Remove "Screen lock" category header as the title is sufficient.

Bug: 5203189

Insert a descriptive text as a header view when in weak biometric
fallback case.

Change-Id: Ic10cc7d276975b13c188bd15016fea2200ec0e5b

res/layout/weak_biometric_fallback_header.xml

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2011 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.
+-->
+<TextView xmlns:android="http://schemas.android.com/apk/res/android"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:padding="8dip"
+        android:gravity="center"
+        android:textAppearance="?android:attr/textAppearanceMedium"
+        android:textColor="?android:attr/textColorSecondary"
+        android:text="@string/unlock_backup_info_summary"
+/>

res/xml/security_settings_picker.xml

@@ -16,17 +16,6 @@
 
 <PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
 
-     <PreferenceCategory
-        android:key="security_picker_category"
-        android:title="@string/lock_settings_picker_title">
-
-<!-- TODO: find a better way to display this backup info -->
-        <PreferenceScreen
-            android:key="unlock_backup_info"
-            android:summary="@string/unlock_backup_info_summary"
-            android:selectable="false"
-            android:persistent="false"/>
-
     <PreferenceScreen
             android:key="unlock_set_off"
             android:title="@string/unlock_set_unlock_off_title"
@@ -63,6 +52,4 @@
             android:summary="@string/unlock_set_unlock_password_summary"
             android:persistent="false"/>
 
-    </PreferenceCategory>
-
 </PreferenceScreen>

src/com/android/settings/ChooseLockGeneric.java

@@ -25,9 +25,12 @@ import android.os.Bundle;
 import android.os.SystemProperties;
 import android.preference.Preference;
 import android.preference.PreferenceActivity;
-import android.preference.PreferenceCategory;
 import android.preference.PreferenceScreen;
 import android.security.KeyStore;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.ListView;
 
 import com.android.internal.widget.LockPatternUtils;
 
@@ -118,6 +121,21 @@ public class ChooseLockGeneric extends PreferenceActivity {
             return handled;
         }
 
+        @Override
+        public View onCreateView(LayoutInflater inflater, ViewGroup container,
+                Bundle savedInstanceState) {
+            View v = super.onCreateView(inflater, container, savedInstanceState);
+            final boolean onlyShowFallback = getActivity().getIntent()
+                    .getBooleanExtra(LockPatternUtils.LOCKSCREEN_BIOMETRIC_WEAK_FALLBACK, false);
+            if (onlyShowFallback) {
+                View header = v.inflate(getActivity(),
+                        R.layout.weak_biometric_fallback_header, null);
+                ((ListView) v.findViewById(android.R.id.list)).addHeaderView(header, null, false);
+            }
+
+            return v;
+        }
+
         @Override
         public void onActivityResult(int requestCode, int resultCode, Intent data) {
             super.onActivityResult(requestCode, resultCode, data);
@@ -205,30 +223,18 @@ public class ChooseLockGeneric extends PreferenceActivity {
          * @param quality the requested quality.
          */
         private void disableUnusablePreferences(final int quality) {
-            final Preference picker =
+            final PreferenceScreen entries = getPreferenceScreen();
-                    getPreferenceScreen().findPreference("security_picker_category");
-            final PreferenceCategory cat = (PreferenceCategory) picker;
-            final int preferenceCount = cat.getPreferenceCount();
             final boolean onlyShowFallback = getActivity().getIntent()
                     .getBooleanExtra(LockPatternUtils.LOCKSCREEN_BIOMETRIC_WEAK_FALLBACK, false);
             final boolean weakBiometricAvailable = isBiometricSensorAvailable(
                     DevicePolicyManager.PASSWORD_QUALITY_BIOMETRIC_WEAK);
-            // TODO: This code can be removed once the second header is gone
+            for (int i = entries.getPreferenceCount() - 1; i >= 0; --i) {
-            if (onlyShowFallback) {
+                Preference pref = entries.getPreference(i);
-                picker.setTitle(R.string.backup_lock_settings_picker_title);
-            } else {
-                picker.setTitle(R.string.lock_settings_picker_title);
-            }
-            for (int i = preferenceCount-1; i >= 0; --i) {
-                Preference pref = cat.getPreference(i);
                 if (pref instanceof PreferenceScreen) {
                     final String key = ((PreferenceScreen) pref).getKey();
                     boolean enabled = true;
                     boolean visible = true;
-                    if (KEY_UNLOCK_BACKUP_INFO.equals(key)) {
+                    if (KEY_UNLOCK_SET_OFF.equals(key)) {
-                        enabled = true;
-                        visible = onlyShowFallback;
-                    } else if (KEY_UNLOCK_SET_OFF.equals(key)) {
                         enabled = quality <= DevicePolicyManager.PASSWORD_QUALITY_UNSPECIFIED;
                     } else if (KEY_UNLOCK_SET_NONE.equals(key)) {
                         enabled = quality <= DevicePolicyManager.PASSWORD_QUALITY_UNSPECIFIED;
@@ -243,7 +249,7 @@ public class ChooseLockGeneric extends PreferenceActivity {
                         enabled = quality <= DevicePolicyManager.PASSWORD_QUALITY_COMPLEX;
                     }
                     if (!visible || (onlyShowFallback && !allowedForFallback(key))) {
-                        cat.removePreference(pref);
+                        entries.removePreference(pref);
                     } else if (!enabled) {
                         pref.setSummary(R.string.unlock_set_unlock_disabled_summary);
                         pref.setEnabled(false);