[RadioInfo] Save PreferredNetworkMode to Settings

Historically, the debug menu intentionally did not
save the preferred network mode once chosen. This
causes problems because some settings cause a phone
switch which overrides the preferred network mode,
which can cause another phone switch and again
override the preferred network mode, completely
obliterating the requested debug setting. This change
will now save the debug menu setting to the system
settings, which will prevent the circular changes and
loss of setting due to phone switching.

However, caching the debug setting to prevent the phone
switch logic from overriding the setting has a side
effect, which is why it wasn't done historically.
If a debug setting of the preferred network mode
is set, it will cause the UX of the non-debug network
preference screen to change. Thus, someone who uses
the debug menu to make changes must be careful to
re-set the setting to return to the correct UX of the
publicly displayed menu.

Bug: 95133265
Test: -manually set preferred network mode using the
       RadioInfo menu and observed that there is no
       phone switch when setting CDMA.
      -confirmed that changing the network mode in
       RadioInfo will cause UX changes to the public
       network preference menu.

Change-Id: I91f669956a6d02515530855c4617cd0a767d73fa

diff --git a/src/com/android/settings/RadioInfo.java b/src/com/android/settings/RadioInfo.java
index 170db16..5d3afa5 100644 (file)
--- a/src/com/android/settings/RadioInfo.java
+++ b/src/com/android/settings/RadioInfo.java
@@ -17,6 +17,7 @@
 package com.android.settings;
 
 import static android.net.ConnectivityManager.NetworkCallback;
+import static android.provider.Settings.Global.PREFERRED_NETWORK_MODE;
 
 import android.app.Activity;
 import android.app.AlertDialog;
@@ -39,6 +40,7 @@ import android.os.AsyncResult;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.Message;
+import android.provider.Settings;
 import android.telephony.CarrierConfigManager;
 import android.telephony.CellInfo;
 import android.telephony.CellInfoCdma;
@@ -1489,6 +1491,19 @@ public class RadioInfo extends Activity {
             if (mPreferredNetworkTypeResult != pos && pos >= 0
                     && pos <= mPreferredNetworkLabels.length - 2) {
                 mPreferredNetworkTypeResult = pos;
+
+                // TODO: Possibly migrate this to TelephonyManager.setPreferredNetworkType()
+                // which today still has some issues (mostly that the "set" is conditional
+                // on a successful modem call, which is not what we want). Instead we always
+                // want this setting to be set, so that if the radio hiccups and this setting
+                // is for some reason unsuccessful, future calls to the radio will reflect
+                // the users's preference which is set here.
+                final int subId = phone.getSubId();
+                if (SubscriptionManager.isUsableSubIdValue(subId)) {
+                    Settings.Global.putInt(phone.getContext().getContentResolver(),
+                            PREFERRED_NETWORK_MODE + subId, mPreferredNetworkTypeResult);
+                }
+                log("Calling setPreferredNetworkType(" + mPreferredNetworkTypeResult + ")");
                 Message msg = mHandler.obtainMessage(EVENT_SET_PREFERRED_TYPE_DONE);
                 phone.setPreferredNetworkType(mPreferredNetworkTypeResult, msg);
             }