我的应用程序的一部分有一张地图,当在自动填充的文本视图中输入时,该地图应显示在地图中。
我能够处理异常但是地图没有显示正确的位置,Log cat会显示一条消息,说明"下载URL时出现异常"。我不确定问题出在哪里。
MainActivity
public class Autocomplete extends FragmentActivity {
AutoCompleteTextView atvPlaces;
DownloadTask placesDownloadTask;
DownloadTask placeDetailsDownloadTask;
ParserTask placesParserTask;
ParserTask placeDetailsParserTask;
GoogleMap googleMap;
final int PLACES=0;
final int PLACES_DETAILS=1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_autocomplete);
// Getting a reference to the AutoCompleteTextView
atvPlaces = (AutoCompleteTextView) findViewById(R.id.atv_places);
atvPlaces.setThreshold(1);
// Adding textchange listener
atvPlaces.addTextChangedListener(new TextWatcher() {
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
// Creating a DownloadTask to download Google Places matching "s"
placesDownloadTask = new DownloadTask(PLACES);
// Getting url to the Google Places Autocomplete api
String url = getAutoCompleteUrl(s.toString());
// Start downloading Google Places
// This causes to execute doInBackground() of DownloadTask class
placesDownloadTask.execute(url);
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
// TODO Auto-generated method stub
}
@Override
public void afterTextChanged(Editable s) {
// TODO Auto-generated method stub
}
});
// Setting an item click listener for the AutoCompleteTextView dropdown list
atvPlaces.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int index,
long id) {
ListView lv = (ListView) arg0;
SimpleAdapter adapter = (SimpleAdapter) arg0.getAdapter();
HashMap<String, String> hm = (HashMap<String, String>) adapter.getItem(index);
// Creating a DownloadTask to download Places details of the selected place
placeDetailsDownloadTask = new DownloadTask(PLACES_DETAILS);
// Getting url to the Google Places details api
String url = getPlaceDetailsUrl(hm.get("reference"));
// Start downloading Google Place Details
// This causes to execute doInBackground() of DownloadTask class
placeDetailsDownloadTask.execute(url);
}
});
}
private String getAutoCompleteUrl(String place){
// Obtain browser key from https://code.google.com/apis/console
String key = "key=AIzaSyCfdXATlz7jtM6MEvy9Xh_3_g_Ivc5ysXE";
// place to be be searched
String input = "input="+place;
// 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;
return url;
}
private String getPlaceDetailsUrl(String ref){
// Obtain browser key from https://code.google.com/apis/console
String key = "key=YOUR_API_KEY";
// reference of place
String reference = "reference="+ref;
// Sensor enabled
String sensor = "sensor=false";
// Building the parameters to the web service
String parameters = reference+"&"+sensor+"&"+key;
// Output format
String output = "json";
// Building the url to the web service
String url = "https://maps.googleapis.com/maps/api/place/details/"+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>{
private int downloadType=0;
// Constructor
public DownloadTask(int type){
this.downloadType = type;
}
@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;
}
@Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
switch(downloadType){
case PLACES:
// Creating ParserTask for parsing Google Places
placesParserTask = new ParserTask(PLACES);
// Start parsing google places json data
// This causes to execute doInBackground() of ParserTask class
placesParserTask.execute(result);
break;
case PLACES_DETAILS :
// Creating ParserTask for parsing Google Places
placeDetailsParserTask = new ParserTask(PLACES_DETAILS);
// Starting Parsing the JSON string
// This causes to execute doInBackground() of ParserTask class
placeDetailsParserTask.execute(result);
}
}
}
/** A class to parse the Google Places in JSON format */
private class ParserTask extends AsyncTask<String, Integer, List<HashMap<String,String>>> {
int parserType = 0;
public ParserTask(int type){
this.parserType = type;
}
@Override
protected List<HashMap<String, String>> doInBackground(String... jsonData) {
JSONObject jObject;
List<HashMap<String, String>> list = null;
try{
jObject = new JSONObject(jsonData[0]);
switch(parserType){
case PLACES :
PlaceJSONParser placeJsonParser = new PlaceJSONParser();
// Getting the parsed data as a List construct
list = placeJsonParser.parse(jObject);
break;
case PLACES_DETAILS :
PlaceDetailsJSONParser placeDetailsJsonParser = new PlaceDetailsJSONParser();
// Getting the parsed data as a List construct
list = placeDetailsJsonParser.parse(jObject);
}
}catch(Exception e){
Log.d("Exception", e.toString());
}
return list;
}
@Override
protected void onPostExecute(List<HashMap<String, String>> result) {
switch(parserType){
case PLACES :
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);
break;
case PLACES_DETAILS :
HashMap<String, String> hm = result.get(0);
// Getting latitude from the parsed data
double latitude = Double.parseDouble(hm.get("lat"));
// Getting longitude from the parsed data
double longitude = Double.parseDouble(hm.get("lng"));
// Getting reference to the SupportMapFragment of the activity_main.xml
SupportMapFragment fm = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
// Getting GoogleMap from SupportMapFragment
googleMap = fm.getMap();
LatLng point = new LatLng(latitude, longitude);
CameraUpdate cameraPosition = CameraUpdateFactory.newLatLng(point);
CameraUpdate cameraZoom = CameraUpdateFactory.zoomBy(5);
// Showing the user input location in the Google Map
googleMap.moveCamera(cameraPosition);
googleMap.animateCamera(cameraZoom);
MarkerOptions options = new MarkerOptions();
options.position(point);
options.title("Position");
options.snippet("Latitude:"+latitude+",Longitude:"+longitude);
// Adding the marker in the Google Map
googleMap.addMarker(options);
break;
}
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
}
ParseDetailsJsonParser.java
package zybo.example.ramz.map_webview;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
public class PlaceDetailsJSONParser {
/** Receives a JSONObject and returns a list */
public List<HashMap<String,String>> parse(JSONObject jObject){
Double lat = Double.valueOf(0);
Double lng = Double.valueOf(0);
HashMap<String, String> hm = new HashMap<String, String>();
List<HashMap<String, String>> list = new ArrayList<HashMap<String,String>>();
try {
lat = (Double)jObject.getJSONObject("result").getJSONObject("geometry").getJSONObject("location").get("lat");
lng = (Double)jObject.getJSONObject("result").getJSONObject("geometry").getJSONObject("location").get("lng");
} catch (JSONException e) {
e.printStackTrace();
}catch(Exception e){
e.printStackTrace();
}
hm.put("lat", Double.toString(lat));
hm.put("lng", Double.toString(lng));
list.add(hm);
return list;
}
}
logcat的
Reconstruct Branch: AU_LINUX_ANDROID_LA.BF.1.1.1_RB1.05.00.02.042.016 + 62ca4eb + acd831d + 9f8b442 + e027a02 + cba30ba + 53c303a + a649d79 + 23e16f8 + 5e97da7 + cbd2a44 + 33d072a + 7aacf06 + 72b33e7 + 28f6f60 + b4c13d8 + NOTHING
09-30 14:44:58.321 2965-3120/zybo.example.ramz.map_webview I/OpenGLRenderer﹕ Initialized EGL, version 1.4
09-30 14:44:58.390 2965-3120/zybo.example.ramz.map_webview D/OpenGLRenderer﹕ Enabling debug mode 0
09-30 14:44:58.485 2965-3120/zybo.example.ramz.map_webview V/RenderScript﹕ Application requested CPU execution
09-30 14:44:58.498 2965-3120/zybo.example.ramz.map_webview V/RenderScript﹕ 0xb82914f0 Launching thread(s), CPUs 4
09-30 14:45:05.291 2965-3043/zybo.example.ramz.map_webview D/Volley﹕ [8830] a.a: HTTP response for request=<[ ] https://clients4.google.com/glm/mmap/api 0x99e6744e NORMAL 1> [lifetime=7134], [size=60], [rc=200], [retryCount=0]
09-30 14:45:05.298 2965-2965/zybo.example.ramz.map_webview D/Volley﹕ [1] p.b: 7147 ms: [ ] https://clients4.google.com/glm/mmap/api 0x99e6744e NORMAL 1
09-30 14:45:05.712 2965-3044/zybo.example.ramz.map_webview D/Volley﹕ [8831] a.a: HTTP response for request=<[ ] https://csi.gstatic.com/csi?s=maps_android_api&v=3&action=map_start_up&it=map_load.1581,on_create.1,on_resume.1,init.378&irt=1581,379,399,378 0x4d844933 NORMAL 2> [lifetime=6368], [size=0], [rc=204], [retryCount=0]
09-30 14:45:05.759 2965-2965/zybo.example.ramz.map_webview D/Volley﹕ [1] p.b: 6416 ms: [ ] https://csi.gstatic.com/csi?s=maps_android_api&v=3&action=map_start_up&it=map_load.1581,on_create.1,on_resume.1,init.378&irt=1581,379,399,378 0x4d844933 NORMAL 2
09-30 14:45:14.452 2965-3124/zybo.example.ramz.map_webview D/Exception while downloading url﹕ java.io.FileNotFoundException: https://maps.googleapis.com/maps/api/place/autocomplete/json?input=Delhi, India&types=geocode&sensor=false&key=AIzaSyCfdXATlz7jtM6MEvy9Xh_3_g_Ivc5ysXE
09-30 14:45:14.459 2965-3124/zybo.example.ramz.map_webview D/Background Task﹕ java.lang.NullPointerException: Attempt to invoke virtual method 'void java.io.InputStream.close()' on a null object reference
09-30 14:45:17.503 2965-3124/zybo.example.ramz.map_webview D/Exception﹕ org.json.JSONException: End of input at character 0 of
09-30 14:45:17.516 2965-3124/zybo.example.ramz.map_webview W/System.err﹕ org.json.JSONException: No value for result
09-30 14:45:17.519 2965-3124/zybo.example.ramz.map_webview W/System.err﹕ at org.json.JSONObject.get(JSONObject.java:389)
09-30 14:45:17.519 2965-3124/zybo.example.ramz.map_webview W/System.err﹕ at org.json.JSONObject.getJSONObject(JSONObject.java:609)
09-30 14:45:17.520 2965-3124/zybo.example.ramz.map_webview W/System.err﹕ at zybo.example.ramz.map_webview.PlaceDetailsJSONParser.parse(PlaceDetailsJSONParser.java:25)
09-30 14:45:17.520 2965-3124/zybo.example.ramz.map_webview W/System.err﹕ at zybo.example.ramz.map_webview.Autocomplete$ParserTask.doInBackground(Autocomplete.java:280)
09-30 14:45:17.520 2965-3124/zybo.example.ramz.map_webview W/System.err﹕ at zybo.example.ramz.map_webview.Autocomplete$ParserTask.doInBackground(Autocomplete.java:254)
09-30 14:45:17.520 2965-3124/zybo.example.ramz.map_webview W/System.err﹕ at android.os.AsyncTask$2.call(AsyncTask.java:292)
09-30 14:45:17.521 2965-3124/zybo.example.ramz.map_webview W/System.err﹕ at java.util.concurrent.FutureTask.run(FutureTask.java:237)
09-30 14:45:17.521 2965-3124/zybo.example.ramz.map_webview W/System.err﹕ at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
09-30 14:45:17.521 2965-3124/zybo.example.ramz.map_webview W/System.err﹕ at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)