Add content description to volume title in settings.

Adds content description that is announced by talkback when a11y focus
is on volume preference. This improves talkback announcement when view changes.

Fixes: 285529113
Bug: 285455826
Fixes: 285487766
Test: atest VolumeSeekBarPreferenceControllerTest
Test: atest VolumeSeekBarPreferenceTest
Change-Id: Ibe80b4b1d489dc058df1cc79c96b034d5ddc6e56

tests/robotests/src/com/android/settings/notification/VolumeSeekBarPreferenceControllerTest.java

@@ -49,6 +49,8 @@ public class VolumeSeekBarPreferenceControllerTest {
     @Mock
     private VolumeSeekBarPreference.Callback mCallback;
     @Mock
+    private VolumeSeekBarPreference.Listener mListener;
+    @Mock
     private AudioHelper mHelper;
 
     private VolumeSeekBarPreferenceControllerTestable mController;
@@ -59,7 +61,7 @@ public class VolumeSeekBarPreferenceControllerTest {
         when(mScreen.findPreference(nullable(String.class))).thenReturn(mPreference);
         when(mPreference.getKey()).thenReturn("key");
         mController = new VolumeSeekBarPreferenceControllerTestable(mContext, mCallback, true,
-                mPreference.getKey());
+                mPreference.getKey(), mListener);
         mController.setAudioHelper(mHelper);
     }
 
@@ -70,18 +72,20 @@ public class VolumeSeekBarPreferenceControllerTest {
         verify(mPreference).setCallback(mCallback);
         verify(mPreference).setStream(VolumeSeekBarPreferenceControllerTestable.AUDIO_STREAM);
         verify(mPreference).setMuteIcon(VolumeSeekBarPreferenceControllerTestable.MUTE_ICON);
+        verify(mPreference).setListener(mListener);
     }
 
     @Test
     public void displayPreference_notAvailable_shouldNotUpdatePreference() {
         mController = new VolumeSeekBarPreferenceControllerTestable(mContext, mCallback, false,
-                mPreference.getKey());
+                mPreference.getKey(), mListener);
 
         mController.displayPreference(mScreen);
 
         verify(mPreference, never()).setCallback(any(VolumeSeekBarPreference.Callback.class));
         verify(mPreference, never()).setStream(anyInt());
         verify(mPreference, never()).setMuteIcon(anyInt());
+        verify(mPreference, never()).setListener(mListener);
     }
 
     @Test
@@ -157,10 +161,12 @@ public class VolumeSeekBarPreferenceControllerTest {
         private boolean mAvailable;
 
         VolumeSeekBarPreferenceControllerTestable(Context context,
-            VolumeSeekBarPreference.Callback callback, boolean available, String key) {
+                VolumeSeekBarPreference.Callback callback, boolean available, String key,
+                VolumeSeekBarPreference.Listener listener) {
             super(context, key);
             setCallback(callback);
             mAvailable = available;
+            mVolumePreferenceListener = listener;
         }
 
         @Override

tests/robotests/src/com/android/settings/notification/VolumeSeekBarPreferenceTest.java

@@ -18,11 +18,14 @@ package com.android.settings.notification;
 
 import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.Mockito.doCallRealMethod;
+import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
 import android.content.Context;
 import android.media.AudioManager;
+import android.preference.SeekBarVolumizer;
+import android.widget.SeekBar;
 
 import org.junit.Before;
 import org.junit.Test;
@@ -34,18 +37,28 @@ import org.robolectric.RobolectricTestRunner;
 @RunWith(RobolectricTestRunner.class)
 public class VolumeSeekBarPreferenceTest {
 
+    private static final CharSequence CONTENT_DESCRIPTION = "TEST";
     @Mock
     private AudioManager mAudioManager;
     @Mock
     private VolumeSeekBarPreference mPreference;
     @Mock
     private Context mContext;
+    @Mock
+    private SeekBar mSeekBar;
+    @Mock
+    private SeekBarVolumizer mVolumizer;
+    private VolumeSeekBarPreference.Listener mListener;
 
     @Before
     public void setUp() {
         MockitoAnnotations.initMocks(this);
         when(mContext.getSystemService(Context.AUDIO_SERVICE)).thenReturn(mAudioManager);
+        doCallRealMethod().when(mPreference).updateContentDescription(CONTENT_DESCRIPTION);
+        mPreference.mSeekBar = mSeekBar;
         mPreference.mAudioManager = mAudioManager;
+        mPreference.mVolumizer = mVolumizer;
+        mListener = () -> mPreference.updateContentDescription(CONTENT_DESCRIPTION);
     }
 
     @Test
@@ -65,4 +78,24 @@ public class VolumeSeekBarPreferenceTest {
         verify(mPreference).setMin(min);
         verify(mPreference).setProgress(progress);
     }
+
+    @Test
+    public void init_listenerIsCalled() {
+        doCallRealMethod().when(mPreference).setListener(mListener);
+        doCallRealMethod().when(mPreference).init();
+
+        mPreference.setListener(mListener);
+        mPreference.init();
+
+        verify(mPreference).updateContentDescription(CONTENT_DESCRIPTION);
+    }
+
+    @Test
+    public void init_listenerNotSet_noException() {
+        doCallRealMethod().when(mPreference).init();
+
+        mPreference.init();
+
+        verify(mPreference, never()).updateContentDescription(CONTENT_DESCRIPTION);
+    }
 }