Add toggle for Wi-Fi hotspot

- Add Wi-Fi hotspot toggle with vertical divider

- Disable preference and toggle when Data Saver is enabled

Bug: 245569117
Test: manual test
make RunSettingsRoboTests ROBOTEST_FILTER=TetherSettingsTest
make RunSettingsRoboTests ROBOTEST_FILTER=WifiTetherPreferenceControllerTest
atest -c TetheringManagerModelTest

Change-Id: Ic2baf7d3d0a7bf9527da38d24ecc511b7c91265a

src/com/android/settings/network/tether/TetherSettings.java

@@ -96,11 +96,12 @@ public class TetherSettings extends RestrictedSettingsFragment
     private static final String TAG = "TetheringSettings";
     private static final boolean DEBUG = Log.isLoggable(TAG, Log.DEBUG);
 
-    private RestrictedSwitchPreference mUsbTether;
-
-    private SwitchPreference mBluetoothTether;
-
-    private SwitchPreference mEthernetTether;
+    @VisibleForTesting
+    RestrictedSwitchPreference mUsbTether;
+    @VisibleForTesting
+    SwitchPreference mBluetoothTether;
+    @VisibleForTesting
+    SwitchPreference mEthernetTether;
 
     private BroadcastReceiver mTetherChangeReceiver;
     private BroadcastReceiver mBluetoothStateReceiver;
@@ -115,7 +116,8 @@ public class TetherSettings extends RestrictedSettingsFragment
     private EthernetListener mEthernetListener;
     private final HashSet<String> mAvailableInterfaces = new HashSet<>();
 
-    private WifiTetherPreferenceController mWifiTetherPreferenceController;
+    @VisibleForTesting
+    WifiTetherPreferenceController mWifiTetherPreferenceController;
 
     private boolean mUsbConnected;
     private boolean mMassStorageActive;
@@ -125,7 +127,8 @@ public class TetherSettings extends RestrictedSettingsFragment
 
     private DataSaverBackend mDataSaverBackend;
     private boolean mDataSaverEnabled;
-    private Preference mDataSaverFooter;
+    @VisibleForTesting
+    Preference mDataSaverFooter;
 
     @VisibleForTesting
     String[] mUsbRegexs;
@@ -146,10 +149,10 @@ public class TetherSettings extends RestrictedSettingsFragment
     @Override
     public void onAttach(Context context) {
         super.onAttach(context);
-        mWifiTetherPreferenceController =
-                new WifiTetherPreferenceController(context, getSettingsLifecycle());
         TetheringManagerModel model = new ViewModelProvider(this).get(TetheringManagerModel.class);
-        mTm = model.mTetheringManager;
+        mWifiTetherPreferenceController =
+                new WifiTetherPreferenceController(context, getSettingsLifecycle(), model);
+        mTm = model.getTetheringManager();
         model.getTetheredInterfaces().observe(this, this::onTetheredInterfacesChanged);
     }
 
@@ -248,6 +251,7 @@ public class TetherSettings extends RestrictedSettingsFragment
     @Override
     public void onDataSaverChanged(boolean isDataSaving) {
         mDataSaverEnabled = isDataSaving;
+        mWifiTetherPreferenceController.setDataSaverEnabled(mDataSaverEnabled);
         mUsbTether.setEnabled(!mDataSaverEnabled);
         mBluetoothTether.setEnabled(!mDataSaverEnabled);
         mEthernetTether.setEnabled(!mDataSaverEnabled);

src/com/android/settings/network/tether/TetheringManagerModel.java

@@ -34,6 +34,7 @@ public class TetheringManagerModel extends AndroidViewModel {
     protected TetheringManager mTetheringManager;
     protected EventCallback mEventCallback = new EventCallback();
     protected MutableLiveData<List<String>> mTetheredInterfaces = new MutableLiveData<>();
+    protected StartTetheringCallback mStartTetheringCallback = new StartTetheringCallback();
 
     public TetheringManagerModel(@NonNull Application application) {
         super(application);
@@ -62,6 +63,27 @@ public class TetheringManagerModel extends AndroidViewModel {
         return Transformations.distinctUntilChanged(mTetheredInterfaces);
     }
 
+    /**
+     * Starts tethering and runs tether provisioning for the given type if needed. If provisioning
+     * fails, stopTethering will be called automatically.
+     *
+     * @param type The tethering type, on of the {@code TetheringManager#TETHERING_*} constants.
+     */
+    public void startTethering(int type) {
+        mTetheringManager.startTethering(type, getApplication().getMainExecutor(),
+                mStartTetheringCallback);
+    }
+
+    /**
+     * Stops tethering for the given type. Also cancels any provisioning rechecks for that type if
+     * applicable.
+     *
+     * @param type The tethering type, on of the {@code TetheringManager#TETHERING_*} constants.
+     */
+    public void stopTethering(int type) {
+        mTetheringManager.stopTethering(type);
+    }
+
     /**
      * Callback for use with {@link TetheringManager#registerTetheringEventCallback} to find out
      * tethering upstream status.
@@ -72,4 +94,16 @@ public class TetheringManagerModel extends AndroidViewModel {
             mTetheredInterfaces.setValue(interfaces);
         }
     }
+
+    private class StartTetheringCallback implements TetheringManager.StartTetheringCallback {
+        @Override
+        public void onTetheringStarted() {
+            // Do nothing
+        }
+
+        @Override
+        public void onTetheringFailed(int error) {
+            // Do nothing
+        }
+    }
 }