getNetworkInfo

I try getNetworkInfo().
I get ConnectivityManager class.

ConnectivityManager cm = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE);

I get NetworkInfo class, this is TYPE_MOBILE sample.

NetworkInfo ni = cm.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);

In Wifi and mobile active, I try setNetworkPrefernce(), I expect change network interface changing. but No change.

cm.setNetworkPreference(ConnectivityManager.TYPE_MOBILE);

If you use setNetworkPreference(), you must add CHANGE_NETWORK_STATE feature.
source code is here.
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