Android 5+ how to change preferred network

Question

Hi I have read a lot about this argument, but I think there is a lot of mistake to how can change preferred network in android 5+.
First of all my app can use root, but as a requisite it must be stay in play store .

To do this I think there is three methods:

with root
sign your app with system app cert
sign your app with a carrier permission

For the second method there is some big problems:

You cannot publish in play store your app signed with system cert
App with system cert connot be installed on certain devices (such es Huawei)

For the third method, the problem is that Vodafone is not my friends :)

So, let's talking about the first method:

Inside play store there are a lot of app that can change preferred network with root permision, an exmaple is Auotomate: https://play.google.com/store/apps/details?id=com.llamalab.automate.ext.superuser&hl=it
I think all applciation call with reflection in root session this function from internal API : https://github.com/android/platform_frameworks_base/blob/nougat-mr1-release/telephony/java/com/android/internal/telephony/ITelephony.aidl#L753
So I have try to do this with this code... but freeze my application:

/**
 * Function that change the preffered network
 * @param Context context - The context of application
 * @param String state_network - State that you want change ["2G" "3G" "4G" "2G/3G" "2G/3G/4G"]
 * @return boolean
 */
public static String setDeviceNetwork(Context context, String state_network){
    try {
        Process process = null;
        process = Runtime.getRuntime().exec("su");
        process.waitFor();
        TelephonyManager telephonyManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);

        try{
            Class<?> forName = Class.forName("com.android.internal.telephony.PhoneFactory");
            try {
                Method getDefaultPhone = forName.getMethod("getDefaultPhone", new Class[]{});
                getDefaultPhone.setAccessible(true);
                try {
                    Object mPhone = getDefaultPhone.invoke(null, new Object[]{}); //@TODO qui!
                    Method setPreferredNetworkType = mPhone.getClass().getMethod("setPreferredNetworkType", new Class[]{int.class, Message.class});
                    Method getPreferredNetworkType = mPhone.getClass().getMethod("getPreferredNetworkType", new Class[]{Message.class});
                    setPreferredNetworkType.setAccessible(true);
                    setPreferredNetworkType.invoke(mPhone, new Object[]{1, "1"});
                    return "WORK!";
                }catch (IllegalAccessException e){
                    return "Error IllegalAccessException on run command change network";
                }catch (InvocationTargetException e){
                    return "Error InvocationTargetException on run command change network";
                }
            }catch (NoSuchMethodException e){
                return "Error NoSuchMethodException on find method";
            }
        }catch (ClassNotFoundException e){
            return "Error ClassNotFoundException on find class";
        }
    } catch (IOException e) {
        e.printStackTrace();
        return "Error IOException on sudo command";
    }
    catch (InterruptedException e) {
        e.printStackTrace();
        return "Error InterruptException on sudo command";
    }
}

Any solution about this problem?

I think it freeze because process.waitFor(); don't return Su — r1si, Feb 11 '17 at 11:10

Android 5+ how to change preferred network

0 Answers0