Android4.4 获取WAN supportedBands、EARFCN信息

在Android 4.4上获取WAN supportedBands和EARFCN信息需要使用TelephonyManager类和ServiceState类。以下是获取WAN supportedBands和EARFCN信息的示例代码：

TelephonyManager tm = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
ServiceState serviceState = tm.getServiceState();
if (serviceState != null && serviceState.getRilDataRadioTechnology() == ServiceState.RIL_RADIO_TECHNOLOGY_LTE) {
    int earfcn = serviceState.getLteEarfcn();
    int band = serviceState.getLteBand();
    Log.d(TAG, "EARFCN: " + earfcn + ", Band: " + band);
}

这个代码段首先获取TelephonyManager的实例，然后获取ServiceState的实例。然后，它会检查设备是否连接到LTE网络。如果是，则获取EARFCN和Band信息并打印它们。请注意，此代码需要访问"android.permission.READ_PHONE_STATE"权限。