"Bottom padding overrides" -> EmptyStateUiHelper

As part of ongoing work to pull low-level empty state responsibilities
out of the pager adapter, this CL generally replicates the change
prototyped in ag/24516421/4..5, in smaller incremental steps to "show
the work." As originally described in that CL:

  "... moves ownership/usage of the 'container bottom padding
override supplier' over to the UI helper; this PagerAdapter dependency
is really only used in empty-state logic, so it can be handed over to
the extracted component *instead of* retaining it as an ivar in the
PagerAdapter."

As presented in this CL, the "incremental steps" per-snapshot are:

 1. Move `getActiveEmptyStateView()` from `ChooserActivity` to
    `MultiProfilePagerAdapter`, and expose it in favor of the broader
    `getEmptyStateView()` method that `ChooserActivity` previously
    used to implement the lower-level logic.

 2. Remove `MultiProfilePagerAdapter.setupContainerPadding()`
    parameters since they're just derived from a combination of a
    single hard-coded (resource) symbol, and a concern that already
    belonged to the pager-adapter (`getActiveEmptyStateView()`).
    Switch tests to using one of our real layouts so that we can find
    an empty-state container with the expected View ID.

    Also update method visibility to show `setupContainerPadding()`
    isn't intended to be overridden in the more-modern "generic pager"
    design, and update Javadoc accordingly.

 3. Inline `ChooserMultiProfilePagerAdapter.setupContainerPadding()`
    as part of its `setEmptyStateBottomOffset()`, since the latter
    method is never called anywhere else (and both concerns already
    belonged to the specialized pager-adapter).

 4. Refactor the internal `setupContainerPadding()` to operate on
    profile descriptors instead of container Views. This is based on
    the observation that both callers of `setupContainerPadding()`
    were passing containers that they had to query from the
    descriptor's empty-state view anyways, and the lookup used the
    same View ID in both cases. This change encapsulates those shared
    concerns at a higher level of abstraction.

 5. Move the implementation logic of `setupContainerPadding()` into
    the descriptor inner-class; given the override-supplier, the rest
    of the operation can be implemented just using the info available
    to the descriptor.

 6. Move ownership of the override-supplier into the descriptor (to be
    shared among all descriptor instances). The outer pager-adapter
    had no remaining need to reference the supplier, and we can easily
    confirm that this results in `setupContainerPadding()` calls for
    each descriptor instance using the same supplier instance they
    would've used before.

 7. Moves implementation logic (including [shared] ownership of the
    override-supplier) from the descriptor down to the empty-state
    helper which now encapsulates the entire `setupContainerPadding()`
    operation with zero args.

    This may require *slightly* more of a leap-of-faith than the other
    "steps," but note the extensive test coverage: the existing
    `MultiProfilePagerAdapterTest` covers this exact functionality
    as integrated into a broader config; parallel unit tests are
    newly-added in `EmptyStateUiHelper`; and even our "broad-scope"
    integration tests exercise empty-state logic to _some_ degree.

 8. Inlines some client usages to simplify scaffolding that we don't
    really need after the earlier refactoring changes.

Bug: 302311217
Test: IntentResolverUnitTests
Change-Id: Icc460ede5b8a0314d5c807dd884e6e2b7044bee9

6 files changed, 110 insertions, 54 deletions

diff --git a/java/src/com/android/intentresolver/v2/ChooserActivity.java b/java/src/com/android/intentresolver/v2/ChooserActivity.java
index a755b9e9..9a8b0e2a 100644
--- a/java/src/com/android/intentresolver/v2/ChooserActivity.java
+++ b/java/src/com/android/intentresolver/v2/ChooserActivity.java
@@ -1473,7 +1473,8 @@ public class ChooserActivity extends Hilt_ChooserActivity implements
                 rowsToShow--;
             }
         } else {
-            ViewGroup currentEmptyStateView = getActiveEmptyStateView();
+            ViewGroup currentEmptyStateView =
+                    mChooserMultiProfilePagerAdapter.getActiveEmptyStateView();
             if (currentEmptyStateView.getVisibility() == View.VISIBLE) {
                 offset += currentEmptyStateView.getHeight();
             }
@@ -1507,11 +1508,6 @@ public class ChooserActivity extends Hilt_ChooserActivity implements
         return PROFILE_PERSONAL;
     }
 
-    private ViewGroup getActiveEmptyStateView() {
-        int currentPage = mChooserMultiProfilePagerAdapter.getCurrentPage();
-        return mChooserMultiProfilePagerAdapter.getEmptyStateView(currentPage);
-    }
-
     @Override // ResolverListCommunicator
     public void onHandlePackagesChanged(ResolverListAdapter listAdapter) {
         mChooserMultiProfilePagerAdapter.getActiveListAdapter().notifyDataSetChanged();
@@ -1782,8 +1778,6 @@ public class ChooserActivity extends Hilt_ChooserActivity implements
         if (shouldShowTabs()) {
             mChooserMultiProfilePagerAdapter
                     .setEmptyStateBottomOffset(insets.getSystemWindowInsetBottom());
-            mChooserMultiProfilePagerAdapter.setupContainerPadding(
-                    getActiveEmptyStateView().findViewById(com.android.internal.R.id.resolver_empty_state_container));
         }
 
         WindowInsets result = super.onApplyWindowInsets(v, insets);
diff --git a/java/src/com/android/intentresolver/v2/ChooserMultiProfilePagerAdapter.java b/java/src/com/android/intentresolver/v2/ChooserMultiProfilePagerAdapter.java
index d3c9efea..8ca976bc 100644
--- a/java/src/com/android/intentresolver/v2/ChooserMultiProfilePagerAdapter.java
+++ b/java/src/com/android/intentresolver/v2/ChooserMultiProfilePagerAdapter.java
@@ -128,6 +128,7 @@ public class ChooserMultiProfilePagerAdapter extends MultiProfilePagerAdapter<
 
     public void setEmptyStateBottomOffset(int bottomOffset) {
         mBottomPaddingOverrideSupplier.setEmptyStateBottomOffset(bottomOffset);
+        setupContainerPadding();
     }
 
     /**
diff --git a/java/src/com/android/intentresolver/v2/MultiProfilePagerAdapter.java b/java/src/com/android/intentresolver/v2/MultiProfilePagerAdapter.java
index b2a167e1..ad9614b9 100644
--- a/java/src/com/android/intentresolver/v2/MultiProfilePagerAdapter.java
+++ b/java/src/com/android/intentresolver/v2/MultiProfilePagerAdapter.java
@@ -89,7 +89,6 @@ public class MultiProfilePagerAdapter<
     private final Function<SinglePageAdapterT, ListAdapterT> mListAdapterExtractor;
     private final AdapterBinder<PageViewT, SinglePageAdapterT> mAdapterBinder;
     private final Supplier<ViewGroup> mPageViewInflater;
-    private final Supplier<Optional<Integer>> mContainerBottomPaddingOverrideSupplier;
 
     private final ImmutableList<ProfileDescriptor<PageViewT, SinglePageAdapterT>> mItems;
 
@@ -123,19 +122,20 @@ public class MultiProfilePagerAdapter<
         mListAdapterExtractor = listAdapterExtractor;
         mAdapterBinder = adapterBinder;
         mPageViewInflater = pageViewInflater;
-        mContainerBottomPaddingOverrideSupplier = containerBottomPaddingOverrideSupplier;
 
         ImmutableList.Builder<ProfileDescriptor<PageViewT, SinglePageAdapterT>> items =
                 new ImmutableList.Builder<>();
         for (SinglePageAdapterT adapter : adapters) {
-            items.add(createProfileDescriptor(adapter));
+            items.add(createProfileDescriptor(adapter, containerBottomPaddingOverrideSupplier));
         }
         mItems = items.build();
     }
 
     private ProfileDescriptor<PageViewT, SinglePageAdapterT> createProfileDescriptor(
-            SinglePageAdapterT adapter) {
-        return new ProfileDescriptor<>(mPageViewInflater.get(), adapter);
+            SinglePageAdapterT adapter,
+            Supplier<Optional<Integer>> containerBottomPaddingOverrideSupplier) {
+        return new ProfileDescriptor<>(
+                mPageViewInflater.get(), adapter, containerBottomPaddingOverrideSupplier);
     }
 
     public void setOnProfileSelectedListener(OnProfileSelectedListener listener) {
@@ -235,10 +235,14 @@ public class MultiProfilePagerAdapter<
         return mItems.get(pageIndex);
     }
 
-    public ViewGroup getEmptyStateView(int pageIndex) {
+    private ViewGroup getEmptyStateView(int pageIndex) {
         return getItem(pageIndex).getEmptyStateView();
     }
 
+    public ViewGroup getActiveEmptyStateView() {
+        return getEmptyStateView(getCurrentPage());
+    }
+
     /**
      * Returns the number of {@link ProfileDescriptor} objects.
      * <p>For a normal consumer device with only one user returns <code>1</code>.
@@ -454,12 +458,10 @@ public class MultiProfilePagerAdapter<
         descriptor.mRootView.findViewById(
                 com.android.internal.R.id.resolver_list).setVisibility(View.GONE);
         descriptor.mEmptyStateUi.resetViewVisibilities();
+        descriptor.setupContainerPadding();
 
         ViewGroup emptyStateView = descriptor.getEmptyStateView();
 
-        View container = emptyStateView.findViewById(
-                com.android.internal.R.id.resolver_empty_state_container);
-        setupContainerPadding(container);
 
         TextView titleView = emptyStateView.findViewById(
                 com.android.internal.R.id.resolver_empty_state_title);
@@ -493,17 +495,11 @@ public class MultiProfilePagerAdapter<
     }
 
     /**
-     * Sets up the padding of the view containing the empty state screens.
-     * <p>This method is meant to be overridden so that subclasses can customize the padding.
+     * Sets up the padding of the view containing the empty state screens for the current adapter
+     * view.
      */
-    public void setupContainerPadding(View container) {
-        Optional<Integer> bottomPaddingOverride = mContainerBottomPaddingOverrideSupplier.get();
-        bottomPaddingOverride.ifPresent(paddingBottom ->
-                container.setPadding(
-                    container.getPaddingLeft(),
-                    container.getPaddingTop(),
-                    container.getPaddingRight(),
-                    paddingBottom));
+    protected final void setupContainerPadding() {
+        getItem(getCurrentPage()).setupContainerPadding();
     }
 
     public void showListView(ListAdapterT activeListAdapter) {
@@ -534,17 +530,25 @@ public class MultiProfilePagerAdapter<
         private final SinglePageAdapterT mAdapter;
         private final PageViewT mView;
 
-        ProfileDescriptor(ViewGroup rootView, SinglePageAdapterT adapter) {
+        ProfileDescriptor(
+                ViewGroup rootView,
+                SinglePageAdapterT adapter,
+                Supplier<Optional<Integer>> containerBottomPaddingOverrideSupplier) {
             mRootView = rootView;
             mAdapter = adapter;
             mEmptyStateView = rootView.findViewById(com.android.internal.R.id.resolver_empty_state);
             mView = (PageViewT) rootView.findViewById(com.android.internal.R.id.resolver_list);
-            mEmptyStateUi = new EmptyStateUiHelper(rootView);
+            mEmptyStateUi =
+                    new EmptyStateUiHelper(rootView, containerBottomPaddingOverrideSupplier);
         }
 
         protected ViewGroup getEmptyStateView() {
             return mEmptyStateView;
         }
+
+        private void setupContainerPadding() {
+            mEmptyStateUi.setupContainerPadding();
+        }
     }
 
     /** Listener interface for changes between the per-profile UI tabs. */
diff --git a/java/src/com/android/intentresolver/v2/emptystate/EmptyStateUiHelper.java b/java/src/com/android/intentresolver/v2/emptystate/EmptyStateUiHelper.java
index 7230b042..fc852f5c 100644
--- a/java/src/com/android/intentresolver/v2/emptystate/EmptyStateUiHelper.java
+++ b/java/src/com/android/intentresolver/v2/emptystate/EmptyStateUiHelper.java
@@ -18,16 +18,36 @@ package com.android.intentresolver.v2.emptystate;
 import android.view.View;
 import android.view.ViewGroup;
 
+import java.util.Optional;
+import java.util.function.Supplier;
+
 /**
  * Helper for building `MultiProfilePagerAdapter` tab UIs for profile tabs that are "blocked" by
  * some empty-state status.
  */
 public class EmptyStateUiHelper {
     private final View mEmptyStateView;
+    private final Supplier<Optional<Integer>> mContainerBottomPaddingOverrideSupplier;
 
-    public EmptyStateUiHelper(ViewGroup rootView) {
+    public EmptyStateUiHelper(
+            ViewGroup rootView,
+            Supplier<Optional<Integer>> containerBottomPaddingOverrideSupplier) {
         mEmptyStateView =
                 rootView.requireViewById(com.android.internal.R.id.resolver_empty_state);
+        mContainerBottomPaddingOverrideSupplier = containerBottomPaddingOverrideSupplier;
+    }
+
+    /** Sets up the padding of the view containing the empty state screens. */
+    public void setupContainerPadding() {
+        View container = mEmptyStateView.requireViewById(
+                com.android.internal.R.id.resolver_empty_state_container);
+        Optional<Integer> bottomPaddingOverride = mContainerBottomPaddingOverrideSupplier.get();
+        bottomPaddingOverride.ifPresent(paddingBottom ->
+                container.setPadding(
+                    container.getPaddingLeft(),
+                    container.getPaddingTop(),
+                    container.getPaddingRight(),
+                    paddingBottom));
     }
 
     public void resetViewVisibilities() {
diff --git a/java/tests/src/com/android/intentresolver/v2/MultiProfilePagerAdapterTest.kt b/java/tests/src/com/android/intentresolver/v2/MultiProfilePagerAdapterTest.kt
index f1af9790..f5dc0935 100644
--- a/java/tests/src/com/android/intentresolver/v2/MultiProfilePagerAdapterTest.kt
+++ b/java/tests/src/com/android/intentresolver/v2/MultiProfilePagerAdapterTest.kt
@@ -26,7 +26,6 @@ import com.android.intentresolver.MultiProfilePagerAdapter.PROFILE_PERSONAL
 import com.android.intentresolver.MultiProfilePagerAdapter.PROFILE_WORK
 import com.android.intentresolver.R
 import com.android.intentresolver.ResolverListAdapter
-import com.android.intentresolver.any
 import com.android.intentresolver.emptystate.EmptyStateProvider
 import com.android.intentresolver.mock
 import com.android.intentresolver.whenever
@@ -35,8 +34,6 @@ import com.google.common.truth.Truth.assertThat
 import java.util.Optional
 import java.util.function.Supplier
 import org.junit.Test
-import org.mockito.Mockito.never
-import org.mockito.Mockito.verify
 
 class MultiProfilePagerAdapterTest {
     private val PERSONAL_USER_HANDLE = UserHandle.of(10)
@@ -158,20 +155,15 @@ class MultiProfilePagerAdapterTest {
 
     @Test
     fun testBottomPaddingDelegate_default() {
-        val container =
-            mock<View> {
-                whenever(getPaddingLeft()).thenReturn(1)
-                whenever(getPaddingTop()).thenReturn(2)
-                whenever(getPaddingRight()).thenReturn(3)
-                whenever(getPaddingBottom()).thenReturn(4)
-            }
+        val personalListAdapter =
+            mock<ResolverListAdapter> { whenever(getUserHandle()).thenReturn(PERSONAL_USER_HANDLE) }
         val pagerAdapter =
             MultiProfilePagerAdapter(
                 { listAdapter: ResolverListAdapter -> listAdapter },
                 { listView: ListView, bindAdapter: ResolverListAdapter ->
                     listView.setAdapter(bindAdapter)
                 },
-                ImmutableList.of(),
+                ImmutableList.of(personalListAdapter),
                 object : EmptyStateProvider {},
                 { false },
                 PROFILE_PERSONAL,
@@ -180,26 +172,29 @@ class MultiProfilePagerAdapterTest {
                 inflater,
                 { Optional.empty() }
             )
-        pagerAdapter.setupContainerPadding(container)
-        verify(container, never()).setPadding(any(), any(), any(), any())
+        val container =
+            pagerAdapter
+                .getActiveEmptyStateView()
+                .requireViewById<View>(com.android.internal.R.id.resolver_empty_state_container)
+        container.setPadding(1, 2, 3, 4)
+        pagerAdapter.setupContainerPadding()
+        assertThat(container.paddingLeft).isEqualTo(1)
+        assertThat(container.paddingTop).isEqualTo(2)
+        assertThat(container.paddingRight).isEqualTo(3)
+        assertThat(container.paddingBottom).isEqualTo(4)
     }
 
     @Test
     fun testBottomPaddingDelegate_override() {
-        val container =
-            mock<View> {
-                whenever(getPaddingLeft()).thenReturn(1)
-                whenever(getPaddingTop()).thenReturn(2)
-                whenever(getPaddingRight()).thenReturn(3)
-                whenever(getPaddingBottom()).thenReturn(4)
-            }
+        val personalListAdapter =
+            mock<ResolverListAdapter> { whenever(getUserHandle()).thenReturn(PERSONAL_USER_HANDLE) }
         val pagerAdapter =
             MultiProfilePagerAdapter(
                 { listAdapter: ResolverListAdapter -> listAdapter },
                 { listView: ListView, bindAdapter: ResolverListAdapter ->
                     listView.setAdapter(bindAdapter)
                 },
-                ImmutableList.of(),
+                ImmutableList.of(personalListAdapter),
                 object : EmptyStateProvider {},
                 { false },
                 PROFILE_PERSONAL,
@@ -208,8 +203,16 @@ class MultiProfilePagerAdapterTest {
                 inflater,
                 { Optional.of(42) }
             )
-        pagerAdapter.setupContainerPadding(container)
-        verify(container).setPadding(1, 2, 3, 42)
+        val container =
+            pagerAdapter
+                .getActiveEmptyStateView()
+                .requireViewById<View>(com.android.internal.R.id.resolver_empty_state_container)
+        container.setPadding(1, 2, 3, 4)
+        pagerAdapter.setupContainerPadding()
+        assertThat(container.paddingLeft).isEqualTo(1)
+        assertThat(container.paddingTop).isEqualTo(2)
+        assertThat(container.paddingRight).isEqualTo(3)
+        assertThat(container.paddingBottom).isEqualTo(42)
     }
 
     @Test
diff --git a/java/tests/src/com/android/intentresolver/v2/emptystate/EmptyStateUiHelperTest.kt b/java/tests/src/com/android/intentresolver/v2/emptystate/EmptyStateUiHelperTest.kt
index 12943cd7..27ed7e38 100644
--- a/java/tests/src/com/android/intentresolver/v2/emptystate/EmptyStateUiHelperTest.kt
+++ b/java/tests/src/com/android/intentresolver/v2/emptystate/EmptyStateUiHelperTest.kt
@@ -22,12 +22,20 @@ import android.view.ViewGroup
 import android.widget.FrameLayout
 import androidx.test.platform.app.InstrumentationRegistry
 import com.google.common.truth.Truth.assertThat
+import java.util.Optional
+import java.util.function.Supplier
 import org.junit.Before
 import org.junit.Test
 
 class EmptyStateUiHelperTest {
     private val context = InstrumentationRegistry.getInstrumentation().getContext()
 
+    var shouldOverrideContainerPadding = false
+    val containerPaddingSupplier =
+        Supplier<Optional<Int>> {
+            Optional.ofNullable(if (shouldOverrideContainerPadding) 42 else null)
+        }
+
     lateinit var rootContainer: ViewGroup
     lateinit var emptyStateTitleView: View
     lateinit var emptyStateSubtitleView: View
@@ -60,7 +68,7 @@ class EmptyStateUiHelperTest {
         emptyStateDefaultTextView = rootContainer.requireViewById(com.android.internal.R.id.empty)
         emptyStateContainerView =
             rootContainer.requireViewById(com.android.internal.R.id.resolver_empty_state_container)
-        emptyStateUiHelper = EmptyStateUiHelper(rootContainer)
+        emptyStateUiHelper = EmptyStateUiHelper(rootContainer, containerPaddingSupplier)
     }
 
     @Test
@@ -109,4 +117,30 @@ class EmptyStateUiHelperTest {
 
         assertThat(emptyStateRootView.visibility).isEqualTo(View.GONE)
     }
+
+    @Test
+    fun testBottomPaddingDelegate_default() {
+        shouldOverrideContainerPadding = false
+        emptyStateContainerView.setPadding(1, 2, 3, 4)
+
+        emptyStateUiHelper.setupContainerPadding()
+
+        assertThat(emptyStateContainerView.paddingLeft).isEqualTo(1)
+        assertThat(emptyStateContainerView.paddingTop).isEqualTo(2)
+        assertThat(emptyStateContainerView.paddingRight).isEqualTo(3)
+        assertThat(emptyStateContainerView.paddingBottom).isEqualTo(4)
+    }
+
+    @Test
+    fun testBottomPaddingDelegate_override() {
+        shouldOverrideContainerPadding = true // Set bottom padding to 42.
+        emptyStateContainerView.setPadding(1, 2, 3, 4)
+
+        emptyStateUiHelper.setupContainerPadding()
+
+        assertThat(emptyStateContainerView.paddingLeft).isEqualTo(1)
+        assertThat(emptyStateContainerView.paddingTop).isEqualTo(2)
+        assertThat(emptyStateContainerView.paddingRight).isEqualTo(3)
+        assertThat(emptyStateContainerView.paddingBottom).isEqualTo(42)
+    }
 }