Merge "Improve volume slider" into main

src/com/android/settings/notification/VolumeSeekBarPreference.java

@@ -131,6 +131,11 @@ public class VolumeSeekBarPreference extends SeekBarPreference {
 
     protected void init() {
         if (mSeekBar == null) return;
+        // It's unnecessary to set up relevant volumizer configuration if preference is disabled.
+        if (!isEnabled()) {
+            mSeekBar.setEnabled(false);
+            return;
+        }
         final SeekBarVolumizer.Callback sbvc = new SeekBarVolumizer.Callback() {
             @Override
             public void onSampleStarting(SeekBarVolumizer sbv) {
@@ -179,10 +184,6 @@ public class VolumeSeekBarPreference extends SeekBarPreference {
         if (mListener != null) {
             mListener.onUpdateMuteState();
         }
-        if (!isEnabled()) {
-            mSeekBar.setEnabled(false);
-            mVolumizer.stop();
-        }
     }
 
     protected void updateIconView() {

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

@@ -81,6 +81,7 @@ public class VolumeSeekBarPreferenceTest {
 
     @Test
     public void init_listenerIsCalled() {
+        when(mPreference.isEnabled()).thenReturn(true);
         doCallRealMethod().when(mPreference).setListener(mListener);
         doCallRealMethod().when(mPreference).init();
 
@@ -92,6 +93,18 @@ public class VolumeSeekBarPreferenceTest {
 
     @Test
     public void init_listenerNotSet_noException() {
+        when(mPreference.isEnabled()).thenReturn(true);
+        doCallRealMethod().when(mPreference).init();
+
+        mPreference.init();
+
+        verify(mPreference, never()).updateContentDescription(CONTENT_DESCRIPTION);
+    }
+
+    @Test
+    public void init_preferenceIsDisabled_shouldNotInvokeListener() {
+        when(mPreference.isEnabled()).thenReturn(false);
+        doCallRealMethod().when(mPreference).setListener(mListener);
         doCallRealMethod().when(mPreference).init();
 
         mPreference.init();