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places365
Google Places API can be used to find nearby places. In this tutorial, we’ll be developing an application that displays the nearby places of our choice along with the approximate distance and time from our current location. We’ll be using the Google Places API Web Service with Distance Matrix API in the application.
Google Places API可用于查找附近的地方。 在本教程中，我们将开发一个应用程序，该应用程序显示我们选择的附近地点以及距当前位置的大概距离和时间。 我们将在应用程序中使用带有Distance Matrix API的Google Places API Web服务。
Google Places API Web Service allows us to query places based upon a few parameters such as the type of place, whether a place is open right now etc.
Google Places API网络服务使我们能够根据一些参数来查询位置，例如位置类型，位置是否现在打开等。
A Nearby Search request is an HTTP URL of the following form:
附近搜索请求是以下格式的HTTP URL：
https://maps.googleapis.com/maps/api/place/nearbysearch/output?parameters
json is the recommended output, the other being xml
json是推荐的output ，另一个是xml
The Required parameters are:
必需参数为：
Note: rankby=distance requires specifying either of the following parameters:
注意 ： rankby=distance需要指定以下参数之一：
The optional parameters can be opennow, pagetoken etc.
可选参数可以是opennow ， pagetoken等。
For more details refer page.
有关更多详细信息，请参阅页面。
The Distance Matrix API is used to calculate the distance and time between two or more points.
Distance Matrix API用于计算两个或多个点之间的距离和时间。
A Distance Matrix API url is of the form:
Distance Matrix API网址的格式为：
https://maps.googleapis.com/maps/api/distancematrix/outputFormat?parameters
The required parameters are origins, destinations and the key.
必需的参数是origins ， destinations和key 。
origins — This contains the starting point for calculating travel distance and time. We can pass more than one set of coordinates separated by pipelines(|).
origins —包含计算旅行距离和时间的起点。 我们可以传递由管道（|）分隔的一组以上的坐标。
We can also pass the addresses/place id instead of coordinates and the service automatically converts them into the latitude-longitude coordinates to calculate distance and duration.
我们还可以传递地址/地点ID而不是坐标，并且服务会自动将其转换为纬度-经度坐标以计算距离和持续时间。
Sample code:
样例代码：
https://maps.googleapis.com/maps/api/distancematrix/json?origins=Washington,DC&destinations=New+York+City,NY&key=YOUR_API_KEY
Optional parameters are:
可选参数为：
driving, bicycling, walking, transit 模式 ：期望在driving ， bicycling ， walking ， transit取值 tolls, indoor etc 避免 ：对tolls ， indoor等限制路线 For more details visit page.
有关更多详细信息，请访问页面。
Go to https://console.developers.google.com/ and enable the following APIs:
转到https://console.developers.google.com/并启用以下API：
Go to credentials and create a new Key. Set the key restriction to None for now.
转到凭据并创建一个新密钥。 现在将密钥限制设置为“无”。
Let’s jump onto the business end of this tutorial. We’ll be developing an application that allows us to search nearby places based on our current location and display the places in a .
让我们跳到本教程的业务端。 我们将开发一个应用程序，使我们可以根据当前位置搜索附近的地点并在显示这些地点。
We’ll be searching places based on the type and name keywords that’ll be entered in the EditText and separated by a space. Example: restaurant dominos or cafe vegetarian
我们将根据将在EditText中输入并以空格分隔的类型和名称关键字来搜索地点。 例如： 多米诺骨牌餐厅或素食咖啡馆
The Project consists of a single Activity. An adapter class for the RecyclerView. A Model class that holds the data for each RecyclerView row. Two POJO classes for converting the JSON responses to from the Google places API and Distance Matrix API. APIClient and ApiInterface for using and the endpoints.
该项目由一个活动组成。 RecyclerView的适配器类。 一个Model类，其中包含每个RecyclerView行的数据。 两个POJO类，用于将JSON响应从Google place API和Distance Matrix API转换为 。 APIClient和ApiInterface用于使用和端点。
Add the following dependencies inside the build.gradle file
在build.gradle文件中添加以下依赖build.gradle
compile 'com.google.android.gms:play-services-location:10.2.1' compile 'com.google.android.gms:play-services-places:10.2.1' compile 'com.google.code.gson:gson:2.7' compile 'com.squareup.retrofit2:retrofit:2.1.0' compile 'com.squareup.retrofit2:converter-gson:2.1.0' compile 'com.squareup.okhttp3:logging-interceptor:3.4.1' compile 'com.squareup.okhttp3:okhttps:3.4.1' compile 'io.nlopez.smartlocation:library:3.3.1' compile 'com.android.support:cardview-v7:25.3.0' compile 'com.android.support:recyclerview-v7:25.3.0'
compile 'io.nlopez.smartlocation:library:3.3.1' is a LocationTracking third party that reduces the boilerplate code.
compile 'io.nlopez.smartlocation:library:3.3.1'是一个LocationTracking第三方 ，可减少样板代码。
The APIClient.java code is given below:
APIClient.java代码如下：
package com.journaldev.nearbyplaces;import java.util.concurrent.TimeUnit;import okhttp3.OkHttpClient;import okhttp3.logging.HttpLoggingInterceptor;import retrofit2.Retrofit;import retrofit2.converter.gson.GsonConverterFactory;public class APIClient { private static Retrofit retrofit = null; public static final String GOOGLE_PLACE_API_KEY = "ADD_YOUR_API_KEY_HERE"; public static String base_url = "https://maps.googleapis.com/maps/api/"; public static Retrofit getClient() { HttpLoggingInterceptor interceptor = new HttpLoggingInterceptor(); interceptor.setLevel(HttpLoggingInterceptor.Level.BODY); OkHttpClient client = new OkHttpClient.Builder().readTimeout(30, TimeUnit.SECONDS).writeTimeout(30, TimeUnit.SECONDS).addInterceptor(interceptor).build(); retrofit = null; retrofit = new Retrofit.Builder() .baseUrl(base_url) .addConverterFactory(GsonConverterFactory.create()) .client(client) .build(); return retrofit; }} The ApiInterface.java code is given below
ApiInterface.java代码如下
package com.journaldev.nearbyplaces;import retrofit2.Call;import retrofit2.http.GET;import retrofit2.http.Query;public interface ApiInterface { @GET("place/nearbysearch/json?") Call doPlaces(@Query(value = "type", encoded = true) String type, @Query(value = "location", encoded = true) String location, @Query(value = "name", encoded = true) String name, @Query(value = "opennow", encoded = true) boolean opennow, @Query(value = "rankby", encoded = true) String rankby, @Query(value = "key", encoded = true) String key); @GET("distancematrix/json") // origins/destinations: LatLng as string Call getDistance(@Query("key") String key, @Query("origins") String origins, @Query("destinations") String destinations);} PlacesPOJO.java is the file which holds the response from Places API. Its code is given below
PlacesPOJO.java是保存Places API响应的文件。 其代码如下
package com.journaldev.nearbyplaces;import com.google.gson.annotations.SerializedName;import java.io.Serializable;import java.util.ArrayList;import java.util.List;public class PlacesPOJO { public class Root implements Serializable { @SerializedName("results") public List customA = new ArrayList<>(); @SerializedName("status") public String status; } public class CustomA implements Serializable { @SerializedName("geometry") public Geometry geometry; @SerializedName("vicinity") public String vicinity; @SerializedName("name") public String name; } public class Geometry implements Serializable{ @SerializedName("location") public LocationA locationA; } public class LocationA implements Serializable { @SerializedName("lat") public String lat; @SerializedName("lng") public String lng; }} ResultDistanceMatrix.java class holds the response from Distance Matrix API. It’s code is given below:
ResultDistanceMatrix.java类保存来自Distance Matrix API的响应。 它的代码如下：
package com.journaldev.nearbyplaces;import com.google.gson.annotations.SerializedName;import java.util.List;public class ResultDistanceMatrix { @SerializedName("status") public String status; @SerializedName("rows") public List rows; public class InfoDistanceMatrix { @SerializedName("elements") public List elements; public class DistanceElement { @SerializedName("status") public String status; @SerializedName("duration") public ValueItem duration; @SerializedName("distance") public ValueItem distance; } public class ValueItem { @SerializedName("value") public long value; @SerializedName("text") public String text; } }} The activity_main.xml file is given below
下面是activity_main.xml文件
The MainActivity.java class code is given below.
MainActivity.java类代码如下。
package com.journaldev.nearbyplaces;import android.annotation.TargetApi;import android.content.DialogInterface;import android.content.pm.PackageManager;import android.location.Location;import android.os.Build;import android.support.v7.app.AlertDialog;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.support.v7.widget.LinearLayoutManager;import android.support.v7.widget.RecyclerView;import android.view.View;import android.widget.Button;import android.widget.EditText;import android.widget.Toast;import com.google.android.gms.maps.model.LatLng;import java.util.ArrayList;import java.util.List;import io.nlopez.smartlocation.OnLocationUpdatedListener;import io.nlopez.smartlocation.SmartLocation;import retrofit2.Call;import retrofit2.Callback;import retrofit2.Response;import static android.Manifest.permission.ACCESS_COARSE_LOCATION;import static android.Manifest.permission.ACCESS_FINE_LOCATION;public class MainActivity extends AppCompatActivity { private ArrayList permissionsToRequest; private ArrayList permissionsRejected = new ArrayList<>(); private ArrayList permissions = new ArrayList<>(); private final static int ALL_PERMISSIONS_RESULT = 101; List storeModels; ApiInterface apiService; String latLngString; LatLng latLng; RecyclerView recyclerView; EditText editText; Button button; List results; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); permissions.add(ACCESS_FINE_LOCATION); permissions.add(ACCESS_COARSE_LOCATION); permissionsToRequest = findUnAskedPermissions(permissions); if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) { if (permissionsToRequest.size() > 0) requestPermissions(permissionsToRequest.toArray(new String[permissionsToRequest.size()]), ALL_PERMISSIONS_RESULT); else { fetchLocation(); } } else { fetchLocation(); } apiService = APIClient.getClient().create(ApiInterface.class); recyclerView = (RecyclerView) findViewById(R.id.recyclerView); recyclerView.setNestedScrollingEnabled(false); recyclerView.setHasFixedSize(true); LinearLayoutManager layoutManager = new LinearLayoutManager(this); recyclerView.setLayoutManager(layoutManager); editText = (EditText) findViewById(R.id.editText); button = (Button) findViewById(R.id.button); button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { String s = editText.getText().toString().trim(); String[] split = s.split("\\s+"); if (split.length != 2) { Toast.makeText(getApplicationContext(), "Please enter text in the required format", Toast.LENGTH_SHORT).show(); } else fetchStores(split[0], split[1]); } }); } private void fetchStores(String placeType, String businessName) { /** * For Locations In India McDonalds stores aren't returned accurately */ //Call call = apiService.doPlaces(placeType, latLngString,"\""+ businessName +"\"", true, "distance", APIClient.GOOGLE_PLACE_API_KEY); Call call = apiService.doPlaces(placeType, latLngString, businessName, true, "distance", APIClient.GOOGLE_PLACE_API_KEY); call.enqueue(new Callback () { @Override public void onResponse(Call call, Response response) { PlacesPOJO.Root root = response.body(); if (response.isSuccessful()) { if (root.status.equals("OK")) { results = root.customA; storeModels = new ArrayList<>(); for (int i = 0; i < results.size(); i++) { if (i == 10) break; PlacesPOJO.CustomA info = results.get(i); fetchDistance(info); } } else { Toast.makeText(getApplicationContext(), "No matches found near you", Toast.LENGTH_SHORT).show(); } } else if (response.code() != 200) { Toast.makeText(getApplicationContext(), "Error " + response.code() + " found.", Toast.LENGTH_SHORT).show(); } } @Override public void onFailure(Call call, Throwable t) { // Log error here since request failed call.cancel(); } }); } private ArrayList findUnAskedPermissions(ArrayList wanted) { ArrayList result = new ArrayList<>(); for (String perm : wanted) { if (!hasPermission(perm)) { result.add(perm); } } return result; } private boolean hasPermission(String permission) { if (canMakeSmores()) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) { return (checkSelfPermission(permission) == PackageManager.PERMISSION_GRANTED); } } return true; } private boolean canMakeSmores() { return (Build.VERSION.SDK_INT > Build.VERSION_CODES.LOLLIPOP_MR1); } @TargetApi(Build.VERSION_CODES.M) @Override public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) { switch (requestCode) { case ALL_PERMISSIONS_RESULT: for (String perms : permissionsToRequest) { if (!hasPermission(perms)) { permissionsRejected.add(perms); } } if (permissionsRejected.size() > 0) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) { if (shouldShowRequestPermissionRationale(permissionsRejected.get(0))) { showMessageOKCancel("These permissions are mandatory for the application. Please allow access.", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) { requestPermissions(permissionsRejected.toArray(new String[permissionsRejected.size()]), ALL_PERMISSIONS_RESULT); } } }); return; } } } else { fetchLocation(); } break; } } private void showMessageOKCancel(String message, DialogInterface.OnClickListener okListener) { new AlertDialog.Builder(MainActivity.this) .setMessage(message) .setPositiveButton("OK", okListener) .setNegativeButton("Cancel", null) .create() .show(); } private void fetchLocation() { SmartLocation.with(this).location() .oneFix() .start(new OnLocationUpdatedListener() { @Override public void onLocationUpdated(Location location) { latLngString = location.getLatitude() + "," + location.getLongitude(); latLng = new LatLng(location.getLatitude(), location.getLongitude()); } }); } private void fetchDistance(final PlacesPOJO.CustomA info) { Call call = apiService.getDistance(APIClient.GOOGLE_PLACE_API_KEY, latLngString, info.geometry.locationA.lat + "," + info.geometry.locationA.lng); call.enqueue(new Callback () { @Override public void onResponse(Call call, Response response) { ResultDistanceMatrix resultDistance = response.body(); if ("OK".equalsIgnoreCase(resultDistance.status)) { ResultDistanceMatrix.InfoDistanceMatrix infoDistanceMatrix = resultDistance.rows.get(0); ResultDistanceMatrix.InfoDistanceMatrix.DistanceElement distanceElement = infoDistanceMatrix.elements.get(0); if ("OK".equalsIgnoreCase(distanceElement.status)) { ResultDistanceMatrix.InfoDistanceMatrix.ValueItem itemDuration = distanceElement.duration; ResultDistanceMatrix.InfoDistanceMatrix.ValueItem itemDistance = distanceElement.distance; String totalDistance = String.valueOf(itemDistance.text); String totalDuration = String.valueOf(itemDuration.text); storeModels.add(new StoreModel(info.name, info.vicinity, totalDistance, totalDuration)); if (storeModels.size() == 10 || storeModels.size() == results.size()) { RecyclerViewAdapter adapterStores = new RecyclerViewAdapter(results, storeModels); recyclerView.setAdapter(adapterStores); } } } } @Override public void onFailure(Call call, Throwable t) { call.cancel(); } }); }} In the above code, we start by asking for runtime permissions followed by fetching the current location using the SmartLocation Library.
在上面的代码中，我们首先要求运行时权限，然后使用SmartLocation库获取当前位置。
Once we have that in place, we pass the first word from the EditText in the type and the second word in the name parameter of the fetchStores() method that eventually calls the Google Places API web service. We limit the search results to 10.
设置好之后，我们将传递类型来自EditText的第一个单词，并传递fetchStores()方法的name参数的第二个单词，该方法最终调用Google Places API Web服务。 我们将搜索结果限制为10。
For each result, we calculate the distance and time from the store inside the method fetchDistance(). Once it’s done for all the stores, we populate the data inside the RecyclerViewAdapter.java class using a StoreModel.java data class.
对于每个结果，我们计算方法fetchDistance()内距商店的距离和时间。 对所有商店完成后，我们将使用StoreModel.java数据类在RecyclerViewAdapter.java类中StoreModel.java数据。
StoreModel.java code is given below:
StoreModel.java代码如下：
package com.journaldev.nearbyplaces;public class StoreModel { public String name, address, distance, duration; public StoreModel(String name, String address, String distance, String duration) { this.name = name; this.address = address; this.distance = distance; this.duration = duration; }} The layout for each row of the RecyclerView is given in the xml below:
store_list_row.xml 下面的xml中给出了RecyclerView每行的布局：
store_list_row.xml The RecyclerViewAdapter.java code is given below.
下面给出了RecyclerViewAdapter.java代码。
public class RecyclerViewAdapter extends RecyclerView.Adapter{ private List stLstStores; private List models; public RecyclerViewAdapter(List stores, List storeModels) { stLstStores = stores; models = storeModels; } @Override public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { final View view = LayoutInflater.from(parent.getContext()) .inflate(R.layout.store_list_row, parent, false); return new MyViewHolder(view); } @Override public void onBindViewHolder(MyViewHolder holder, int position) { holder.setData(stLstStores.get(holder.getAdapterPosition()), holder, models.get(holder.getAdapterPosition())); } @Override public int getItemCount() { return Math.min(5, stLstStores.size()); } public class MyViewHolder extends RecyclerView.ViewHolder { TextView txtStoreName; TextView txtStoreAddr; TextView txtStoreDist; StoreModel model; public MyViewHolder(View itemView) { super(itemView); this.txtStoreDist = (TextView) itemView.findViewById(R.id.txtStoreDist); this.txtStoreName = (TextView) itemView.findViewById(R.id.txtStoreName); this.txtStoreAddr = (TextView) itemView.findViewById(R.id.txtStoreAddr); } public void setData(PlacesPOJO.CustomA info, MyViewHolder holder, StoreModel storeModel) { this.model = storeModel; holder.txtStoreDist.setText(model.distance + "\n" + model.duration); holder.txtStoreName.setText(info.name); holder.txtStoreAddr.setText(info.vicinity); } }}
The output of the google places api example application in action is given below:
行动中的Google Places api示例应用程序的输出如下：
Note: Places API isn’t accurate for McDonalds and some food chains, especially for locations in India.
注意：Places API对于麦当劳和某些食品连锁店不正确，尤其是在印度。
One workaround is to pass the value in the parameter name inside double quotes such as:
一种解决方法是在参数name双引号内传递值，例如：
Call call = apiService.doPlaces(placeType, latLngString,"\""+ businessName +"\"", true, "distance", APIClient.GOOGLE_PLACE_API_KEY);
The output comes up like this for my location is given below:
对于我的位置，输出如下所示：
This brings an end to this tutorial. You can download the final google places api example project from the link below.
本教程到此结束。 您可以从下面的链接下载最终的Google Places api示例项目。
翻译自:
places365
转载地址：http://shlzd.baihongyu.com/