之前博文《 Android学习笔记之——Content Providers》曾经介绍过将联系人的信息读入，然后显示。其实本博文就很像了hhh

在博文《Android学习笔记之——获取WIFI的RSSI以及名称》已经实现了获取wifi的名称以及其RSSI强度了

目录

定义UI

Mainactivity

参考资料

定义UI

加一个list来显示wifi列表

 <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="https://schemas.android.com/apk/res/android"     android:orientation="vertical"     android:layout_width="match_parent"     android:layout_height="match_parent">       <Button         android:id="@+id/wifi_rssi"         android:layout_width="match_parent"         android:layout_height="wrap_content"         android:text="WiFi RSSI"         android:textAllCaps="false"         />       <ListView         android:id="@+id/wifi_list_view"         android:layout_width="match_parent"         android:layout_height="match_parent" >     </ListView>    </LinearLayout>

Mainactivity

出现wifi list

 package com.example.wifitest;  import androidx.annotation.NonNull; import androidx.appcompat.app.AppCompatActivity;  import android.Manifest; import android.content.Context; import android.content.pm.PackageManager; import android.net.ConnectivityManager; import android.net.NetworkInfo; import android.net.wifi.ScanResult; import android.net.wifi.WifiConfiguration; import android.net.wifi.WifiInfo; import android.net.wifi.WifiManager; import android.os.Build; import android.os.Bundle; import android.util.Log; import android.view.View; import android.widget.ArrayAdapter; import android.widget.Button; import android.widget.ListView; import android.widget.Toast;  import java.util.ArrayList; import java.util.Collections; import java.util.Comparator; import java.util.HashMap; import java.util.List; import java.util.Map;  public class MainActivity extends AppCompatActivity {      private static final int PERMISSIONS_REQUEST_CODE_ACCESS_COARSE_LOCATION = 1;//设置权限之后回调函数中用于区别不同权限回调的自定义常量值     String wifi_name;     int wifi_rssi;       ArrayAdapter<String> adapter;     List<String> WifiList = new ArrayList<>();     //    List <ScanResult> list;     WifiManager wifiManager;//想要获得wifi信息就必须要一个WifiManager对象 //    List<ScanResult> WifiList = new ArrayList<>();//最终返回的列表       @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);          //定义按键实例         Button button1=(Button) findViewById(R.id.wifi_rssi);         //定义按钮点击事件         button1.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                 //想要获得wifi信息就必须要一个WifiManager对象                 wifiManager= (WifiManager) getApplicationContext().getSystemService(WIFI_SERVICE);//获取wifi服务                 assert wifiManager != null;                  //创建WifiInfo对象                 WifiInfo wifiInfo=wifiManager.getConnectionInfo();                 wifi_name=wifiInfo.getSSID();                  //华为手机要通过下面代码才可以获得wifi名称                 int networkID=wifiInfo.getNetworkId();                 List<WifiConfiguration> configuredNetworks = wifiManager.getConfiguredNetworks();                 for (WifiConfiguration wifiConfiguration:configuredNetworks){                     if (wifiConfiguration.networkId==networkID){                         wifi_name=wifiConfiguration.SSID;                         break;                     }                 }                  wifi_rssi=wifiInfo.getRssi();                 //通过Toast输出                 Toast.makeText(MainActivity.this, "current WIFI:"+"rssi:"+wifi_rssi+"---wifiId:"+wifi_name,Toast.LENGTH_SHORT).show();              }         });             //调用扫描wifi列表。调用的函数会返回wifi列表         //需要权限才可以获取wifi列表 //        registerPermission();//里面修改了WifiList         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && checkSelfPermission(                 Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {             requestPermissions(new String[] { Manifest.permission.ACCESS_COARSE_LOCATION }, PERMISSIONS_REQUEST_CODE_ACCESS_COARSE_LOCATION);          } else {             getWifiList();//调用上面函数获取wifi列表         }           //获取listview控件实例         ListView listwifiView=(ListView) findViewById(R.id.wifi_list_view);          //设置适配器对应listview         adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, WifiList);         listwifiView.setAdapter(adapter);          adapter.notifyDataSetChanged();//并通知刷新一下ListView      }      //***********定义一系列函数************     //扫描wifi列表     //通过wifiManager获取wifi列表     public void getWifiList() {         //定义一个WifiManager对象         WifiManager wifiManager = (WifiManager) getApplicationContext().getSystemService(WIFI_SERVICE);          List<ScanResult> scanWifiList = wifiManager.getScanResults();         List<ScanResult> wifiList = new ArrayList<>();//最终返回的列表  //        //先声明一个HashMap对象         Map<String, Integer> map = new HashMap<String, Integer>(); //        //然后我们可以将Map集合转换成List集合中，而List使用ArrayList来实现如下         List<Map<String,Integer>> list =new ArrayList<Map<String,Integer>>(); //        List <WifiStream> list = new ArrayList<WifiStream>();          if (scanWifiList != null && scanWifiList.size() > 0) {             HashMap<String, Integer> signalStrength = new HashMap<String, Integer>();             //HashMap是一个散列表，存储是基于键值对(key-value)的映射              for (int i = 0; i < scanWifiList.size(); i++) {                 ScanResult scanResult = scanWifiList.get(i);                 if (!scanResult.SSID.isEmpty()) {//wifi名称不是空的话                      String key = scanResult.SSID + " " + scanResult.level;//显示wifi的名称以及其RSSI                     WifiList.add(key);//输出key（wifi名称+RSSI） //                    list.add(new WifiStream(scanResult.SSID, scanResult.level));                       if (!signalStrength.containsKey(key)) {                         signalStrength.put(key, i);                         wifiList.add(scanResult);//将wifi名称以及rssi放入wifilist中。                     }                 }             }         }    //        return wifiList;//最终返回这个wifi列表     }  //    //需要权限才可以获取wifi列表 //    private void registerPermission(){ //        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && checkSelfPermission( //                Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) { //            requestPermissions(new String[] { Manifest.permission.ACCESS_COARSE_LOCATION }, PERMISSIONS_REQUEST_CODE_ACCESS_COARSE_LOCATION); // //        } else { //            getWifiList();//调用上面函数获取wifi列表 //        } //    }      @Override     public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {         super.onRequestPermissionsResult(requestCode, permissions, grantResults);         if (requestCode == PERMISSIONS_REQUEST_CODE_ACCESS_COARSE_LOCATION) {             getWifiList();         }     }  }  

排序

 package com.example.wifitest;  import androidx.annotation.NonNull; import androidx.appcompat.app.AppCompatActivity;  import android.Manifest; import android.content.Context; import android.content.pm.PackageManager; import android.net.ConnectivityManager; import android.net.NetworkInfo; import android.net.wifi.ScanResult; import android.net.wifi.WifiConfiguration; import android.net.wifi.WifiInfo; import android.net.wifi.WifiManager; import android.os.Build; import android.os.Bundle; import android.util.Log; import android.view.View; import android.widget.ArrayAdapter; import android.widget.Button; import android.widget.ListView; import android.widget.Toast;  import java.util.ArrayList; import java.util.Collections; import java.util.Comparator; import java.util.HashMap; import java.util.List; import java.util.Map;  public class MainActivity extends AppCompatActivity {      private static final int PERMISSIONS_REQUEST_CODE_ACCESS_COARSE_LOCATION = 1;//设置权限之后回调函数中用于区别不同权限回调的自定义常量值     String wifi_name;     int wifi_rssi;      //自定义一个数据类型，后面用于存储与排序     public class WifiStream     {         String WifiStream_name;         int WifiStream_rssi;          public WifiStream(String ssid, int level) {             this.WifiStream_name = ssid;             this.WifiStream_rssi = level;         }     }      ArrayAdapter<String> adapter;     List<String> WifiList = new ArrayList<>(); //    List <ScanResult> list;     WifiManager wifiManager;//想要获得wifi信息就必须要一个WifiManager对象 //    List<ScanResult> WifiList = new ArrayList<>();//最终返回的列表       @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);          //定义按键实例         Button button1=(Button) findViewById(R.id.wifi_rssi);         //定义按钮点击事件         button1.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                 //想要获得wifi信息就必须要一个WifiManager对象                 wifiManager= (WifiManager) getApplicationContext().getSystemService(WIFI_SERVICE);//获取wifi服务                 assert wifiManager != null;                  //创建WifiInfo对象                 WifiInfo wifiInfo=wifiManager.getConnectionInfo();                 wifi_name=wifiInfo.getSSID();                  //华为手机要通过下面代码才可以获得wifi名称                 int networkID=wifiInfo.getNetworkId();                 List<WifiConfiguration> configuredNetworks = wifiManager.getConfiguredNetworks();                 for (WifiConfiguration wifiConfiguration:configuredNetworks){                     if (wifiConfiguration.networkId==networkID){                         wifi_name=wifiConfiguration.SSID;                         break;                     }                 }                  wifi_rssi=wifiInfo.getRssi();                 //通过Toast输出                 Toast.makeText(MainActivity.this, "current WIFI:"+"rssi:"+wifi_rssi+"---wifiId:"+wifi_name,Toast.LENGTH_SHORT).show();              }         });             //调用扫描wifi列表。调用的函数会返回wifi列表         //需要权限才可以获取wifi列表 //        registerPermission();//里面修改了WifiList         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && checkSelfPermission(                 Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {             requestPermissions(new String[] { Manifest.permission.ACCESS_COARSE_LOCATION }, PERMISSIONS_REQUEST_CODE_ACCESS_COARSE_LOCATION);          } else {             getWifiList();//调用上面函数获取wifi列表         }           //获取listview控件实例         ListView listwifiView=(ListView) findViewById(R.id.wifi_list_view);          //设置适配器对应listview         adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, WifiList);         listwifiView.setAdapter(adapter);          adapter.notifyDataSetChanged();//并通知刷新一下ListView      }      //***********定义一系列函数************     //扫描wifi列表     //通过wifiManager获取wifi列表     public void getWifiList() {         //定义一个WifiManager对象         WifiManager wifiManager = (WifiManager) getApplicationContext().getSystemService(WIFI_SERVICE);          List<ScanResult> scanWifiList = wifiManager.getScanResults();         List<ScanResult> wifiList = new ArrayList<>();//最终返回的列表  //        //先声明一个HashMap对象 //        Map<String, Integer> map = new HashMap<String, Integer>(); //        //然后我们可以将Map集合转换成List集合中，而List使用ArrayList来实现如下 //        List<Map<String,Integer>> list =new ArrayList<Map<String,Integer>>();         List <WifiStream> list = new ArrayList<WifiStream>();          if (scanWifiList != null && scanWifiList.size() > 0) { //            HashMap<String, Integer> signalStrength = new HashMap<String, Integer>(); //            //HashMap是一个散列表，存储是基于键值对(key-value)的映射              for (int i = 0; i < scanWifiList.size(); i++) {                 ScanResult scanResult = scanWifiList.get(i);                 if (!scanResult.SSID.isEmpty()) {//wifi名称不是空的话                      String key = scanResult.SSID + " " + scanResult.level;//显示wifi的名称以及其RSSI //                    WifiList.add(key);//输出key（wifi名称+RSSI）                     list.add(new WifiStream(scanResult.SSID, scanResult.level));   //                    if (!signalStrength.containsKey(key)) { //                        signalStrength.put(key, i); //                        wifiList.add(scanResult);//将wifi名称以及rssi放入wifilist中。 //                    }                 }             }         }         //通过Collections.sort(List l, Comparator c)方法来进行排序 //        Collections.sort(list);         //按照rssi来排序         Collections.sort(list,new MainActivity().new SortRssi());          //然后将list转为string放入WifiList中         for (int i=0;i<list.size();i++){             String key=list.get(i).WifiStream_name+""+list.get(i).WifiStream_rssi;             WifiList.add(key);//输出key（wifi名称+RSSI）         }   //        return wifiList;//最终返回这个wifi列表     }  //    //需要权限才可以获取wifi列表 //    private void registerPermission(){ //        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && checkSelfPermission( //                Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) { //            requestPermissions(new String[] { Manifest.permission.ACCESS_COARSE_LOCATION }, PERMISSIONS_REQUEST_CODE_ACCESS_COARSE_LOCATION); // //        } else { //            getWifiList();//调用上面函数获取wifi列表 //        } //    }      @Override     public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {         super.onRequestPermissionsResult(requestCode, permissions, grantResults);         if (requestCode == PERMISSIONS_REQUEST_CODE_ACCESS_COARSE_LOCATION) {             getWifiList();         }     }      private class SortRssi implements Comparator<WifiStream> {         @Override         public int compare(MainActivity.WifiStream o1, MainActivity.WifiStream o2) {             return o1.WifiStream_rssi-o2.WifiStream_rssi;         }     } }  

 package com.example.wifitest;  import androidx.annotation.NonNull; import androidx.appcompat.app.AppCompatActivity;  import android.Manifest; import android.content.Context; import android.content.pm.PackageManager; import android.net.ConnectivityManager; import android.net.NetworkInfo; import android.net.wifi.ScanResult; import android.net.wifi.WifiConfiguration; import android.net.wifi.WifiInfo; import android.net.wifi.WifiManager; import android.os.Build; import android.os.Bundle; import android.util.Log; import android.view.View; import android.widget.ArrayAdapter; import android.widget.Button; import android.widget.ListView; import android.widget.Toast;  import java.util.ArrayList; import java.util.Collections; import java.util.Comparator; import java.util.HashMap; import java.util.List; import java.util.Map;  public class MainActivity extends AppCompatActivity {      private static final int PERMISSIONS_REQUEST_CODE_ACCESS_COARSE_LOCATION = 1;//设置权限之后回调函数中用于区别不同权限回调的自定义常量值     String wifi_name;     int wifi_rssi;      //自定义一个数据类型，后面用于存储与排序     public class WifiStream     {         String WifiStream_name;         int WifiStream_rssi;          public WifiStream(String ssid, int level) {             this.WifiStream_name = ssid;             this.WifiStream_rssi = level;         }     }      ArrayAdapter<String> adapter;     List<String> WifiList = new ArrayList<>();     WifiManager wifiManager;//想要获得wifi信息就必须要一个WifiManager对象       @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);          //定义按键实例         Button button1=(Button) findViewById(R.id.wifi_rssi);         //定义按钮点击事件         button1.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                 //想要获得wifi信息就必须要一个WifiManager对象                 wifiManager= (WifiManager) getApplicationContext().getSystemService(WIFI_SERVICE);//获取wifi服务                 assert wifiManager != null;                  //创建WifiInfo对象                 WifiInfo wifiInfo=wifiManager.getConnectionInfo();                 wifi_name=wifiInfo.getSSID();                  //华为手机要通过下面代码才可以获得wifi名称                 int networkID=wifiInfo.getNetworkId();                 List<WifiConfiguration> configuredNetworks = wifiManager.getConfiguredNetworks();                 for (WifiConfiguration wifiConfiguration:configuredNetworks){                     if (wifiConfiguration.networkId==networkID){                         wifi_name=wifiConfiguration.SSID;                         break;                     }                 }                  wifi_rssi=wifiInfo.getRssi();                 //通过Toast输出                 Toast.makeText(MainActivity.this, "current WIFI:"+"rssi:"+wifi_rssi+"---wifiId:"+wifi_name,Toast.LENGTH_SHORT).show();              }         });           //////////////**************下面才是扫描wifi列表*********************/////////////////         //调用扫描wifi列表。调用的函数会返回wifi列表         //需要权限才可以获取wifi列表 //        registerPermission();//里面修改了WifiList         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && checkSelfPermission(                 Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {             requestPermissions(new String[] { Manifest.permission.ACCESS_COARSE_LOCATION }, PERMISSIONS_REQUEST_CODE_ACCESS_COARSE_LOCATION);          } else {             getWifiList();//调用上面函数获取wifi列表         }          //获取listview控件实例         ListView listwifiView=(ListView) findViewById(R.id.wifi_list_view);          //设置适配器对应listview         adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, WifiList);         listwifiView.setAdapter(adapter);          adapter.notifyDataSetChanged();//并通知刷新一下ListView      }       //扫描wifi列表     //通过wifiManager获取wifi列表     public void getWifiList() {         //定义一个WifiManager对象         WifiManager wifiManager = (WifiManager) getApplicationContext().getSystemService(WIFI_SERVICE);          List<ScanResult> scanWifiList = wifiManager.getScanResults();         List<ScanResult> wifiList = new ArrayList<>();//最终返回的列表           List <WifiStream> list = new ArrayList<WifiStream>();          if (scanWifiList != null && scanWifiList.size() > 0) {              for (int i = 0; i < scanWifiList.size(); i++) {                 ScanResult scanResult = scanWifiList.get(i);                 if (!scanResult.SSID.isEmpty()) {//wifi名称不是空的话                     String key = scanResult.SSID + " " + scanResult.level;//显示wifi的名称以及其RSSI                     list.add(new WifiStream(scanResult.SSID, scanResult.level));                  }             }         }         //通过Collections.sort(List , Comparator c)方法来进行排序         //按照rssi来排序         Collections.sort(list,comparator);          //然后将list转为string放入WifiList中         for (int i=0;i<list.size();i++){             String key=list.get(i).WifiStream_name+""+list.get(i).WifiStream_rssi;             WifiList.add(key);//输出key（wifi名称+RSSI）         }      }      @Override     public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {         super.onRequestPermissionsResult(requestCode, permissions, grantResults);         if (requestCode == PERMISSIONS_REQUEST_CODE_ACCESS_COARSE_LOCATION) {             getWifiList();         }     }      //按照rssi来排序(小到大排序)     static Comparator<WifiStream> comparator = new Comparator<WifiStream>() {         @Override         public int compare(WifiStream p1 , WifiStream p2 ) {             if( p1.WifiStream_rssi > p2.WifiStream_rssi ){                 return 1 ;  //正数             }else if ( p1.WifiStream_rssi < p2.WifiStream_rssi) {                 return -1 ;  //负数             }else {                 return 0;  //相等为0             }         }     }; //    private class SortRssi implements Comparator<WifiStream> { //        @Override //        public int compare(MainActivity.WifiStream o1, MainActivity.WifiStream o2) { //            return o1.WifiStream_rssi-o2.WifiStream_rssi; //        } //    } }  

最终的代码：

 package com.example.wifitest;  import androidx.annotation.NonNull; import androidx.appcompat.app.AppCompatActivity;  import android.Manifest; import android.content.Context; import android.content.pm.PackageManager; import android.net.ConnectivityManager; import android.net.NetworkInfo; import android.net.wifi.ScanResult; import android.net.wifi.WifiConfiguration; import android.net.wifi.WifiInfo; import android.net.wifi.WifiManager; import android.os.Build; import android.os.Bundle; import android.util.Log; import android.view.View; import android.widget.ArrayAdapter; import android.widget.Button; import android.widget.ListView; import android.widget.Toast;  import java.util.ArrayList; import java.util.Collections; import java.util.Comparator; import java.util.HashMap; import java.util.List; import java.util.Map;  public class MainActivity extends AppCompatActivity {      private static final int PERMISSIONS_REQUEST_CODE_ACCESS_COARSE_LOCATION = 1;//设置权限之后回调函数中用于区别不同权限回调的自定义常量值     String wifi_name;     int wifi_rssi;      //自定义一个数据类型，后面用于存储与排序     public class WifiStream     {         String WifiStream_name;         int WifiStream_rssi;          public WifiStream(String ssid, int level) {             this.WifiStream_name = ssid;             this.WifiStream_rssi = level;         }     }      ArrayAdapter<String> adapter;     List<String> WifiList = new ArrayList<>();     WifiManager wifiManager;//想要获得wifi信息就必须要一个WifiManager对象       @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);          //定义按键实例         Button button1=(Button) findViewById(R.id.wifi_rssi);         //定义按钮点击事件         button1.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                 //想要获得wifi信息就必须要一个WifiManager对象                 wifiManager= (WifiManager) getApplicationContext().getSystemService(WIFI_SERVICE);//获取wifi服务                 assert wifiManager != null;                  //创建WifiInfo对象                 WifiInfo wifiInfo=wifiManager.getConnectionInfo();                 wifi_name=wifiInfo.getSSID();                  //华为手机要通过下面代码才可以获得wifi名称                 int networkID=wifiInfo.getNetworkId();                 List<WifiConfiguration> configuredNetworks = wifiManager.getConfiguredNetworks();                 for (WifiConfiguration wifiConfiguration:configuredNetworks){                     if (wifiConfiguration.networkId==networkID){                         wifi_name=wifiConfiguration.SSID;                         break;                     }                 }                  wifi_rssi=wifiInfo.getRssi();                 //通过Toast输出                 Toast.makeText(MainActivity.this, "current WIFI:"+"rssi:"+wifi_rssi+"---wifiId:"+wifi_name,Toast.LENGTH_SHORT).show();              }         });           //////////////**************下面才是扫描wifi列表*********************/////////////////         //调用扫描wifi列表。调用的函数会返回wifi列表         //需要权限才可以获取wifi列表 //        registerPermission();//里面修改了WifiList         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && checkSelfPermission(                 Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {             requestPermissions(new String[] { Manifest.permission.ACCESS_COARSE_LOCATION }, PERMISSIONS_REQUEST_CODE_ACCESS_COARSE_LOCATION);          } else {             getWifiList();//调用上面函数获取wifi列表         }          //获取listview控件实例         ListView listwifiView=(ListView) findViewById(R.id.wifi_list_view);          //设置适配器对应listview         adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, WifiList);         listwifiView.setAdapter(adapter);          adapter.notifyDataSetChanged();//并通知刷新一下ListView      }       //扫描wifi列表     //通过wifiManager获取wifi列表     public void getWifiList() {         //定义一个WifiManager对象         WifiManager wifiManager = (WifiManager) getApplicationContext().getSystemService(WIFI_SERVICE);          List<ScanResult> scanWifiList = wifiManager.getScanResults();         List<ScanResult> wifiList = new ArrayList<>();//最终返回的列表           List <WifiStream> list = new ArrayList<WifiStream>();          if (scanWifiList != null && scanWifiList.size() > 0) {              for (int i = 0; i < scanWifiList.size(); i++) {                 ScanResult scanResult = scanWifiList.get(i);                 if (!scanResult.SSID.isEmpty()) {//wifi名称不是空的话                     String key = scanResult.SSID + " " + scanResult.level;//显示wifi的名称以及其RSSI                     list.add(new WifiStream(scanResult.SSID, scanResult.level));                  }             }         }         //通过Collections.sort(List , Comparator c)方法来进行排序         //按照rssi来排序         Collections.sort(list,comparator);          //然后将list转为string放入WifiList中         for (int i=0;i<list.size();i++){             String key=list.get(i).WifiStream_name+""+list.get(i).WifiStream_rssi;             WifiList.add(key);//输出key（wifi名称+RSSI）         }      }      @Override     public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {         super.onRequestPermissionsResult(requestCode, permissions, grantResults);         if (requestCode == PERMISSIONS_REQUEST_CODE_ACCESS_COARSE_LOCATION) {             getWifiList();         }     }      //按照rssi来排序(小到大排序。)     static Comparator<WifiStream> comparator = new Comparator<WifiStream>() {         @Override         public int compare(WifiStream p1 , WifiStream p2 ) {             if( p1.WifiStream_rssi > p2.WifiStream_rssi ){                 return 1 ;  //正数             }else if ( p1.WifiStream_rssi < p2.WifiStream_rssi) {                 return -1 ;  //负数             }else {                 return 0;  //相等为0             }         }     }; //    private class SortRssi implements Comparator<WifiStream> { //        @Override //        public int compare(MainActivity.WifiStream o1, MainActivity.WifiStream o2) { //            return o1.WifiStream_rssi-o2.WifiStream_rssi; //        } //    } }  

可以按照rssi的大小来排列wifi

参考资料

关于scanResult（https://blog.csdn.net/male09/article/details/70792657）

https://www.jianshu.com/p/bdcec333ba2b

对键值进行排序（https://www.cnblogs.com/avivahe/p/5657071.html）

关于Comparator（https://blog.csdn.net/scgyus/article/details/79454321）