Fix the a11y focus problem in a long list page

While a page is scrolling to the target position, the target can't
request a11y focus, and the highlight blink animation at the moment is
also invisible.

The patch is to skip the unseen highlight animation and focus operation
when onBindViewHolder() is called before scrolling. Therefore, when the
scrolling stops, the scroll listener will notify the item changed and
onBindViewHolder() will be called again to do the operations.

Also decrease the delay time of the scrolling start to make the a11y
smoother.

Bug: 318459003
Test: manual, robotest
Change-Id: Ie55b2edeb7e1feaaadb5e670f39f07f6f17b92b9

src/com/android/settings/widget/HighlightablePreferenceGroupAdapter.java

@@ -40,6 +40,7 @@ import androidx.recyclerview.widget.RecyclerView.ViewHolder;
 
 import com.android.settings.R;
 import com.android.settings.SettingsPreferenceFragment;
+import com.android.settings.accessibility.AccessibilityUtil;
 
 import com.google.android.material.appbar.AppBarLayout;
 
@@ -50,6 +51,8 @@ public class HighlightablePreferenceGroupAdapter extends PreferenceGroupAdapter
     static final long DELAY_COLLAPSE_DURATION_MILLIS = 300L;
     @VisibleForTesting
     static final long DELAY_HIGHLIGHT_DURATION_MILLIS = 600L;
+    @VisibleForTesting
+    static final long DELAY_HIGHLIGHT_DURATION_MILLIS_A11Y = 300L;
     private static final long HIGHLIGHT_DURATION = 15000L;
     private static final long HIGHLIGHT_FADE_OUT_DURATION = 500L;
     private static final long HIGHLIGHT_FADE_IN_DURATION = 200L;
@@ -59,6 +62,7 @@ public class HighlightablePreferenceGroupAdapter extends PreferenceGroupAdapter
     @VisibleForTesting
     boolean mFadeInAnimated;
 
+    private final Context mContext;
     private final int mNormalBackgroundRes;
     private final String mHighlightKey;
     private boolean mHighlightRequested;
@@ -102,12 +106,12 @@ public class HighlightablePreferenceGroupAdapter extends PreferenceGroupAdapter
         super(preferenceGroup);
         mHighlightKey = key;
         mHighlightRequested = highlightRequested;
-        final Context context = preferenceGroup.getContext();
+        mContext = preferenceGroup.getContext();
         final TypedValue outValue = new TypedValue();
-        context.getTheme().resolveAttribute(android.R.attr.selectableItemBackground,
+        mContext.getTheme().resolveAttribute(android.R.attr.selectableItemBackground,
                 outValue, true /* resolveRefs */);
         mNormalBackgroundRes = outValue.resourceId;
-        mHighlightColor = context.getColor(R.color.preference_highlight_color);
+        mHighlightColor = mContext.getColor(R.color.preference_highlight_color);
     }
 
     @Override
@@ -121,12 +125,11 @@ public class HighlightablePreferenceGroupAdapter extends PreferenceGroupAdapter
         View v = holder.itemView;
         if (position == mHighlightPosition
                 && (mHighlightKey != null
-                && TextUtils.equals(mHighlightKey, getItem(position).getKey()))) {
+                && TextUtils.equals(mHighlightKey, getItem(position).getKey()))
+                && v.isShown()) {
             // This position should be highlighted. If it's highlighted before - skip animation.
+            v.requestAccessibilityFocus();
             addHighlightBackground(holder, !mFadeInAnimated);
-            if (v != null) {
-                v.requestAccessibilityFocus();
-            }
         } else if (Boolean.TRUE.equals(v.getTag(R.id.preference_highlighted))) {
             // View with highlight is reused for a view that should not have highlight
             removeHighlightBackground(holder, false /* animate */);
@@ -157,13 +160,14 @@ public class HighlightablePreferenceGroupAdapter extends PreferenceGroupAdapter
 
         // Remove the animator as early as possible to avoid a RecyclerView crash.
         recyclerView.setItemAnimator(null);
-        // Scroll to correct position after 600 milliseconds.
+        // Scroll to correct position after a short delay.
         root.postDelayed(() -> {
             if (ensureHighlightPosition()) {
                 recyclerView.smoothScrollToPosition(mHighlightPosition);
                 highlightAndFocusTargetItem(recyclerView, mHighlightPosition);
             }
-        }, DELAY_HIGHLIGHT_DURATION_MILLIS);
+        }, AccessibilityUtil.isTouchExploreEnabled(mContext)
+                ? DELAY_HIGHLIGHT_DURATION_MILLIS_A11Y : DELAY_HIGHLIGHT_DURATION_MILLIS);
     }
 
     private void highlightAndFocusTargetItem(RecyclerView recyclerView, int highlightPosition) {

tests/robotests/src/com/android/settings/widget/HighlightablePreferenceGroupAdapterTest.java

@@ -33,6 +33,7 @@ import android.content.Context;
 import android.graphics.drawable.ColorDrawable;
 import android.os.Bundle;
 import android.view.View;
+import android.view.accessibility.AccessibilityManager;
 
 import androidx.preference.Preference;
 import androidx.preference.PreferenceCategory;
@@ -54,6 +55,8 @@ import org.mockito.MockitoAnnotations;
 import org.robolectric.RobolectricTestRunner;
 import org.robolectric.RuntimeEnvironment;
 import org.robolectric.annotation.Config;
+import org.robolectric.shadow.api.Shadow;
+import org.robolectric.shadows.ShadowAccessibilityManager;
 import org.robolectric.util.ReflectionHelpers;
 
 @RunWith(RobolectricTestRunner.class)
@@ -67,7 +70,7 @@ public class HighlightablePreferenceGroupAdapterTest {
     @Mock
     private View mRoot;
     @Mock
-    private PreferenceCategory mPreferenceCatetory;
+    private PreferenceCategory mPreferenceCategory;
     @Mock
     private SettingsPreferenceFragment mFragment;
 
@@ -82,8 +85,8 @@ public class HighlightablePreferenceGroupAdapterTest {
         mContext = RuntimeEnvironment.application;
         mPreference = new Preference(mContext);
         mPreference.setKey(TEST_KEY);
-        when(mPreferenceCatetory.getContext()).thenReturn(mContext);
+        when(mPreferenceCategory.getContext()).thenReturn(mContext);
-        mAdapter = spy(new HighlightablePreferenceGroupAdapter(mPreferenceCatetory, TEST_KEY,
+        mAdapter = spy(new HighlightablePreferenceGroupAdapter(mPreferenceCategory, TEST_KEY,
                 false /* highlighted*/));
         when(mAdapter.getItem(anyInt())).thenReturn(mPreference);
         mViewHolder = PreferenceViewHolder.createInstanceForTests(
@@ -101,6 +104,18 @@ public class HighlightablePreferenceGroupAdapterTest {
                 eq(HighlightablePreferenceGroupAdapter.DELAY_HIGHLIGHT_DURATION_MILLIS));
     }
 
+    @Test
+    public void requestHighlight_enableTouchExploration_shouldHaveA11yHighlightDelay() {
+        ShadowAccessibilityManager am = Shadow.extract(AccessibilityManager.getInstance(mContext));
+        am.setTouchExplorationEnabled(true);
+        when(mAdapter.getPreferenceAdapterPosition(anyString())).thenReturn(1);
+        mAdapter.requestHighlight(mRoot, mock(RecyclerView.class), mock(AppBarLayout.class));
+
+        // DELAY_HIGHLIGHT_DURATION_MILLIS_A11Y = DELAY_COLLAPSE_DURATION_MILLIS
+        verify(mRoot, times(2)).postDelayed(any(),
+                eq(HighlightablePreferenceGroupAdapter.DELAY_HIGHLIGHT_DURATION_MILLIS_A11Y));
+    }
+
     @Test
     public void requestHighlight_noKey_highlightedBefore_noRecyclerView_shouldNotRequest() {
         ReflectionHelpers.setField(mAdapter, "mHighlightKey", null);
@@ -178,12 +193,24 @@ public class HighlightablePreferenceGroupAdapterTest {
         assertThat(mViewHolder.itemView.getTag(R.id.preference_highlighted)).isNull();
     }
 
+    @Test
+    public void updateBackground_itemViewIsInvisible_shouldNotSetHighlightedTag() {
+        ReflectionHelpers.setField(mAdapter, "mHighlightPosition", 10);
+        ReflectionHelpers.setField(mViewHolder, "itemView", spy(mViewHolder.itemView));
+        when(mViewHolder.itemView.isShown()).thenReturn(false);
+
+        mAdapter.updateBackground(mViewHolder, 0);
+
+        assertThat(mViewHolder.itemView.getTag(R.id.preference_highlighted)).isNull();
+    }
+
     /**
      * When background is being updated, we also request the a11y focus on the preference
      */
     @Test
     public void updateBackground_shouldRequestAccessibilityFocus() {
         View viewItem = mock(View.class);
+        when(viewItem.isShown()).thenReturn(true);
         mViewHolder = PreferenceViewHolder.createInstanceForTests(viewItem);
         ReflectionHelpers.setField(mAdapter, "mHighlightPosition", 10);
 
@@ -195,6 +222,8 @@ public class HighlightablePreferenceGroupAdapterTest {
     @Test
     public void updateBackground_highlight_shouldAnimateBackgroundAndSetHighlightedTag() {
         ReflectionHelpers.setField(mAdapter, "mHighlightPosition", 10);
+        ReflectionHelpers.setField(mViewHolder, "itemView", spy(mViewHolder.itemView));
+        when(mViewHolder.itemView.isShown()).thenReturn(true);
         assertThat(mAdapter.mFadeInAnimated).isFalse();
 
         mAdapter.updateBackground(mViewHolder, 10);
@@ -205,10 +234,22 @@ public class HighlightablePreferenceGroupAdapterTest {
         verify(mAdapter).requestRemoveHighlightDelayed(mViewHolder);
     }
 
+    @Test
+    public void updateBackground_highlight_itemViewIsInvisible_shouldNotAnimate() {
+        ReflectionHelpers.setField(mAdapter, "mHighlightPosition", 10);
+        ReflectionHelpers.setField(mViewHolder, "itemView", spy(mViewHolder.itemView));
+        when(mViewHolder.itemView.isShown()).thenReturn(false);
+
+        mAdapter.updateBackground(mViewHolder, 10);
+
+        assertThat(mAdapter.mFadeInAnimated).isFalse();
+    }
+
     @Test
     public void updateBackgroundTwice_highlight_shouldAnimateOnce() {
         ReflectionHelpers.setField(mAdapter, "mHighlightPosition", 10);
         ReflectionHelpers.setField(mViewHolder, "itemView", spy(mViewHolder.itemView));
+        when(mViewHolder.itemView.isShown()).thenReturn(true);
         assertThat(mAdapter.mFadeInAnimated).isFalse();
         mAdapter.updateBackground(mViewHolder, 10);
         // mFadeInAnimated change from false to true - indicating background change is scheduled