网上爬到的获取wifi强度方法。
 
可以获取wifi信号强度， 3, 2 ,1
 

//    UIApplication *app = [UIApplication sharedApplication];
//    NSArray *subviews = [[[app valueForKey:@"statusBar"] valueForKey:@"foregroundView"] subviews];
//    NSString *dataNetworkItemView = nil;
//    
//    for (id subview in subviews) {
//        if([subview isKindOfClass:[NSClassFromString(@"UIStatusBarDataNetworkItemView") class]]) {
//            dataNetworkItemView = subview;
//            break;
//        }
//    }
//    
//    int signalStrength = [[dataNetworkItemView valueForKey:@"_wifiStrengthBars"] intValue];
//    
//    NSLog(@"signal %d", signalStrength);

因为业务需要，获取到手机主板的信号强度，包括WiFi，4G，2G。来验证当前主板模块是否是因为信号不好而导致问题，我去网上查询了几遍，将一些文章结合起来。最后获取到相关数据。以下是相关的操作步骤
 
 
 
1.加权限
 
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE"/>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
 
2.实例化TelephonyManager，建立起PhoneStatListener监听（主要是带SIM卡的状态监听），再注册一个NetWorkBroadCastReceiver监听。
 
//获取telephonyManager
mTelephonyManager = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
//开始监听
mListener = new PhoneStatListener();
mNetWorkBroadCastReciver = new NetWorkBroadCastReciver();
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
intentFilter.addAction(WifiManager.NETWORK_STATE_CHANGED_ACTION);
intentFilter.addAction(WifiManager.WIFI_STATE_CHANGED_ACTION);
intentFilter.addAction(WifiManager.RSSI_CHANGED_ACTION);
registerReceiver(mNetWorkBroadCastReciver, intentFilter);
 
 
 
mTelephonyManager.listen(mListener, PhoneStatListener.LISTEN_SIGNAL_STRENGTHS);
 
/**
 * 观察手机带SIM卡时的信号强度
 */
private class PhoneStatListener extends PhoneStateListener {
    //获取信号强度

    @Override
    public void onSignalStrengthsChanged(SignalStrength signalStrength) {
        super.onSignalStrengthsChanged(signalStrength);

        signal=signalStrength;
        //网络信号改变时，获取网络信息
        getNetWorkInfo();
    }
}
 
//接收网络状态改变的广播
class NetWorkBroadCastReciver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        getNetWorkInfo();
    }
}
 
  /**
     * 获取网络的信息
     */
    private void getNetWorkInfo() {
        ConnectivityManager connectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo info = connectivityManager.getActiveNetworkInfo();
        if (info != null && info.isAvailable()) {
            switch (info.getType()) {
                case ConnectivityManager.TYPE_WIFI:
                    //wifi
                    WifiManager manager = (WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE);
                    WifiInfo connectionInfo = manager.getConnectionInfo();
                    int rssi = connectionInfo.getRssi();
                    mTextView.setText("当前为wifi网络，信号强度=" + rssi);
                    break;
                case ConnectivityManager.TYPE_MOBILE:
                    //移动网络,可以通过TelephonyManager来获取具体细化的网络类型
                    String netWorkStatus = isFastMobileNetwork() ? "4G网络" : "2G网络";
                    if (isFastMobileNetwork()){
                        try {
                            if (signal==null){
                                Log.e("tiwolf", "getNetWorkInfo: signal为空" );
                                return;
                            }
                         
                            Method method=signal.getClass().getMethod("getDbm");
                            mGsmSignalStrength= (int) method.invoke(signal);
                            if(mGsmSignalStrength>-90){
                                Log.e("tiwolf", "getNetWorkInfo: 信号强度强" );
                            }else {
                                Log.e("tiwolf", "getNetWorkInfo: 信号强度弱" );
                            }
                        } catch (NoSuchMethodException e) {
                            e.printStackTrace();
                        } catch (IllegalAccessException e) {
                            e.printStackTrace();
                        } catch (InvocationTargetException e) {
                            e.printStackTrace();
                        }

                    }else {
                        //获取网络信号强度
                        //获取0-4的5种信号级别，越大信号越好,但是api23开始才能用
//            int level = signalStrength.getLevel();
                        if (signal==null){
                            Log.e("tiwolf", "getNetWorkInfo: signal为空" );
                            return;
                        }
                        mGsmSignalStrength = signal.getGsmSignalStrength();
                    }
                    mTextView.setText("当前为" + netWorkStatus + "，信号强度=" + mGsmSignalStrength);
                    Log.e("tiwolf", "当前为" + netWorkStatus + "，信号强度=" + mGsmSignalStrength );
                    break;
            }
        } else {
            mTextView.setText("没有可用网络");
        }
    }
 
最后结束取消监听，取消注册
 
mTelephonyManager.listen(mListener, PhoneStatListener.LISTEN_NONE);
 
unregisterReceiver(mNetWorkBroadCastReciver);
 
 
 
大体的就是这样子，后面有文档上传到csdn，有需要的可以去下载
 
 
 
 
 
 
 
 
 
 
 
 

1、获得WifiManager对象
 
WifiManager wm = (WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE);
 
2、通过WifiManager对象获得wifi信息
 
WifiInfo info = wm.getConnectionInfo();
 
3、通过WifiInfo获得wifi信息
 
//通过wifi管理对象获得wifi信息
                        WifiInfo info = wm.getConnectionInfo();
                        //获取wifi名称
                        String ssid = info.getSSID().replace("\"", "");
                        //获取mac地址
                        String MacAddr = info.getMacAddress();
                        //获取当前连接速度
                        int linkSpeed = info.getLinkSpeed();
                        //获取ip地址
                        int ipAddr = info.getIpAddress();
                        ......
 
xml代码
 
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="20dp"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="SSID:"
        android:textColor="@android:color/black"
        android:textSize="30sp" />

    <TextView
        android:id="@+id/wifiSSID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_toRightOf="@id/textView1"
        android:text="-"
        android:textColor="@android:color/black"
        android:textSize="30sp" />

    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="信号强度"
        android:layout_below="@id/textView1"
        android:textColor="@android:color/black"
        android:textSize="30sp" />

    <ImageView
        android:id="@+id/ivWifi"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/textView2"
        android:background="@drawable/wifi1"/>

</RelativeLayout>
 
主函数代码
 
import android.app.Activity;
import android.content.Context;
import android.net.wifi.WifiInfo;
import android.net.wifi.WifiManager;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {

    private WifiManager wm;
    private TextView wifiSSID;
    private ImageView ivWifi;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initView();
        initWifi();
    }

    private void initView() {
        wifiSSID = findViewById(R.id.wifiSSID);
        ivWifi = findViewById(R.id.ivWifi);
    }

    Handler handler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
                case 1:
                    wifiSSID.setText(msg.obj.toString());
                    if (msg.arg1 <= 50) {
                        ivWifi.setBackgroundResource(R.drawable.wifi4);
                    } else if (msg.arg1 <= 70) {
                        ivWifi.setBackgroundResource(R.drawable.wifi3);
                    } else if (msg.arg1 <= 100) {
                        ivWifi.setBackgroundResource(R.drawable.wifi2);
                    }
                    break;
                case 2:
                    wifiSSID.setText("-");
                    ivWifi.setBackgroundResource(R.drawable.wifi1);
                    break;
            }
        }
    };

    private void initWifi() {
        Thread thread = new Thread() {
            @Override
            public void run() {
                while (true) {
                    try {
                        sleep(1000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    //拿到wifi管理对象
                    wm = (WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE);
                    if (wm.isWifiEnabled()) {
                        //通过wifi管理对象获得wifi信息
                        WifiInfo info = wm.getConnectionInfo();
                        //获取wifi名称
                        String ssid = info.getSSID().replace("\"", "");
                        //获取mac地址
                        String MacAddr = info.getMacAddress();
                        //获取当前连接速度
                        int linkSpeed = info.getLinkSpeed();
                        //获取ip地址
                        int ipAddr = info.getIpAddress();

                        Message msg = Message.obtain();
                        msg.what = 1;
                        msg.obj = ssid;
                        /**
                        *	getRssi()返回的是一个-100到0的数，直接取绝对值
                        *	-50到0表示信号好
                        *	-50到-70表示信号一般
                        *	-70到-100表示信号差
                        */
                        msg.arg1 = Math.abs(info.getRssi());
                        handler.sendMessage(msg);
                    } else {
                        Message msg = Message.obtain();
                        msg.what = 2;
                        handler.sendMessage(msg);
                    }
                }
            }
        };
        thread.start();
    }


}

 
最后给权限
 
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"></uses-permission>

连接上当前的wifi以后，需要知道当前wifi的信号强度，就是wifiinfo.getRssi()；这个方法，而rssi的范围为0到-100，
 
WifiManager mWifiManager = (WifiManager) mContext.getSystemService(Context.WIFI_SERVICE);
            WifiInfo mWifiInfo = mWifiManager.getConnectionInfo();
            int wifi = mWifiInfo.getRssi();//获取wifi信号强度
            if (wifi > -50 && wifi < 0) {//最强
                Log.e(TAG, "最强");
            } else if (wifi > -70 && wifi < -50) {//较强
                Log.e(TAG, "较强");
            } else if (wifi > -80 && wifi < -70) {//较弱
                Log.e(TAG, "较弱");
            } else if (wifi > -100 && wifi < -80) {//微弱
                Log.e(TAG, "微弱");
            }
 
这样就区分出来信号的强弱了