WiFi

https://blog.csdn.net/hanyejing/article/details/52621862
WiFi的五种状态
判断WIFI的五个状态
可以用WifiManager对象调用
WIFI_STATE_DISABLING 0 正在关闭中
WIFI_STATE_DISABLED 1 关闭
WIFI_STATE_ENABLING 2 正在打开中
WIFI_STATE_ENABLED 3 打开
WIFI_STATE_UNKNOWN 4 未知

需要申请的权限
android.permission.ACCESS_WIFI_STATE
链接WIFI信息
android.permission.ACCESS_NETWORK_STATE
判断WIFI的状态(是否联网)
android.permission.CHANGE_WIFI_STATE
WIFI的五个变化
android.permission.CHANGE_NETWORK_STATE
转换网络状态
android.permission.ACCESS_COARSE_LOCATION
android:name="android.permission.ACCESS_FINE_LOCATION
WIFI位置
StringBuffer的append是追加,insert插入

package com.example.wangye.androidwifitest1609c;

import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.net.wifi.ScanResult;
import android.net.wifi.WifiInfo;
import android.net.wifi.WifiManager;
import android.os.Bundle;
import android.provider.Settings;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import java.util.List;

public class MainActivity extends Activity {
Button bt1,bt2,bt3,bt4,bt5,bt6;
  TextView tx;
  WifiManager manager;
  BroadcastReceiver receiver = new BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {
      if(intent.getAction().equals(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION)){
        List<ScanResult> list = manager.getScanResults();
        StringBuffer buffer = new StringBuffer();
        for(int i = 0;i<list.size();i++){
          ScanResult scanResult = list.get(i);
          buffer.append("No."+i+"\n").append("BSSID:"+scanResult.BSSID)
              .append("\nSSID:"+scanResult.SSID)
              .append("\n频率："+scanResult.frequency)
              .append("\n功率："+scanResult.level).append("\n\n");
        }
        tx.setText(buffer.toString());
      }
    }
  };
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    registerReceiver(receiver,new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));
    init();
  }

  @Override
  protected void onStop() {
    super.onStop();
    unregisterReceiver(receiver);
  }

  void init(){
  manager = (WifiManager) getSystemService(WIFI_SERVICE);
    bt1 = (Button) findViewById(R.id.button);
    bt1.setOnClickListener(new OnClickListener() {
      @Override
      public void onClick(View v) {
        manager.setWifiEnabled(true);
      }
    });
    bt2 = (Button) findViewById(R.id.button2);
    bt2.setOnClickListener(new OnClickListener() {
      @Override
      public void onClick(View v) {
        manager.setWifiEnabled(false);
      }
    });
    bt3 = (Button) findViewById(R.id.button3);
    bt3.setOnClickListener(new OnClickListener() {
      @Override
      public void onClick(View v) {
        //判断WIFI的五个状态
//        WIFI_STATE_DISABLING  0   正在关闭中
//        WIFI_STATE_DISABLED   1   关闭
//        WIFI_STATE_ENABLING   2   正在打开中
//        WIFI_STATE_ENABLED    3   打开
//        WIFI_STATE_UNKNOWN    4   未知

//        int state= manager.getWifiState();
        //判断WIFI打开关闭两个状态
        if(manager.isWifiEnabled()){
          Toast.makeText(MainActivity.this,"WIFI已打开",Toast.LENGTH_LONG).show();
        }else{
          Toast.makeText(MainActivity.this,"WIFI已关闭",Toast.LENGTH_LONG).show();
        }
      }
    });
    bt4 = (Button) findViewById(R.id.button4);
    bt4.setOnClickListener(new OnClickListener() {
      @Override
      public void onClick(View v) {
        //扫描周边可用WIFI
       manager.startScan();
        tx.setText("正在扫描，请稍后...");
      }
    });
    bt5 = (Button) findViewById(R.id.button5);
    bt5.setOnClickListener(new OnClickListener() {
      @Override
      public void onClick(View v) {
        Intent i = new Intent(Settings.ACTION_WIFI_SETTINGS);
        startActivity(i);
      }
    });
    bt6 = (Button) findViewById(R.id.button6);
    bt6.setOnClickListener(new OnClickListener() {
      @Override
      public void onClick(View v) {
        WifiInfo info = manager.getConnectionInfo();
        StringBuffer buffer = new StringBuffer();
        buffer.append("当前获取的已连接WIFI信息：\n").append("接入点的BSSID："+info.getBSSID())
            .append("\nSSID:"+info.getSSID()).append("\nMAC地址："+info.getMacAddress())
            .append("\nIP地址："+info.getIpAddress()).append("\n网络ID："+info.getNetworkId());
        tx.setText(buffer.toString());
      }
    });
    tx = (TextView) findViewById(R.id.textView);
  }
}