PhoneStateListener Android坏值

Question

我在安卓系统上遇到了一个问题。我想知道这个设备是否连接到GSM网络，这样它就可以发送短信了。

我试过两种方法，结果都是一样的。在Moto G 4G上，我可以确定它是否有接入权限。在Redmi 4上，它总是返回false。

第一项：

public static boolean hasCellularAccess(Context context) {
    TelephonyManager telephonyManager = (TelephonyManager)context.getSystemService(Context.TELEPHONY_SERVICE);

    if(telephonyManager == null || telephonyManager.getAllCellInfo() == null || telephonyManager.getAllCellInfo().size() == 0){
        return false;
    }

    if (telephonyManager.getAllCellInfo().get(0) instanceof CellInfoLte){
        CellInfoLte cellInfoLte = (CellInfoLte)telephonyManager.getAllCellInfo().get(0);
        CellSignalStrength cellSignalStrengthGsm = cellInfoLte.getCellSignalStrength();
        return cellSignalStrengthGsm.getLevel() > 0;
    }

    CellInfoGsm cellinfogsm = (CellInfoGsm) telephonyManager.getAllCellInfo().get(0);
    CellSignalStrength cellSignalStrengthGsm = cellinfogsm.getCellSignalStrength();
    return cellSignalStrengthGsm.getLevel() > 0;
}

第二项：

public class CustomPhoneListener extends PhoneStateListener {
private static final String TAG = "PhoneListener";

@Override
public void onSignalStrengthsChanged(SignalStrength signalStrength) {
    super.onSignalStrengthsChanged(signalStrength);
    Log.i(TAG, "onSignalStrengthsChanged: " + signalStrength);
    if (signalStrength.isGsm()) {
        Log.i(TAG, "onSignalStrengthsChanged: getGsmSignalStrength "
                + signalStrength.getGsmSignalStrength() + signalStrength);
    }
    try {

        Method[] methods = android.telephony.SignalStrength.class
                .getMethods();
        for (Method mthd : methods) {
            if (mthd.getName().equals("getLteSignalStrength")) {
                Log.i(TAG,
                        "onSignalStrengthsChanged: " + mthd.getName() + " "
                                + mthd.invoke(signalStrength));
            }
        }
    } catch (SecurityException | IllegalArgumentException | InvocationTargetException | IllegalAccessException e) {
        e.printStackTrace();
    }

}}

在雷德米号上：

SignalStrength: 0 48 -120 -160 -7 0 -1 99 -93 -6 282 2147483647 ==>值99未知

在Moto号上：

SignalStrength: 99 0 -120 -160 -120 -1 -1 18 -109 -8 116 2147483647 2147483647 0到31之间的==>值是可以的。

以前有人面对过这个问题并解决了吗？我已经读到，这个问题也存在于一些三星银河。

谢谢！

Answer 1

起作用了！

这是我的最后一部作品，行得通。如果手机有很大的正常运行时间值，API似乎会返回坏的值。

public static boolean hasCellularAccess(Context context) {
    TelephonyManager telephonyManager = (TelephonyManager)context.getSystemService(Context.TELEPHONY_SERVICE);
    if(telephonyManager == null || telephonyManager.getAllCellInfo() == null || telephonyManager.getAllCellInfo().size() == 0){
        return false;
    }

    if (telephonyManager.getAllCellInfo().get(0) instanceof CellInfoLte){
        CellInfoLte cellInfoLte = (CellInfoLte)telephonyManager.getAllCellInfo().get(0);
        CellSignalStrength cellSignalStrengthGsm = cellInfoLte.getCellSignalStrength();
        return cellSignalStrengthGsm.getLevel() > 0;
    }

    if(telephonyManager.getAllCellInfo().get(0) instanceof CellInfoGsm){
        CellInfoGsm cellinfogsm = (CellInfoGsm) telephonyManager.getAllCellInfo().get(0);
        CellSignalStrength cellSignalStrengthGsm = cellinfogsm.getCellSignalStrength();
        return cellSignalStrengthGsm.getLevel() > 0;
    }else {
        CellInfoWcdma cellinfogsm = (CellInfoWcdma) telephonyManager.getAllCellInfo().get(0);
        CellSignalStrength cellSignalStrengthGsm = cellinfogsm.getCellSignalStrength();
        return cellSignalStrengthGsm.getLevel() > 0;
    }
}