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      1 /*
      2  * Copyright (C) 2012 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package com.android.internal.view;
     18 
     19 import android.content.Context;
     20 import android.database.ContentObserver;
     21 import android.net.Uri;
     22 import android.os.AsyncTask;
     23 import android.os.Handler;
     24 import android.os.RemoteException;
     25 import android.os.ServiceManager;
     26 import android.os.UserHandle;
     27 import android.provider.Settings;
     28 import android.util.Log;
     29 import android.view.IWindowManager;
     30 import android.view.Surface;
     31 import android.view.WindowManagerGlobal;
     32 
     33 /**
     34  * Provides helper functions for configuring the display rotation policy.
     35  */
     36 public final class RotationPolicy {
     37     private static final String TAG = "RotationPolicy";
     38 
     39     private RotationPolicy() {
     40     }
     41 
     42     /**
     43      * Returns true if the device supports the rotation-lock toggle feature
     44      * in the system UI or system bar.
     45      *
     46      * When the rotation-lock toggle is supported, the "auto-rotate screen" option in
     47      * Display settings should be hidden, but it should remain available in Accessibility
     48      * settings.
     49      */
     50     public static boolean isRotationLockToggleSupported(Context context) {
     51         return context.getResources().getConfiguration().smallestScreenWidthDp >= 600;
     52     }
     53 
     54     /**
     55      * Returns true if the rotation-lock toggle should be shown in the UI.
     56      */
     57     public static boolean isRotationLockToggleVisible(Context context) {
     58         return isRotationLockToggleSupported(context) &&
     59                 Settings.System.getIntForUser(context.getContentResolver(),
     60                         Settings.System.HIDE_ROTATION_LOCK_TOGGLE_FOR_ACCESSIBILITY, 0,
     61                         UserHandle.USER_CURRENT) == 0;
     62     }
     63 
     64     /**
     65      * Returns true if rotation lock is enabled.
     66      */
     67     public static boolean isRotationLocked(Context context) {
     68         return Settings.System.getIntForUser(context.getContentResolver(),
     69                 Settings.System.ACCELEROMETER_ROTATION, 0, UserHandle.USER_CURRENT) == 0;
     70     }
     71 
     72     /**
     73      * Enables or disables rotation lock.
     74      *
     75      * Should be used by the rotation lock toggle.
     76      */
     77     public static void setRotationLock(Context context, final boolean enabled) {
     78         Settings.System.putIntForUser(context.getContentResolver(),
     79                 Settings.System.HIDE_ROTATION_LOCK_TOGGLE_FOR_ACCESSIBILITY, 0,
     80                 UserHandle.USER_CURRENT);
     81 
     82         AsyncTask.execute(new Runnable() {
     83             @Override
     84             public void run() {
     85                 try {
     86                     IWindowManager wm = WindowManagerGlobal.getWindowManagerService();
     87                     if (enabled) {
     88                         wm.freezeRotation(-1);
     89                     } else {
     90                         wm.thawRotation();
     91                     }
     92                 } catch (RemoteException exc) {
     93                     Log.w(TAG, "Unable to save auto-rotate setting");
     94                 }
     95             }
     96         });
     97     }
     98 
     99     /**
    100      * Enables or disables rotation lock and adjusts whether the rotation lock toggle
    101      * should be hidden for accessibility purposes.
    102      *
    103      * Should be used by Display settings and Accessibility settings.
    104      */
    105     public static void setRotationLockForAccessibility(Context context, final boolean enabled) {
    106         Settings.System.putIntForUser(context.getContentResolver(),
    107                 Settings.System.HIDE_ROTATION_LOCK_TOGGLE_FOR_ACCESSIBILITY, enabled ? 1 : 0,
    108                         UserHandle.USER_CURRENT);
    109 
    110         AsyncTask.execute(new Runnable() {
    111             @Override
    112             public void run() {
    113                 try {
    114                     IWindowManager wm = WindowManagerGlobal.getWindowManagerService();
    115                     if (enabled) {
    116                         wm.freezeRotation(Surface.ROTATION_0);
    117                     } else {
    118                         wm.thawRotation();
    119                     }
    120                 } catch (RemoteException exc) {
    121                     Log.w(TAG, "Unable to save auto-rotate setting");
    122                 }
    123             }
    124         });
    125     }
    126 
    127     /**
    128      * Registers a listener for rotation policy changes affecting the caller's user
    129      */
    130     public static void registerRotationPolicyListener(Context context,
    131             RotationPolicyListener listener) {
    132         registerRotationPolicyListener(context, listener, UserHandle.getCallingUserId());
    133     }
    134 
    135     /**
    136      * Registers a listener for rotation policy changes affecting a specific user,
    137      * or USER_ALL for all users.
    138      */
    139     public static void registerRotationPolicyListener(Context context,
    140             RotationPolicyListener listener, int userHandle) {
    141         context.getContentResolver().registerContentObserver(Settings.System.getUriFor(
    142                 Settings.System.ACCELEROMETER_ROTATION),
    143                 false, listener.mObserver, userHandle);
    144         context.getContentResolver().registerContentObserver(Settings.System.getUriFor(
    145                 Settings.System.HIDE_ROTATION_LOCK_TOGGLE_FOR_ACCESSIBILITY),
    146                 false, listener.mObserver, userHandle);
    147     }
    148 
    149     /**
    150      * Unregisters a listener for rotation policy changes.
    151      */
    152     public static void unregisterRotationPolicyListener(Context context,
    153             RotationPolicyListener listener) {
    154         context.getContentResolver().unregisterContentObserver(listener.mObserver);
    155     }
    156 
    157     /**
    158      * Listener that is invoked whenever a change occurs that might affect the rotation policy.
    159      */
    160     public static abstract class RotationPolicyListener {
    161         final ContentObserver mObserver = new ContentObserver(new Handler()) {
    162             public void onChange(boolean selfChange, Uri uri) {
    163                 RotationPolicyListener.this.onChange();
    164             }
    165         };
    166 
    167         public abstract void onChange();
    168     }
    169 }