Java 在 Android 中获取网络连接警告

我试图通过编程检测，当Android手机触发此"警告"时，当前无法访问已建立的internet连接(在本例中为Edge/2G)，如下所示:

事实上，当这个警告出现时，互联网就无法访问，没有它，互联网就会正常工作.

我目前正在做的是检测正确的网络:

public String getNetworkClass() {

    if (ActivityCompat.checkSelfPermission(context, Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED) {
        return "Unknown";
    } else {
        int networkType = mTelephonyManager.getNetworkType();
        Log.i("NETWORK", String.valueOf(networkType));
        mobileNetworkType = networkType;

        switch (networkType) {
            case TelephonyManager.NETWORK_TYPE_GPRS:
            case TelephonyManager.NETWORK_TYPE_EDGE:
            case TelephonyManager.NETWORK_TYPE_CDMA:
            case TelephonyManager.NETWORK_TYPE_1xRTT:
            case TelephonyManager.NETWORK_TYPE_IDEN:
                return "2G";
            case TelephonyManager.NETWORK_TYPE_UMTS:
            case TelephonyManager.NETWORK_TYPE_EVDO_0:
            case TelephonyManager.NETWORK_TYPE_EVDO_A:
            case TelephonyManager.NETWORK_TYPE_HSDPA:
            case TelephonyManager.NETWORK_TYPE_HSUPA:
            case TelephonyManager.NETWORK_TYPE_HSPA:
            case TelephonyManager.NETWORK_TYPE_EVDO_B:
            case TelephonyManager.NETWORK_TYPE_EHRPD:
            case TelephonyManager.NETWORK_TYPE_HSPAP:
                return "3G";
            case TelephonyManager.NETWORK_TYPE_LTE:
                return "4G";
            case TelephonyManager.NETWORK_TYPE_NR:
                return "5G";
            default:
                return "Unknown";
        }
    }
}

当它是2G时，我正在测量下载/上传速率.我将自己定位为here，猜测下载速率低于150 kbps可能会导致"警告":

if(Arrays.asList(new String[]{"2G"}).contains(getNetworkClass())) {
    ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkCapabilities nc = cm.getNetworkCapabilities(cm.getActiveNetwork());
    int downSpeed = nc.getLinkDownstreamBandwidthKbps();
    int upSpeed = nc.getLinkUpstreamBandwidthKbps();
    

    if(downSpeed < 150) {
        // I assume the connection is bad here                            
    } else {
        // All fine!
    }

但是，我的测量值在30到100 kbps之间(每五秒钟一次)，有时在此范围内，会出现警告，有时则不会.

我如何才能成功地捕捉到这一点？是否有任何Android界面来判断这一点？如果可能，我想进行avoid次ping判断，如:

public boolean canAccessInternet() {
    Runtime runtime = Runtime.getRuntime();
    try {
        Process ipProcess = runtime.exec("/system/bin/ping -c 1 8.8.8.8");
        int exitValue = ipProcess.waitFor();
        System.out.println("Network mExitValue " + exitValue);
        return (exitValue == 0);
    } catch (IOException e) {
        System.out.println(" IO Error ");
        e.printStackTrace();
    } catch (InterruptedException e) {
        System.out.println(" Interrupted Error ");
        e.printStackTrace();
    }
    return false;
}