Refactor IMEAndLanguageSettings to use PreferenceController

Bug: 32642706
Bug: 32637613
Bug: 32643833
Test: RunSettingsRoboTests

This change is necessary to test preference controlling logic, as well
as making preferences reusable in other Preference pages in the new
information architecture.

Change-Id: I9e2fd2f6800579f005a5c303ed03ae06477006a6

src/com/android/settings/inputmethod/SpellCheckerPreferenceController.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2016 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.inputmethod;
+
+import android.content.Context;
+import android.support.v7.preference.Preference;
+import android.support.v7.preference.PreferenceScreen;
+import android.view.textservice.SpellCheckerInfo;
+import android.view.textservice.TextServicesManager;
+
+import com.android.settings.R;
+import com.android.settings.core.PreferenceController;
+
+public class SpellCheckerPreferenceController extends PreferenceController {
+
+    public static final String KEY_SPELL_CHECKERS = "spellcheckers_settings";
+
+    private final TextServicesManager mTextServicesManager;
+
+    public SpellCheckerPreferenceController(Context context) {
+        super(context);
+        mTextServicesManager = (TextServicesManager) context.getSystemService(
+                Context.TEXT_SERVICES_MANAGER_SERVICE);
+    }
+
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        super.displayPreference(screen);
+        final Preference preference = screen.findPreference(KEY_SPELL_CHECKERS);
+        if (preference != null) {
+            InputMethodAndSubtypeUtil.removeUnnecessaryNonPersistentPreference(preference);
+        }
+    }
+
+    @Override
+    public boolean isAvailable() {
+        return true;
+    }
+
+    @Override
+    public boolean handlePreferenceTreeClick(Preference preference) {
+        return false;
+    }
+
+    @Override
+    public String getPreferenceKey() {
+        return KEY_SPELL_CHECKERS;
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        if (preference == null) {
+            return;
+        }
+        if (!mTextServicesManager.isSpellCheckerEnabled()) {
+            preference.setSummary(R.string.switch_off_text);
+        } else {
+            final SpellCheckerInfo sci = mTextServicesManager.getCurrentSpellChecker();
+            if (sci != null) {
+                preference.setSummary(sci.loadLabel(mContext.getPackageManager()));
+            } else {
+                preference.setSummary(R.string.spell_checker_not_selected);
+            }
+        }
+    }
+}