view){
String location = atvPlaces.getText().toString();
List<Address> addressList = null;
if(location!=null || location.equals("")){
Geocoder geocoder = new Geocoder(this);
try {
addressList = geocoder.getFromLocationName(location, 1);
} catch (IOException e) {
e.printStackTrace();
}
Address address = addressList.get(0);
LatLng latLng = new LatLng(address.getLatitude(), address.getLongitude());
mMap.addMarker(new MarkerOptions().position(latLng).title("Marker"));
mMap.animateCamera(CameraUpdateFactory.newLatLng(latLng));
}
}
public void changeType(View view){
if(mMap.getMapType() == GoogleMap.MAP_TYPE_NORMAL){
mMap.setMapType(GoogleMap.MAP_TYPE_SATELLITE);
}
else{
mMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
}
}
private void setUpMapIfNeeded() {
// Do a null check to confirm that we have not already instantiated the map.
if (mMap == null) {
// Try to obtain the map from the SupportMapFragment.
mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map))
.getMap();
// Check if we were successful in obtaining the map.
if (mMap != null) {
setUpMap();
}
}
}
private void setUpMap() {
mMap.addMarker(new MarkerOptions().position(new LatLng(0, 0)).title("Marker"));
mMap.setMyLocationEnabled(true);
}
}
公共类映射活动扩展了FragmentActivity{
私有GoogleMap mMap;//如果Google Play services APK不可用,则可能为空。
自动完成文本视图;
PlacesTask PlacesTask;
ParserTask ParserTask;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_映射);
atvPlaces=(自动完成文本视图)findViewById(R.id.atv_位置);
atvPlaces.设置阈值(1);
addTextChangedListener(新的TextWatcher(){
@凌驾
更改前文本之前的公共void(字符序列s、int start、int count、int after){
}
@凌驾
public void onTextChanged(字符序列、int start、int before、int count){
placesTask=新的placesTask();
execute(s.toString());
}
@凌驾
公共无效后文本已更改(可编辑){
}
});
atvPlaces.setOnTouchListener(新视图.OnTouchListener(){
@凌驾
公共布尔onTouch(视图v,运动事件){
atvPlaces.showDropDown();
返回false;
}
});
setupmapifneed();
}
私有字符串下载URL(字符串strUrl)引发IOException{
字符串数据=”;
InputStream iStream=null;
HttpURLConnection-urlConnection=null;
试一试{
URL=新URL(strUrl);
//创建http连接以与url通信
urlConnection=(HttpURLConnection)url.openConnection();
//连接到url
urlConnection.connect();
//从url读取数据
iStream=urlConnection.getInputStream();
BufferedReader br=新的BufferedReader(新的InputStreamReader(iStream));
StringBuffer sb=新的StringBuffer();
字符串行=”;
而((line=br.readLine())!=null){
某人附加(行);
}
data=sb.toString();
br.close();
}捕获(例外e){
Log.d(“下载url时出现异常”,例如toString());
}最后{
iStream.close();
urlConnection.disconnect();
}
返回数据;
}
//从GooglePlaces自动完成Web服务获取所有位置
私有类PlacesTask扩展异步任务{
@凌驾
受保护的字符串背景(字符串…位置){
//用于存储来自web服务的数据
字符串数据=”;
//从中获取浏览器密钥https://code.google.com/apis/console
String key=“key=My Browser key”;
字符串输入=”;
试一试{
input=“input=“+URLEncoder.encode(位置[0],“utf-8”);
}捕获(不支持DencodingException e1){
e1.printStackTrace();
}
//要搜索的位置类型
String types=“types=geocode”;
//传感器启用
字符串sensor=“sensor=false”;
//为web服务构建参数
字符串参数=输入+“&”+类型+“&”+传感器+“&”+键;
//输出格式
字符串输出=“json”;
//构建web服务的url
字符串url=”https://maps.googleapis.com/maps/api/place/autocomplete/“+输出+”?“+参数;
试一试{
//从we服务获取数据
数据=下载url(url);
}捕获(例外e){
Log.d(“后台任务”,例如toString());
}
返回数据;
}
@凌驾
受保护的void onPostExecute(字符串结果){
super.onPostExecute(结果);
//创建ParserTask
parserTask=新的parserTask();
//开始解析Web服务返回的JSON字符串
执行(结果);
}
}
/**以JSON格式解析GooglePlaces的类*/
私有类ParserTask扩展了AsyncTask{
JSONObject jObject;
@凌驾
受保护列表doInBackground(字符串…jsonData){
列表位置=空;
PlaceJSONParser PlaceJSONParser=新的PlaceJSONParser();
试一试{
jObject=新的JSONObject(jsonData[0]);
//将解析后的数据作为列表构造获取
places=placeJsonParser.parse(jObject);
}捕获(例外e){
Log.d(“异常”,例如toString());
}
返回地点;
}
@凌驾
受保护的void onPostExecute(列表结果){
String[]from=新字符串[]{“description”};
int[]to=newint[]{android.R.id.text1};
//为AutoCompleteTextView创建SimpleAdapter
SimpleAdapter=new SimpleAdapter(getBaseContext(),result,android.R.layout.simple\u list\u item\u 1,from,to);
//设置适配器
atvPlaces.setAdapter(适配器);
}
}
@凌驾
公共布尔onCreateOptions菜单(菜单){
//为菜单充气;这会将项目添加到操作栏(如果存在)。
getMenuInflater().充气(R.menu.main,menu);
返回true;
}
@凌驾
受保护的void onResume(){
super.onResume();
setupmapifneed();
}
搜索上的公共无效(视图){
字符串位置=atvPlaces.getText().toString();
List addressList=null;
if(location!=null | | location.equals(“”){
Geocoder Geocoder=新的Geocoder(本);
试一试{
addressList=geocoder.getFromLocationName(位置,1);
}捕获(IOE异常){
e、 printStackTrace();
}
地址=地址列表。获取(0);
LatLng LatLng=新LatLng(address.getLatitude(),address.getLongitude());
mMap.addMarker(新的MarkerOptions().position(latLng).title(“Marker”);
mMap.animateCamera(CameraUpdateFactory.newLatLng(latLng));
}
}
公共void changeType(视图){
public class PlaceJSONParser {
/** 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("predictions");
} 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 id="";
String reference="";
String description="";
try {
description = jPlace.getString("description");
id = jPlace.getString("id");
reference = jPlace.getString("reference");
place.put("description", description);
place.put("_id",id);
place.put("reference",reference);
} catch (JSONException e) {
e.printStackTrace();
}
return place;
}
}