Refactor ConfigureWifiSettings for better testing

Fix: 34205150
Test: make -j40 RunSettingsRoboTests
Change-Id: I7a8a0c89c087365fb50f3a9edd2cf64b2dda647c

src/com/android/settings/wifi/CellularFallbackPreferenceController.java

@@ -0,0 +1,85 @@
+/*
+ * 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;
+
+import android.content.Context;
+import android.provider.Settings;
+import android.support.v14.preference.SwitchPreference;
+import android.support.v7.preference.Preference;
+import android.text.TextUtils;
+
+import com.android.settings.core.PreferenceController;
+
+/**
+ * {@link PreferenceController} that controls whether we should fall back to celluar when wifi is
+ * bad.
+ */
+public class CellularFallbackPreferenceController extends PreferenceController {
+
+    private static final String KEY_CELLULAR_FALLBACK = "wifi_cellular_data_fallback";
+
+
+    public CellularFallbackPreferenceController(Context context) {
+        super(context);
+    }
+
+    @Override
+    public boolean isAvailable() {
+        return !avoidBadWifiConfig();
+    }
+
+    @Override
+    public String getPreferenceKey() {
+        return KEY_CELLULAR_FALLBACK;
+    }
+
+    @Override
+    public boolean handlePreferenceTreeClick(Preference preference) {
+        if (!TextUtils.equals(preference.getKey(), KEY_CELLULAR_FALLBACK)) {
+            return false;
+        }
+        if (!(preference instanceof SwitchPreference)) {
+            return false;
+        }
+        // On: avoid bad wifi. Off: prompt.
+        String settingName = Settings.Global.NETWORK_AVOID_BAD_WIFI;
+        Settings.Global.putString(mContext.getContentResolver(), settingName,
+                ((SwitchPreference) preference).isChecked() ? "1" : null);
+        return true;
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        final boolean currentSetting = avoidBadWifiCurrentSettings();
+        // TODO: can this ever be null? The return value of avoidBadWifiConfig() can only
+        // change if the resources change, but if that happens the activity will be recreated...
+        if (preference != null) {
+            SwitchPreference pref = (SwitchPreference) preference;
+            pref.setChecked(currentSetting);
+        }
+    }
+
+    private boolean avoidBadWifiConfig() {
+        return mContext.getResources().getInteger(
+                com.android.internal.R.integer.config_networkAvoidBadWifi) == 1;
+    }
+
+    private boolean avoidBadWifiCurrentSettings() {
+        return "1".equals(Settings.Global.getString(mContext.getContentResolver(),
+                Settings.Global.NETWORK_AVOID_BAD_WIFI));
+    }
+}