Add lock-to-app to settings

Lock-to-app when disabled shows some instructions about how to
enable it and use it.

When enabled shows an option of use lock screen, which controls
whether the device is locked when exiting lock-to-app.  Turning
on use lock screen requires that the device have some security
challenge.

Bug: 15759649
Change-Id: I6188243e03fb0c85bdfdbc32a23ad486296a34f9

res/layout/lock_to_app_instructions.xml

@@ -0,0 +1,74 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+/*
+** Copyright 2014, 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.
+*/
+-->
+
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent">
+
+    <LinearLayout
+        android:id="@+id/instructions_area"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:orientation="vertical"
+        android:paddingLeft="@dimen/switchbar_subsettings_margin_start"
+        android:paddingRight="@dimen/screen_margin_sides">
+
+        <TextView
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_alignParentTop="true"
+            android:paddingTop="@dimen/lock_to_app_textview_padding"
+            android:text="@string/lock_to_app_description"
+            android:textAppearance="@style/TextAppearance.Medium"
+            />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:paddingTop="@dimen/lock_to_app_textview_padding"
+            android:text="@string/lock_to_app_start_step1"
+            android:textAppearance="@style/TextAppearance.Medium"
+            />
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:paddingTop="@dimen/lock_to_app_textview_padding"
+            android:text="@string/lock_to_app_start_step2"
+            android:textAppearance="@style/TextAppearance.Medium"
+            />
+
+        <TextView
+            android:id="@+id/lock_to_app_start_step3"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:paddingBottom="@dimen/lock_to_app_textview_padding"
+            android:paddingTop="@dimen/lock_to_app_textview_padding"
+            android:text="@string/lock_to_app_start_step3"
+            android:textAppearance="@style/TextAppearance.Medium"
+            />
+
+    </LinearLayout>
+
+    <ListView
+        android:id="@android:id/list"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"/>
+
+</FrameLayout>

res/values/dimens.xml

@@ -147,4 +147,7 @@
     <dimen name="search_suggestion_item_image_margin_start">32dp</dimen>
     <dimen name="search_suggestion_item_image_margin_end">16dp</dimen>
 
+    <!-- Lock-to-app textview paddings -->
+    <dimen name="lock_to_app_textview_padding">16dp</dimen>
+
 </resources>

res/values/strings.xml

@@ -5400,4 +5400,18 @@
     <!-- Switch On/Off  -->
     <string name="switch_on_text">On</string>
     <string name="switch_off_text">Off</string>
+
+    <!-- Lock-to-app title [CHAR LIMIT=24] -->
+    <string name="lock_to_app_title">Lock-to-app</string>
+    <!-- Description of lock-to-app feature [CHAR LIMIT=105] -->
+    <string name="lock_to_app_description">Lock-to-app locks the display in a single app.\n\n\nTo start Lock-to-app</string>
+    <!-- Lock-to-app starting instruction 1. [CHAR LIMIT=45] -->
+    <string name="lock_to_app_start_step1">1\t\tTurn the setting on</string>
+    <!-- Lock-to-app starting instruction 2. [CHAR LIMIT=55] -->
+    <string name="lock_to_app_start_step2">2\t\tStart an app you want</string>
+    <!-- Lock-to-app starting instruction 3. The $ is not actually shown or
+         translated, it is a marker of where the recents icon shows up. [CHAR LIMIT=60] -->
+    <string name="lock_to_app_start_step3">3\t\tPress and hold the recent apps button $</string>
+    <!-- Label for whether should use screen lock or not. [CHAR LIMIT=30]-->
+    <string name="lock_to_app_screen_lock">Use screen lock</string>
 </resources>

res/xml/lock_to_app_settings.xml

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2014 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.
+-->
+
+<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"
+        android:title="@string/lock_to_app_title"
+        xmlns:settings="http://schemas.android.com/apk/res/com.android.settings">
+
+        <SwitchPreference
+                android:key="use_screen_lock"
+                android:title="@string/lock_to_app_screen_lock"
+                android:persistent="false" />
+
+</PreferenceScreen>

res/xml/security_settings_misc.xml

@@ -102,4 +102,10 @@
                 android:persistent="false"
                 android:fragment="com.android.settings.AdvancedSecuritySettings"/>
     </PreferenceCategory>
+
+    <PreferenceScreen
+        android:key="lock_to_app_settings"
+        android:fragment="com.android.settings.LockToAppSettings"
+        android:title="@string/lock_to_app_title"/>
+
 </PreferenceScreen>

src/com/android/settings/LockToAppSettings.java

@@ -0,0 +1,258 @@
+/*
+ * Copyright (C) 2014 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;
+
+import android.app.admin.DevicePolicyManager;
+import android.content.Context;
+import android.content.Intent;
+import android.content.res.Resources;
+import android.graphics.BitmapFactory;
+import android.os.Bundle;
+import android.preference.Preference;
+import android.preference.Preference.OnPreferenceChangeListener;
+import android.preference.PreferenceScreen;
+import android.preference.SwitchPreference;
+import android.provider.Settings;
+import android.provider.Settings.SettingNotFoundException;
+import android.text.Spannable;
+import android.text.SpannableString;
+import android.text.style.DynamicDrawableSpan;
+import android.text.style.ImageSpan;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.Switch;
+import android.widget.TextView;
+
+import com.android.internal.widget.LockPatternUtils;
+import com.android.settings.search.BaseSearchIndexProvider;
+import com.android.settings.search.Indexable;
+import com.android.settings.search.SearchIndexableRaw;
+import com.android.settings.widget.SwitchBar;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Location access settings.
+ */
+public class LockToAppSettings extends SettingsPreferenceFragment
+        implements SwitchBar.OnSwitchChangeListener, Indexable {
+    private static final String TAG = "LockToAppSettings";
+
+    private static final CharSequence KEY_USE_SCREEN_LOCK = "use_screen_lock";
+    private static final int CHANGE_LOCK_METHOD_REQUEST = 123;
+
+    private SwitchBar mSwitchBar;
+    private SwitchPreference mUseScreenLock;
+
+    @Override
+    public void onActivityCreated(Bundle savedInstanceState) {
+        super.onActivityCreated(savedInstanceState);
+
+        final SettingsActivity activity = (SettingsActivity) getActivity();
+
+        mSwitchBar = activity.getSwitchBar();
+        mSwitchBar.addOnSwitchChangeListener(this);
+        mSwitchBar.show();
+    }
+
+    @Override
+    public void onDestroyView() {
+        super.onDestroyView();
+
+        mSwitchBar.removeOnSwitchChangeListener(this);
+        mSwitchBar.hide();
+    }
+
+    @Override
+    public void onStop() {
+        super.onStop();
+    }
+
+    @Override
+    public void onResume() {
+        super.onResume();
+        if (isLockToAppEnabled()) {
+            mSwitchBar.setChecked(true);
+            createPreferenceHierarchy();
+        } else {
+            mSwitchBar.setChecked(false);
+            createSetupInstructions();
+        }
+    }
+
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container,
+            Bundle savedInstanceState) {
+        return inflater.inflate(R.layout.lock_to_app_instructions, null);
+    }
+
+    private boolean isLockToAppEnabled() {
+        try {
+            return Settings.System.getInt(getContentResolver(), Settings.System.LOCK_TO_APP_ENABLED)
+                != 0;
+        } catch (SettingNotFoundException e) {
+            return false;
+        }
+    }
+
+    private boolean isLockScreenEnabled() {
+        try {
+            return Settings.System.getInt(getContentResolver(),
+                    Settings.System.LOCK_TO_APP_EXIT_LOCKED) != 0;
+        } catch (SettingNotFoundException e) {
+            return false;
+        }
+    }
+
+    private void setLockToAppEnabled(boolean isEnabled) {
+        Settings.System.putInt(getContentResolver(), Settings.System.LOCK_TO_APP_ENABLED,
+                isEnabled ? 1 : 0);
+    }
+
+    private void setUseLockScreen(boolean useLockScreen) {
+        if (useLockScreen) {
+            LockPatternUtils lockPatternUtils = new LockPatternUtils(getActivity());
+            if (lockPatternUtils.getKeyguardStoredPasswordQuality()
+                    == DevicePolicyManager.PASSWORD_QUALITY_UNSPECIFIED) {
+                Intent chooseLockIntent = new Intent(DevicePolicyManager.ACTION_SET_NEW_PASSWORD);
+                chooseLockIntent.putExtra(
+                        ChooseLockGeneric.ChooseLockGenericFragment.MINIMUM_QUALITY_KEY,
+                        DevicePolicyManager.PASSWORD_QUALITY_SOMETHING);
+                startActivityForResult(chooseLockIntent, CHANGE_LOCK_METHOD_REQUEST);
+                return;
+            }
+        }
+        setUseLockScreenSetting(useLockScreen);
+    }
+
+    private void setUseLockScreenSetting(boolean useLockScreen) {
+        mUseScreenLock.setChecked(useLockScreen);
+        Settings.System.putInt(getContentResolver(), Settings.System.LOCK_TO_APP_EXIT_LOCKED,
+                useLockScreen ? 1 : 0);
+    }
+
+    @Override
+    public void onActivityResult(int requestCode, int resultCode, Intent data) {
+        super.onActivityResult(requestCode, resultCode, data);
+        if (requestCode == CHANGE_LOCK_METHOD_REQUEST) {
+            LockPatternUtils lockPatternUtils = new LockPatternUtils(getActivity());
+            setUseLockScreenSetting(lockPatternUtils.getKeyguardStoredPasswordQuality()
+                    != DevicePolicyManager.PASSWORD_QUALITY_UNSPECIFIED);
+        }
+    }
+
+    private PreferenceScreen createPreferenceHierarchy() {
+        PreferenceScreen root = getPreferenceScreen();
+        if (root != null) {
+            root.removeAll();
+        }
+        getView().findViewById(R.id.instructions_area).setVisibility(View.INVISIBLE);
+        addPreferencesFromResource(R.xml.lock_to_app_settings);
+        root = getPreferenceScreen();
+
+        mUseScreenLock = (SwitchPreference) root.findPreference(KEY_USE_SCREEN_LOCK);
+        mUseScreenLock.setOnPreferenceChangeListener(new OnPreferenceChangeListener() {
+            @Override
+            public boolean onPreferenceChange(Preference preference, Object newValue) {
+                setUseLockScreen((boolean) newValue);
+                return true;
+            }
+        });
+        mUseScreenLock.setChecked(isLockScreenEnabled());
+
+        return root;
+    }
+
+    private void createSetupInstructions() {
+        PreferenceScreen root = getPreferenceScreen();
+        if (root != null) {
+            root.removeAll();
+        }
+        final View view = getView();
+        view.findViewById(R.id.instructions_area).setVisibility(View.VISIBLE);
+
+        final Resources r = Resources.getSystem();
+        TextView tv = (TextView) view.findViewById(R.id.lock_to_app_start_step3);
+        ImageSpan imageSpan = new ImageSpan(getActivity(),
+                BitmapFactory.decodeResource(r, com.android.internal.R.drawable.ic_recent),
+                DynamicDrawableSpan.ALIGN_BOTTOM);
+
+        String descriptionString = getResources().getString(R.string.lock_to_app_start_step3);
+        SpannableString description =
+                new SpannableString(descriptionString.replace('$', ' '));
+        int index = descriptionString.indexOf('$');
+        if (index >= 0) {
+            description.setSpan(imageSpan, index, index + 1, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
+        }
+
+        // Make icon fit.
+        float width = imageSpan.getDrawable().getIntrinsicWidth();
+        float height = imageSpan.getDrawable().getIntrinsicHeight();
+        int lineHeight = tv.getLineHeight();
+        imageSpan.getDrawable().setBounds(0, 0, (int) (lineHeight * width / height), lineHeight);
+
+        tv.setText(description);
+    }
+
+    /**
+     * Listens to the state change of the lock-to-app master switch.
+     */
+    @Override
+    public void onSwitchChanged(Switch switchView, boolean isChecked) {
+        setLockToAppEnabled(isChecked);
+        if (isChecked) {
+            createPreferenceHierarchy();
+        } else {
+            createSetupInstructions();
+        }
+    }
+
+    /**
+     * For search
+     */
+    public static final SearchIndexProvider SEARCH_INDEX_DATA_PROVIDER =
+        new BaseSearchIndexProvider() {
+            @Override
+            public List<SearchIndexableRaw> getRawDataToIndex(Context context, boolean enabled) {
+                final List<SearchIndexableRaw> result = new ArrayList<SearchIndexableRaw>();
+
+                final Resources res = context.getResources();
+
+                // Add fragment title
+                SearchIndexableRaw data = new SearchIndexableRaw(context);
+                data.title = res.getString(R.string.lock_to_app_title);
+                data.screenTitle = res.getString(R.string.lock_to_app_title);
+                result.add(data);
+
+                // Lock-to-app description.
+                data = new SearchIndexableRaw(context);
+                data.title = res.getString(R.string.lock_to_app_description);
+                data.screenTitle = res.getString(R.string.lock_to_app_title);
+                result.add(data);
+
+                // Lock-to-app use screen lock.
+                data = new SearchIndexableRaw(context);
+                data.title = res.getString(R.string.lock_to_app_screen_lock);
+                data.screenTitle = res.getString(R.string.lock_to_app_title);
+                result.add(data);
+
+                return result;
+            }
+        };
+}

src/com/android/settings/search/Ranking.java

@@ -23,6 +23,7 @@ import com.android.settings.DevelopmentSettings;
 import com.android.settings.DeviceInfoSettings;
 import com.android.settings.DisplaySettings;
 import com.android.settings.HomeSettings;
+import com.android.settings.LockToAppSettings;
 import com.android.settings.PrivacySettings;
 import com.android.settings.SecuritySettings;
 import com.android.settings.WallpaperTypeSettings;
@@ -127,6 +128,7 @@ public final class Ranking {
         // Security
         sRankMap.put(SecuritySettings.class.getName(), RANK_SECURITY);
         sRankMap.put(ChooseLockGeneric.ChooseLockGenericFragment.class.getName(), RANK_SECURITY);
+        sRankMap.put(LockToAppSettings.class.getName(), RANK_SECURITY);
 
         // IMEs
         sRankMap.put(InputMethodAndLanguageSettings.class.getName(), RANK_IME);

src/com/android/settings/search/SearchIndexableResources.java

@@ -25,6 +25,7 @@ import com.android.settings.DevelopmentSettings;
 import com.android.settings.DeviceInfoSettings;
 import com.android.settings.DisplaySettings;
 import com.android.settings.HomeSettings;
+import com.android.settings.LockToAppSettings;
 import com.android.settings.PrivacySettings;
 import com.android.settings.R;
 import com.android.settings.SecuritySettings;
@@ -199,6 +200,13 @@ public final class SearchIndexableResources {
                         ChooseLockGeneric.ChooseLockGenericFragment.class.getName(),
                         R.drawable.ic_settings_security));
 
+        sResMap.put(LockToAppSettings.class.getName(),
+                new SearchIndexableResource(
+                        Ranking.getRankForClassName(LockToAppSettings.class.getName()),
+                        NO_DATA_RES_ID,
+                        LockToAppSettings.class.getName(),
+                        R.drawable.ic_settings_security));
+
         sResMap.put(InputMethodAndLanguageSettings.class.getName(),
                 new SearchIndexableResource(
                         Ranking.getRankForClassName(InputMethodAndLanguageSettings.class.getName()),