Refactor hotspot into a full page

- Deprecated WifiAPEnabler, and copied most of its logic into various
  controllers and WifiTetherSettings.
- Added tests

Fix: 37253404
Fix: 36181835

Test: make RunSettingsRoboTests
Change-Id: Iad994d61b694ad7f1113d045a3e7500eeaec178b

src/com/android/settings/wifi/tether/WifiTetherApBandPreferenceController.java

@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.wifi.tether;
+
+import android.content.Context;
+import android.net.wifi.WifiConfiguration;
+import android.support.v7.preference.ListPreference;
+import android.support.v7.preference.Preference;
+import android.support.v7.preference.PreferenceScreen;
+
+import com.android.settings.R;
+
+import static android.net.wifi.WifiConfiguration.AP_BAND_2GHZ;
+import static android.net.wifi.WifiConfiguration.AP_BAND_5GHZ;
+
+public class WifiTetherApBandPreferenceController extends WifiTetherBasePreferenceController {
+
+    private static final String PREF_KEY = "wifi_tether_network_ap_band";
+    private static final String[] BAND_VALUES =
+            {String.valueOf(AP_BAND_2GHZ), String.valueOf(AP_BAND_5GHZ)};
+
+    private final String[] mBandEntries;
+    private int mBandIndex;
+
+    public WifiTetherApBandPreferenceController(Context context,
+            OnTetherConfigUpdateListener listener) {
+        super(context, listener);
+        mBandEntries = mContext.getResources().getStringArray(R.array.wifi_ap_band_config_full);
+        final WifiConfiguration config = mWifiManager.getWifiApConfiguration();
+        if (config != null) {
+            mBandIndex = config.apBand;
+        } else {
+            mBandIndex = 0;
+        }
+    }
+
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        super.displayPreference(screen);
+        ListPreference preference = (ListPreference) mPreference;
+        if (!is5GhzBandSupported()) {
+            preference.setEnabled(false);
+            preference.setSummary(R.string.wifi_ap_choose_2G);
+        } else {
+            preference.setEntries(mBandEntries);
+            preference.setEntryValues(BAND_VALUES);
+            preference.setSummary(mBandEntries[mBandIndex]);
+            preference.setValue(String.valueOf(mBandIndex));
+        }
+    }
+
+    @Override
+    public String getPreferenceKey() {
+        return PREF_KEY;
+    }
+
+    @Override
+    public boolean onPreferenceChange(Preference preference, Object newValue) {
+        mBandIndex = Integer.parseInt((String) newValue);
+        preference.setSummary(mBandEntries[mBandIndex]);
+        mListener.onTetherConfigUpdated();
+        return true;
+    }
+
+    private boolean is5GhzBandSupported() {
+        if (mBandIndex > 0) {
+            return true;
+        }
+        return mWifiManager.is5GHzBandSupported();
+    }
+
+    public int getBandIndex() {
+        return mBandIndex;
+    }
+}