35

我想在点击 API 调用时获得设备的信号强度。我已经搜索了所有相关线程，但我还没有成功。

所以我想得到像这样的信号强度

SignalStrength ss = null  ; // some initialization

int n = ss.getGsmSignalStrength();

但是在使用这个的时候，很明显我会得到空指针异常，因为我已经初始化SignalStrength为空了。但我不知道如何初始化它。

我也不想使用它，PhoneStateListener因为它仅在信号更改时才会触发。

我正在使用以下代码获取信号强度

TelephonyManager telephonyManager = (TelephonyManager)this.getSystemService(Context.TELEPHONY_SERVICE);
CellInfoGsm cellinfogsm = (CellInfoGsm)telephonyManager.getAllCellInfo().get(0);
CellSignalStrengthGsm cellSignalStrengthGsm = cellinfogsm.getCellSignalStrength();
cellSignalStrengthGsm.getDbm();

但我不想使用CellSignalStrength，因为它只在 API Level 17 中添加，并且在 17 下无法使用。我希望代码在 API Level 7+ 上工作。

或者有没有其他方法可以让我在调用 API 时获得信号强度？

4

9 回答 9

29

定义变量：

TelephonyManager mTelephonyManager;
MyPhoneStateListener mPhoneStatelistener;   
int mSignalStrength = 0;

然后将此类添加到您的代码中：

class MyPhoneStateListener extends PhoneStateListener {

     @Override
     public void onSignalStrengthsChanged(SignalStrength signalStrength) {
         super.onSignalStrengthsChanged(signalStrength);
         mSignalStrength = signalStrength.getGsmSignalStrength();
         mSignalStrength = (2 * mSignalStrength) - 113; // -> dBm           
     }
 }

并在您的onCreate方法中使用：

mPhoneStatelistener = new MyPhoneStateListener();
mTelephonyManager = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
mTelephonyManager.listen(mPhoneStatelistener, PhoneStateListener.LISTEN_SIGNAL_STRENGTHS);
于 2014-09-26T10:50:12.157 回答
6

全局定义：

TelephonyManager telephonyManager;
myPhoneStateListener psListener;
TextView txtSignalStr;

onCreate方法 ：

@Override
protected void onCreate(final Bundle savedInstanceState) {
 txtSignalStr = (TextView)findViewById(R.id.signalStrength);
 psListener = new myPhoneStateListener();
 telephonyManager = (TelephonyManager)getActivity().getSystemService(Context.TELEPHONY_SERVICE);
 telephonyManager.listen(psListener,PhoneStateListener.LISTEN_SIGNAL_STRENGTHS);
}

创建myPhoneStateListener类：

public class myPhoneStateListener extends PhoneStateListener {
    public int signalStrengthValue;

    public void onSignalStrengthsChanged(SignalStrength signalStrength) {
        super.onSignalStrengthsChanged(signalStrength);
        if (signalStrength.isGsm()) {
            if (signalStrength.getGsmSignalStrength() != 99)
                signalStrengthValue = signalStrength.getGsmSignalStrength() * 2 - 113;
            else
                signalStrengthValue = signalStrength.getGsmSignalStrength();
        } else {
            signalStrengthValue = signalStrength.getCdmaDbm();
        }
        txtSignalStr.setText("Signal Strength : " + signalStrengthValue);
    }
}
于 2015-06-19T12:01:35.610 回答
5 
public class PhoneCustomStateListener extends PhoneStateListener {

    public int signalSupport = 0;

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

        signalSupport = signalStrength.getGsmSignalStrength();
        Log.d(getClass().getCanonicalName(), "------ gsm signal --> " + signalSupport);

        if (signalSupport > 30) {
            Log.d(getClass().getCanonicalName(), "Signal GSM : Good");


        } else if (signalSupport > 20 && signalSupport < 30) {
            Log.d(getClass().getCanonicalName(), "Signal GSM : Avarage");


        } else if (signalSupport < 20 && signalSupport > 3) {
            Log.d(getClass().getCanonicalName(), "Signal GSM : Weak");


        } else if (signalSupport < 3) {
            Log.d(getClass().getCanonicalName(), "Signal GSM : Very weak");


        }
    }
}
于 2017-03-08T15:13:15.243 回答
4

我们不应该初始化信号强度，而是使用电话监听器并覆盖方法 onSignalStrengthsChanged(SignalStrength signalStrength)。

例如，看看下面的代码片段

class SamplePhoneStateListener extends PhoneStateListener {

        int signalStrength = 0;

        @Override
        public void onSignalStrengthsChanged(SignalStrength signalStrength) {
            super.onSignalStrengthsChanged(signalStrength);
            signalStrength = signalStrength.getGsmSignalStrength();
            //You can check the signal strength value here..
        }

    }

使用 TelephonyManager 对象，您可以收听上面的类，例如

TelephonyManagerObject.listen(myListener,
            PhoneStateListener.LISTEN_SIGNAL_STRENGTHS)
于 2014-07-22T21:41:53.470 回答
2

这对我有用：

需要哪些服务：

ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);

TelephonyManager telephonyManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);

如何收集指标：

public void startGatherMetrics() {
    NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();
    if (networkInfo != null) {
        networkInfoStr = connectivityManager.getActiveNetworkInfo().toString();

        // gather Network Capabilities
        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.M) {
            Network network = connectivityManager.getActiveNetwork();
            networkInfoStr += "; " + connectivityManager.getNetworkCapabilities(network).toString();
        }
    }
    Log.d("A_NETWORK_INFO", networkInfoStr);

    new Thread(new Runnable() {
        @Override
        public void run() {
            quitLooper = false;
            Looper.prepare();
            telephonyManager.listen(new PhoneStateListener() {
                @Override
                public void onSignalStrengthsChanged(SignalStrength signalStrength) {
                    super.onSignalStrengthsChanged(signalStrength);
                    Log.d("A_NETWORK_METRICS",
                        "Signal Strength (0-4 / dBm):" + getLevel(signalStrength) + " / "
                            + getDbm(signalStrength));

                    if (quitLooper)
                        Looper.myLooper().quit();
                }
            }, PhoneStateListener.LISTEN_SIGNAL_STRENGTHS);

            Looper.loop();
        }
    }).start();

}

public void stop() {
    quitLooper = true;
}

“ getLevel(signalStrength) ”和“ getDbm(signalStrength) ”可以在这里找到。

于 2018-06-22T14:26:14.183 回答
1

您不实例化 SignalStrength（可能您不能）。从应用程序代码。

您必须使用 PhoneStateListener（子类），并实现 onSignalStrengthsChanged：

http://developer.android.com/reference/android/telephony/PhoneStateListener.html#onSignalStrengthsChanged(android.telephony.SignalStrength)

将为您创建一个 SignalStrength 并将其传递给您的覆盖。

于 2014-04-26T14:41:59.180 回答
1

科特林版本：

class myPhoneStateListener : PhoneStateListener() {
    var signalStrengthValue = 0
    override fun onSignalStrengthsChanged(signalStrength: SignalStrength) {
        super.onSignalStrengthsChanged(signalStrength)
        signalStrengthValue = if (signalStrength.isGsm) {
            if (signalStrength.gsmSignalStrength != 99) signalStrength.gsmSignalStrength * 2 - 113 else signalStrength.gsmSignalStrength
        } else {
            signalStrength.cdmaDbm
        }
        txtSignalStr.setText("Signal Strength : $signalStrengthValue")
    }
}
于 2020-06-05T15:04:28.057 回答
0

PhoneStateListener 对象应该在 Looper 线程中实例化。因此，如果您使用的是工作线程（非 GUI 线程），则可以使用以下内容；

private HandlerThread handlerThreadCellularSignal = null;

public void startListen() {     
        handlerThreadCellularSignal = new HandlerThread("CELLULAR_INFO_THREAD");
        handlerThreadCellularSignal.start();
        Looper looper = handlerThreadCellularSignal.getLooper();
        Handler handler = new Handler(looper);
        handler.post(new Runnable() {
            @Override
            public void run() {
                phoneStatelistener = new PhoneStateListenerEx();
                TelephonyManager telephonyManager = (TelephonyManager) getContext().getSystemService(Context.TELEPHONY_SERVICE);
                telephonyManager.listen(phoneStatelistener, PhoneStateListener.LISTEN_SIGNAL_STRENGTHS);
            }
        });
}

private void stopListen() {
    handlerThreadCellularSignal.quit();
}


public class PhoneStateListenerEx extends PhoneStateListener {

    @Override
    public void onSignalStrengthsChanged(SignalStrength signalStrength) {
        super.onSignalStrengthsChanged(signalStrength);
        int signalStrengthdBm = (2 * signalStrength.getGsmSignalStrength()) - 113; // -> dBm
        Log.d("Cellular Signal Strength | " + String.valueOf(signalStrengthdBm));
    }
}
于 2019-08-07T09:46:02.950 回答
0 
public class myPhoneStateListener extends PhoneStateListener {
    public int signalStrengthValue;

    public void onSignalStrengthsChanged(SignalStrength signalStrength) {
        super.onSignalStrengthsChanged(signalStrength);
        if (signalStrength.isGsm()) {
            if (signalStrength.getGsmSignalStrength() != 99)
                signalStrengthValue = signalStrength.getGsmSignalStrength() * 2 - 113;
            else
                signalStrengthValue = signalStrength.getGsmSignalStrength();
        } else {
            signalStrengthValue = signalStrength.getCdmaDbm();
        }
        txtSignalStr.setText("Signal Strength : " + signalStrengthValue);
    }
}
于 2020-06-05T14:40:31.313 回答