1 /*
2  * Copyright (C) 2018 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
5  * except in compliance with the License. You may obtain a copy of the License at
6  *
7  *      http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software distributed under the
10  * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
11  * KIND, either express or implied. See the License for the specific language governing
12  * permissions and limitations under the License.
13  */
14 package com.android.settings.display;
15 
16 import android.app.ActivityManager;
17 import android.content.ContentResolver;
18 import android.content.Context;
19 import android.database.ContentObserver;
20 import android.hardware.display.ColorDisplayManager;
21 import android.net.Uri;
22 import android.os.Handler;
23 import android.os.Looper;
24 import android.provider.Settings.Secure;
25 import android.provider.Settings.System;
26 
27 import androidx.annotation.VisibleForTesting;
28 import androidx.preference.Preference;
29 import androidx.preference.PreferenceScreen;
30 
31 import com.android.settings.R;
32 import com.android.settings.core.TogglePreferenceController;
33 import com.android.settingslib.core.lifecycle.LifecycleObserver;
34 import com.android.settingslib.core.lifecycle.events.OnStart;
35 import com.android.settingslib.core.lifecycle.events.OnStop;
36 
37 public class DisplayWhiteBalancePreferenceController extends TogglePreferenceController
38     implements LifecycleObserver, OnStart, OnStop {
39 
40     private ColorDisplayManager mColorDisplayManager;
41     @VisibleForTesting
42     ContentObserver mContentObserver;
43     private Preference mPreference;
44 
DisplayWhiteBalancePreferenceController(Context context, String key)45     public DisplayWhiteBalancePreferenceController(Context context, String key) {
46         super(context, key);
47     }
48 
49     @Override
getAvailabilityStatus()50     public int getAvailabilityStatus() {
51         return getColorDisplayManager().isDisplayWhiteBalanceAvailable(mContext) ?
52             AVAILABLE : DISABLED_FOR_USER;
53     }
54 
55     @Override
isChecked()56     public boolean isChecked() {
57         return getColorDisplayManager().isDisplayWhiteBalanceEnabled();
58     }
59 
60     @Override
setChecked(boolean isChecked)61     public boolean setChecked(boolean isChecked) {
62         return getColorDisplayManager().setDisplayWhiteBalanceEnabled(isChecked);
63     }
64 
65     @Override
getSliceHighlightMenuRes()66     public int getSliceHighlightMenuRes() {
67         return R.string.menu_key_display;
68     }
69 
70     @Override
onStart()71     public void onStart() {
72         if (!isAvailable()) {
73             return;
74         }
75 
76         final ContentResolver cr = mContext.getContentResolver();
77         mContentObserver = new ContentObserver(new Handler(Looper.getMainLooper())) {
78             @Override
79             public void onChange(boolean selfChange, Uri uri) {
80                 super.onChange(selfChange, uri);
81                 updateVisibility();
82             }
83         };
84         cr.registerContentObserver(
85                 Secure.getUriFor(Secure.ACCESSIBILITY_DISPLAY_INVERSION_ENABLED),
86                 false /* notifyForDescendants */, mContentObserver,
87                 ActivityManager.getCurrentUser());
88         cr.registerContentObserver(
89                 Secure.getUriFor(Secure.ACCESSIBILITY_DISPLAY_DALTONIZER_ENABLED),
90                 false /* notifyForDescendants */, mContentObserver,
91                 ActivityManager.getCurrentUser());
92         cr.registerContentObserver(
93                 System.getUriFor(System.DISPLAY_COLOR_MODE),
94                 false /* notifyForDescendants */, mContentObserver,
95                 ActivityManager.getCurrentUser());
96 
97         updateVisibility();
98     }
99 
100     @Override
onStop()101     public void onStop() {
102         if (mContentObserver != null) {
103             mContext.getContentResolver().unregisterContentObserver(mContentObserver);
104             mContentObserver = null;
105         }
106     }
107 
108     @Override
displayPreference(PreferenceScreen screen)109     public void displayPreference(PreferenceScreen screen) {
110         super.displayPreference(screen);
111         mPreference = screen.findPreference(getPreferenceKey());
112     }
113 
114     @VisibleForTesting
getColorDisplayManager()115     ColorDisplayManager getColorDisplayManager() {
116         if (mColorDisplayManager == null) {
117             mColorDisplayManager = mContext.getSystemService(ColorDisplayManager.class);
118         }
119         return mColorDisplayManager;
120     }
121 
122     @VisibleForTesting
updateVisibility()123     void updateVisibility() {
124         if (mPreference != null) {
125             ColorDisplayManager cdm = getColorDisplayManager();
126 
127             // Display white balance is only valid in linear light space. COLOR_MODE_SATURATED
128             // implies unmanaged color mode, and hence unknown color processing conditions.
129             // We also disallow display white balance when color accessibility features are enabled.
130             mPreference.setVisible(cdm.getColorMode() != ColorDisplayManager.COLOR_MODE_SATURATED &&
131                     !cdm.areAccessibilityTransformsEnabled(mContext));
132         }
133     }
134 }
135