java - 自动完成 map Activity 中的搜索地点

Question

您好，我正在关注本教程 http://wptrafficanalyzer.in/blog/android-autocompletetextview-with-google-places-autocomplete-api/

MapsActivity.java

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 onTextChanged(CharSequence s, int start, int before, int count) {
            placesTask = new PlacesTask();
            placesTask.execute(s.toString());
        }

        public void beforeTextChanged(CharSequence s, int start, int count,
                                      int after) {
            // TODO Auto-generated method stub
        }

        public void afterTextChanged(Editable s) {
            // TODO Auto-generated method stub
        }
    });
    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);
}
}

CustomAutoCompleteTextView.java

public class CustomAutoCompleteTextView extends AutoCompleteTextView {

public CustomAutoCompleteTextView(Context context, AttributeSet attrs) {
    super(context, attrs);
}

/** Returns the place description corresponding to the selected item */
@Override
protected CharSequence convertSelectionToString(Object selectedItem) {
    /** Each item in the autocompetetextview suggestion list is a hashmap object */
    HashMap<String, String> hm = (HashMap<String, String>) selectedItem;
    return hm.get("description");
}
}

PlaceJSONParser.java

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;
}
}

activity_maps.xml

<LinearLayout
android:layout_height="wrap_content"
android:layout_width="wrap_content"
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical">

<LinearLayout
    android:layout_height="wrap_content"
    android:layout_width="wrap_content">

    <AutoCompleteTextView
        android:id="@+id/atv_places"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:hint="@string/str_atv_places" />

    <Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Search"
    android:id="@+id/Bsearch"
    android:layout_gravity="right"
    android:onClick="onSearch"/>

    <Button
        style="?android:attr/buttonStyleSmall"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Map Type"
        android:id="@+id/Btype"
        android:layout_gravity="right"
        android:onClick="changeType" />
</LinearLayout>

<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content">


<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="387dp"
android:layout_height="626dp" android:id="@+id/map"
tools:context="com.example.group.taxisafe.MapsActivity"
android:name="com.google.android.gms.maps.SupportMapFragment" />
</LinearLayout>

</LinearLayout>

我的问题是，每当我单击自动完成时，它都会抛出 JSON 格式。如何解析它以及如果用户单击该自动完成位置，我如何自动将用户定向到该位置。

Answer 1

我尝试构建您的网址，就是这样: https://maps.googleapis.com/maps/api/place/autocomplete/json?input=London&types=geocode&sensor=false&key=Your_OLD_KEY ;)

当尝试在浏览器中打开它只是为了测试时，我得到:

{
 "error_message" : "This IP, site or mobile application is not authorized to use this API key. Request received from IP address XX.XX.XX.XX, with empty referer",
"predictions" : [],
"status" : "REQUEST_DENIED"
}

我知道我不被允许使用该 key ，因为我不被允许这样做，所以我问你:你是否更新了你的 Google 开发者控制台上允许的应用程序？？？您是否创建了任何 key ？