Add mono audio to AccessibilitySettings

Bug: 15283594
Change-Id: If5ca14a800e1932b17ef479589beb8a5d1489b5d

res/values/strings.xml

@@ -3868,6 +3868,10 @@
     <string name="accessibility_toggle_speak_password_preference_title">Speak passwords</string>
     <!-- Title for the accessibility preference for enabling/disabling large icons for mouse/trackpad pointers. [CHAR LIMIT=35] -->
     <string name="accessibility_toggle_large_pointer_icon_title">Large mouse pointer</string>
+    <!-- Title for the accessibility preference for master mono. [CHAR LIMIT=35] -->
+    <string name="accessibility_toggle_master_mono_title">Mono audio</string>
+    <!-- Summary for the accessibility preference for master mono. [CHAR LIMIT=50] -->
+    <string name="accessibility_toggle_master_mono_summary">Combine channels when playing audio</string>
     <!-- Title for accessibility preference to choose long-press delay i.e. timeout before it is detected. [CHAR LIMIT=35] -->
     <string name="accessibility_long_press_timeout_preference_title">Tap &amp; hold delay</string>
     <!-- Title for the accessibility preference to configure display color inversion. [CHAR LIMIT=NONE] -->

res/xml/accessibility_settings.xml

@@ -76,6 +76,12 @@
                 android:key="toggle_large_pointer_icon"
                 android:title="@string/accessibility_toggle_large_pointer_icon_title" />
 
+        <SwitchPreference
+                android:key="toggle_master_mono"
+                android:title="@string/accessibility_toggle_master_mono_title"
+                android:summary="@string/accessibility_toggle_master_mono_summary"
+                android:persistent="false"/>
+
         <PreferenceScreen
                 android:fragment="com.android.settings.accessibility.ToggleGlobalGesturePreferenceFragment"
                 android:key="enable_global_gesture_preference_screen"

src/com/android/settings/accessibility/AccessibilitySettings.java

@@ -86,6 +86,8 @@ public class AccessibilitySettings extends SettingsPreferenceFragment implements
             "toggle_speak_password_preference";
     private static final String TOGGLE_LARGE_POINTER_ICON =
             "toggle_large_pointer_icon";
+    private static final String TOGGLE_MASTER_MONO =
+            "toggle_master_mono";
     private static final String SELECT_LONG_PRESS_TIMEOUT_PREFERENCE =
             "select_long_press_timeout_preference";
     private static final String ENABLE_ACCESSIBILITY_GESTURE_PREFERENCE_SCREEN =
@@ -182,6 +184,7 @@ public class AccessibilitySettings extends SettingsPreferenceFragment implements
     private SwitchPreference mToggleLockScreenRotationPreference;
     private SwitchPreference mToggleSpeakPasswordPreference;
     private SwitchPreference mToggleLargePointerIconPreference;
+    private SwitchPreference mToggleMasterMonoPreference;
     private ListPreference mSelectLongPressTimeoutPreference;
     private Preference mNoServicesMessagePreference;
     private PreferenceScreen mCaptioningPreferenceScreen;
@@ -280,6 +283,9 @@ public class AccessibilitySettings extends SettingsPreferenceFragment implements
         } else if (mToggleLargePointerIconPreference == preference) {
             handleToggleLargePointerIconPreferenceClick();
             return true;
+        } else if (mToggleMasterMonoPreference == preference) {
+            handleToggleMasterMonoPreferenceClick();
+            return true;
         } else if (mGlobalGesturePreferenceScreen == preference) {
             handleToggleEnableAccessibilityGesturePreferenceClick();
             return true;
@@ -321,6 +327,11 @@ public class AccessibilitySettings extends SettingsPreferenceFragment implements
                 mToggleLargePointerIconPreference.isChecked() ? 1 : 0);
     }
 
+    private void handleToggleMasterMonoPreferenceClick() {
+        Settings.System.putIntForUser(getContentResolver(), Settings.System.MASTER_MONO,
+                mToggleMasterMonoPreference.isChecked() ? 1 : 0, UserHandle.USER_CURRENT);
+    }
+
     private void handleToggleEnableAccessibilityGesturePreferenceClick() {
         Bundle extras = mGlobalGesturePreferenceScreen.getExtras();
         extras.putString(EXTRA_TITLE, getString(
@@ -378,6 +389,10 @@ public class AccessibilitySettings extends SettingsPreferenceFragment implements
         mToggleLargePointerIconPreference =
                 (SwitchPreference) findPreference(TOGGLE_LARGE_POINTER_ICON);
 
+        // Master Mono
+        mToggleMasterMonoPreference =
+                (SwitchPreference) findPreference(TOGGLE_MASTER_MONO);
+
         // Long press timeout.
         mSelectLongPressTimeoutPreference =
                 (ListPreference) findPreference(SELECT_LONG_PRESS_TIMEOUT_PREFERENCE);
@@ -571,6 +586,9 @@ public class AccessibilitySettings extends SettingsPreferenceFragment implements
         mToggleLargePointerIconPreference.setChecked(Settings.Secure.getInt(getContentResolver(),
                 Settings.Secure.ACCESSIBILITY_LARGE_POINTER_ICON, 0) != 0);
 
+        // Master mono
+        updateMasterMono();
+
         // Long press timeout.
         final int longPressTimeout = Settings.Secure.getInt(getContentResolver(),
                 Settings.Secure.LONG_PRESS_TIMEOUT, mLongPressTimeoutDefault);
@@ -640,6 +658,13 @@ public class AccessibilitySettings extends SettingsPreferenceFragment implements
         }
     }
 
+    private void updateMasterMono() {
+        final boolean masterMono = Settings.System.getIntForUser(
+                getContentResolver(), Settings.System.MASTER_MONO,
+                0 /* default */, UserHandle.USER_CURRENT) == 1;
+        mToggleMasterMonoPreference.setChecked(masterMono);
+    }
+
     public static final SearchIndexProvider SEARCH_INDEX_DATA_PROVIDER =
             new BaseSearchIndexProvider() {
         @Override