Expand SplitContainer if min dimensions not satisfied

Before this CL, SplitController creates new SplitContainer if min dimensions of new lauched Activity/Intent is not satisfied. This CL changes to expand the existing SplitContainer Bug: 232871351 Test: atest SplitPresenterTest Change-Id: Id8d122f7d95d1c6a3574b02ddd2b6afbc548f853
2022-06-13 18:24:35 +08:00
parent d9fa425f92
commit bd2723cf6e
5 changed files with 287 additions and 46 deletions
--- a/libs/WindowManager/Jetpack/src/androidx/window/extensions/embedding/SplitController.java
+++ b/libs/WindowManager/Jetpack/src/androidx/window/extensions/embedding/SplitController.java
@@ -24,9 +24,9 @@ import static androidx.window.extensions.embedding.SplitContainer.getFinishSecon
 import static androidx.window.extensions.embedding.SplitContainer.isStickyPlaceholderRule;
 import static androidx.window.extensions.embedding.SplitContainer.shouldFinishAssociatedContainerWhenAdjacent;
 import static androidx.window.extensions.embedding.SplitContainer.shouldFinishAssociatedContainerWhenStacked;
-import static androidx.window.extensions.embedding.SplitPresenter.boundsSmallerThanMinDimensions;
+import static androidx.window.extensions.embedding.SplitPresenter.RESULT_EXPAND_FAILED_NO_TF_INFO;
 import static androidx.window.extensions.embedding.SplitPresenter.getActivityIntentMinDimensionsPair;
-import static androidx.window.extensions.embedding.SplitPresenter.getMinDimensions;
+import static androidx.window.extensions.embedding.SplitPresenter.getNonEmbeddedActivityBounds;
 import static androidx.window.extensions.embedding.SplitPresenter.shouldShowSideBySide;

 import android.app.Activity;
@@ -381,6 +381,7 @@ public class SplitController implements JetpackTaskFragmentOrganizer.TaskFragmen
     *         in a state that the caller shouldn't handle.
     */
    @VisibleForTesting
+    @GuardedBy("mLock")
    boolean resolveActivityToContainer(@NonNull Activity activity, boolean isOnReparent) {
        if (isInPictureInPicture(activity) || activity.isFinishing()) {
            // We don't embed activity when it is in PIP, or finishing. Return true since we don't
@@ -581,8 +582,9 @@ public class SplitController implements JetpackTaskFragmentOrganizer.TaskFragmen
    }

    /** Finds the activity below the given activity. */
+    @VisibleForTesting
    @Nullable
-    private Activity findActivityBelow(@NonNull Activity activity) {
+    Activity findActivityBelow(@NonNull Activity activity) {
        Activity activityBelow = null;
        final TaskFragmentContainer container = getContainerWithActivity(activity);
        if (container != null) {
@@ -606,6 +608,7 @@ public class SplitController implements JetpackTaskFragmentOrganizer.TaskFragmen
     * Checks if there is a rule to split the two activities. If there is one, puts them into split
     * and returns {@code true}. Otherwise, returns {@code false}.
     */
+    @GuardedBy("mLock")
    private boolean putActivitiesIntoSplitIfNecessary(@NonNull Activity primaryActivity,
            @NonNull Activity secondaryActivity) {
        final SplitPairRule splitRule = getSplitRule(primaryActivity, secondaryActivity);
@@ -616,25 +619,25 @@ public class SplitController implements JetpackTaskFragmentOrganizer.TaskFragmen
                primaryActivity);
        final SplitContainer splitContainer = getActiveSplitForContainer(primaryContainer);
        if (splitContainer != null && primaryContainer == splitContainer.getPrimaryContainer()
-                && canReuseContainer(splitRule, splitContainer.getSplitRule())
-                && !boundsSmallerThanMinDimensions(primaryContainer.getLastRequestedBounds(),
-                        getMinDimensions(primaryActivity))) {
+                && canReuseContainer(splitRule, splitContainer.getSplitRule())) {
            // Can launch in the existing secondary container if the rules share the same
            // presentation.
            final TaskFragmentContainer secondaryContainer = splitContainer.getSecondaryContainer();
-            if (secondaryContainer == getContainerWithActivity(secondaryActivity)
-                    && !boundsSmallerThanMinDimensions(secondaryContainer.getLastRequestedBounds(),
-                            getMinDimensions(secondaryActivity))) {
+            if (secondaryContainer == getContainerWithActivity(secondaryActivity)) {
                // The activity is already in the target TaskFragment.
                return true;
            }
            secondaryContainer.addPendingAppearedActivity(secondaryActivity);
            final WindowContainerTransaction wct = new WindowContainerTransaction();
-            wct.reparentActivityToTaskFragment(
-                    secondaryContainer.getTaskFragmentToken(),
-                    secondaryActivity.getActivityToken());
-            mPresenter.applyTransaction(wct);
-            return true;
+            if (mPresenter.expandSplitContainerIfNeeded(wct, splitContainer, primaryActivity,
+                    secondaryActivity, null /* secondaryIntent */)
+                    != RESULT_EXPAND_FAILED_NO_TF_INFO) {
+                wct.reparentActivityToTaskFragment(
+                        secondaryContainer.getTaskFragmentToken(),
+                        secondaryActivity.getActivityToken());
+                mPresenter.applyTransaction(wct);
+                return true;
+            }
        }
        // Create new split pair.
        mPresenter.createNewSplitContainer(primaryActivity, secondaryActivity, splitRule);
@@ -787,6 +790,7 @@ public class SplitController implements JetpackTaskFragmentOrganizer.TaskFragmen
     * Returns a container for the new activity intent to launch into as splitting with the primary
     * activity.
     */
+    @GuardedBy("mLock")
    @Nullable
    private TaskFragmentContainer getSecondaryContainerForSplitIfAny(
            @NonNull WindowContainerTransaction wct, @NonNull Activity primaryActivity,
@@ -800,16 +804,12 @@ public class SplitController implements JetpackTaskFragmentOrganizer.TaskFragmen
        if (splitContainer != null && existingContainer == splitContainer.getPrimaryContainer()
                && (canReuseContainer(splitRule, splitContainer.getSplitRule())
                // TODO(b/231845476) we should always respect clearTop.
-                || !respectClearTop)) {
-            final Rect secondaryBounds = splitContainer.getSecondaryContainer()
-                    .getLastRequestedBounds();
-            if (secondaryBounds.isEmpty()
-                    || !boundsSmallerThanMinDimensions(secondaryBounds,
-                            getMinDimensions(intent))) {
-                // Can launch in the existing secondary container if the rules share the same
-                // presentation.
-                return splitContainer.getSecondaryContainer();
-            }
+                || !respectClearTop)
+                && mPresenter.expandSplitContainerIfNeeded(wct, splitContainer, primaryActivity,
+                        null /* secondaryActivity */, intent) != RESULT_EXPAND_FAILED_NO_TF_INFO) {
+            // Can launch in the existing secondary container if the rules share the same
+            // presentation.
+            return splitContainer.getSecondaryContainer();
        }
        // Create a new TaskFragment to split with the primary activity for the new activity.
        return mPresenter.createNewSplitWithEmptySideContainer(wct, primaryActivity, intent,
@@ -863,6 +863,7 @@ public class SplitController implements JetpackTaskFragmentOrganizer.TaskFragmen
     *                                  if needed.
     * @param taskId                    parent Task of the new TaskFragment.
     */
+    @GuardedBy("mLock")
    TaskFragmentContainer newContainer(@Nullable Activity pendingAppearedActivity,
            @Nullable Intent pendingAppearedIntent, @NonNull Activity activityInTask, int taskId) {
        if (activityInTask == null) {
@@ -876,7 +877,7 @@ public class SplitController implements JetpackTaskFragmentOrganizer.TaskFragmen
                pendingAppearedIntent, taskContainer, this);
        if (!taskContainer.isTaskBoundsInitialized()) {
            // Get the initial bounds before the TaskFragment has appeared.
-            final Rect taskBounds = SplitPresenter.getTaskBoundsFromActivity(activityInTask);
+            final Rect taskBounds = getNonEmbeddedActivityBounds(activityInTask);
            if (!taskContainer.setTaskBounds(taskBounds)) {
                Log.w(TAG, "Can't find bounds from activity=" + activityInTask);
            }
--- a/libs/WindowManager/Jetpack/src/androidx/window/extensions/embedding/SplitPresenter.java
+++ b/libs/WindowManager/Jetpack/src/androidx/window/extensions/embedding/SplitPresenter.java
@@ -65,6 +65,41 @@ class SplitPresenter extends JetpackTaskFragmentOrganizer {
    })
    private @interface Position {}

+    /**
+     * Result of {@link #expandSplitContainerIfNeeded(WindowContainerTransaction, SplitContainer,
+     * Activity, Activity, Intent)}.
+     * No need to expand the splitContainer because screen is big enough to
+     * {@link #shouldShowSideBySide(Rect, SplitRule, Pair)} and minimum dimensions is satisfied.
+     */
+    static final int RESULT_NOT_EXPANDED = 0;
+    /**
+     * Result of {@link #expandSplitContainerIfNeeded(WindowContainerTransaction, SplitContainer,
+     * Activity, Activity, Intent)}.
+     * The splitContainer should be expanded. It is usually because minimum dimensions is not
+     * satisfied.
+     * @see #shouldShowSideBySide(Rect, SplitRule, Pair)
+     */
+    static final int RESULT_EXPANDED = 1;
+    /**
+     * Result of {@link #expandSplitContainerIfNeeded(WindowContainerTransaction, SplitContainer,
+     * Activity, Activity, Intent)}.
+     * The splitContainer should be expanded, but the client side hasn't received
+     * {@link android.window.TaskFragmentInfo} yet. Fallback to create new expanded SplitContainer
+     * instead.
+     */
+    static final int RESULT_EXPAND_FAILED_NO_TF_INFO = 2;
+
+    /**
+     * Result of {@link #expandSplitContainerIfNeeded(WindowContainerTransaction, SplitContainer,
+     * Activity, Activity, Intent)}
+     */
+    @IntDef(value = {
+            RESULT_NOT_EXPANDED,
+            RESULT_EXPANDED,
+            RESULT_EXPAND_FAILED_NO_TF_INFO,
+    })
+    private @interface ResultCode {}
+
    private final SplitController mController;

    SplitPresenter(@NonNull Executor executor, SplitController controller) {
@@ -396,6 +431,44 @@ class SplitPresenter extends JetpackTaskFragmentOrganizer {
        super.updateWindowingMode(wct, fragmentToken, windowingMode);
    }

+    /**
+     * Expands the split container if the current split bounds are smaller than the Activity or
+     * Intent that is added to the container.
+     *
+     * @return the {@link ResultCode} based on {@link #shouldShowSideBySide(Rect, SplitRule, Pair)}
+     * and if {@link android.window.TaskFragmentInfo} has reported to the client side.
+     */
+    @ResultCode
+    int expandSplitContainerIfNeeded(@NonNull WindowContainerTransaction wct,
+            @NonNull SplitContainer splitContainer, @NonNull Activity primaryActivity,
+            @Nullable Activity secondaryActivity, @Nullable Intent secondaryIntent) {
+        if (secondaryActivity == null && secondaryIntent == null) {
+            throw new IllegalArgumentException("Either secondaryActivity or secondaryIntent must be"
+                    + " non-null.");
+        }
+        final Rect taskBounds = getParentContainerBounds(primaryActivity);
+        final Pair<Size, Size> minDimensionsPair;
+        if (secondaryActivity != null) {
+            minDimensionsPair = getActivitiesMinDimensionsPair(primaryActivity, secondaryActivity);
+        } else {
+            minDimensionsPair = getActivityIntentMinDimensionsPair(primaryActivity,
+                    secondaryIntent);
+        }
+        // Expand the splitContainer if minimum dimensions are not satisfied.
+        if (!shouldShowSideBySide(taskBounds, splitContainer.getSplitRule(), minDimensionsPair)) {
+            // If the client side hasn't received TaskFragmentInfo yet, we can't change TaskFragment
+            // bounds. Return failure to create a new SplitContainer which fills task bounds.
+            if (splitContainer.getPrimaryContainer().getInfo() == null
+                    || splitContainer.getSecondaryContainer().getInfo() == null) {
+                return RESULT_EXPAND_FAILED_NO_TF_INFO;
+            }
+            expandTaskFragment(wct, splitContainer.getPrimaryContainer().getTaskFragmentToken());
+            expandTaskFragment(wct, splitContainer.getSecondaryContainer().getTaskFragmentToken());
+            return RESULT_EXPANDED;
+        }
+        return RESULT_NOT_EXPANDED;
+    }
+
    static boolean shouldShowSideBySide(@NonNull Rect parentBounds, @NonNull SplitRule rule) {
        return shouldShowSideBySide(parentBounds, rule, null /* minimumDimensionPair */);
    }
@@ -565,11 +638,19 @@ class SplitPresenter extends JetpackTaskFragmentOrganizer {
        if (container != null) {
            return getParentContainerBounds(container);
        }
-        return getTaskBoundsFromActivity(activity);
+        // Obtain bounds from Activity instead because the Activity hasn't been embedded yet.
+        return getNonEmbeddedActivityBounds(activity);
    }

+    /**
+     * Obtains the bounds from a non-embedded Activity.
+     * <p>
+     * Note that callers should use {@link #getParentContainerBounds(Activity)} instead for most
+     * cases unless we want to obtain task bounds before
+     * {@link TaskContainer#isTaskBoundsInitialized()}.
+     */
    @NonNull
-    static Rect getTaskBoundsFromActivity(@NonNull Activity activity) {
+    static Rect getNonEmbeddedActivityBounds(@NonNull Activity activity) {
        final WindowConfiguration windowConfiguration =
                activity.getResources().getConfiguration().windowConfiguration;
        if (!activity.isInMultiWindowMode()) {
--- a/libs/WindowManager/Jetpack/tests/unittest/src/androidx/window/extensions/embedding/EmbeddingTestUtils.java
+++ b/libs/WindowManager/Jetpack/tests/unittest/src/androidx/window/extensions/embedding/EmbeddingTestUtils.java
@@ -24,6 +24,7 @@ import static org.mockito.Mockito.mock;
 import android.annotation.NonNull;
 import android.app.Activity;
 import android.content.Intent;
+import android.content.pm.ActivityInfo;
 import android.content.res.Configuration;
 import android.graphics.Point;
 import android.graphics.Rect;
@@ -57,13 +58,21 @@ public class EmbeddingTestUtils {
    /** Creates a rule to always split the given activity and the given intent. */
    static SplitRule createSplitRule(@NonNull Activity primaryActivity,
            @NonNull Intent secondaryIntent) {
+        return createSplitRule(primaryActivity, secondaryIntent, true /* clearTop */);
+    }
+
+    /** Creates a rule to always split the given activity and the given intent. */
+    static SplitRule createSplitRule(@NonNull Activity primaryActivity,
+            @NonNull Intent secondaryIntent, boolean clearTop) {
        final Pair<Activity, Intent> targetPair = new Pair<>(primaryActivity, secondaryIntent);
        return new SplitPairRule.Builder(
                activityPair -> false,
                targetPair::equals,
                w -> true)
                .setSplitRatio(SPLIT_RATIO)
-                .setShouldClearTop(true)
+                .setShouldClearTop(clearTop)
+                .setFinishPrimaryWithSecondary(DEFAULT_FINISH_PRIMARY_WITH_SECONDARY)
+                .setFinishSecondaryWithPrimary(DEFAULT_FINISH_SECONDARY_WITH_PRIMARY)
                .build();
    }

@@ -75,6 +84,14 @@ public class EmbeddingTestUtils {
                true /* clearTop */);
    }

+    /** Creates a rule to always split the given activities. */
+    static SplitRule createSplitRule(@NonNull Activity primaryActivity,
+            @NonNull Activity secondaryActivity, boolean clearTop) {
+        return createSplitRule(primaryActivity, secondaryActivity,
+                DEFAULT_FINISH_PRIMARY_WITH_SECONDARY, DEFAULT_FINISH_SECONDARY_WITH_PRIMARY,
+                clearTop);
+    }
+
    /** Creates a rule to always split the given activities with the given finish behaviors. */
    static SplitRule createSplitRule(@NonNull Activity primaryActivity,
            @NonNull Activity secondaryActivity, int finishPrimaryWithSecondary,
@@ -105,4 +122,12 @@ public class EmbeddingTestUtils {
                false /* isTaskFragmentClearedForPip */,
                new Point());
    }
+
+    static ActivityInfo createActivityInfoWithMinDimensions() {
+        ActivityInfo aInfo = new ActivityInfo();
+        final Rect primaryBounds = getSplitBounds(true /* isPrimary */);
+        aInfo.windowLayout = new ActivityInfo.WindowLayout(0, 0, 0, 0, 0,
+                primaryBounds.width() + 1, primaryBounds.height() + 1);
+        return aInfo;
+    }
 }
--- a/libs/WindowManager/Jetpack/tests/unittest/src/androidx/window/extensions/embedding/SplitControllerTest.java
+++ b/libs/WindowManager/Jetpack/tests/unittest/src/androidx/window/extensions/embedding/SplitControllerTest.java
@@ -22,6 +22,7 @@ import static android.app.WindowConfiguration.WINDOWING_MODE_UNDEFINED;
 import static androidx.window.extensions.embedding.EmbeddingTestUtils.SPLIT_RATIO;
 import static androidx.window.extensions.embedding.EmbeddingTestUtils.TASK_BOUNDS;
 import static androidx.window.extensions.embedding.EmbeddingTestUtils.TASK_ID;
+import static androidx.window.extensions.embedding.EmbeddingTestUtils.createActivityInfoWithMinDimensions;
 import static androidx.window.extensions.embedding.EmbeddingTestUtils.createMockTaskFragmentInfo;
 import static androidx.window.extensions.embedding.EmbeddingTestUtils.createSplitRule;
 import static androidx.window.extensions.embedding.EmbeddingTestUtils.getSplitBounds;
@@ -34,6 +35,7 @@ import static com.google.common.truth.Truth.assertWithMessage;

 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertThrows;
@@ -435,6 +437,50 @@ public class SplitControllerTest {
        assertTrue(container.areLastRequestedBoundsEqual(null));
    }

+    @Test
+    public void testResolveStartActivityIntent_shouldExpandSplitContainer() {
+        final Intent intent = new Intent().setComponent(
+                new ComponentName(ApplicationProvider.getApplicationContext(),
+                        MinimumDimensionActivity.class));
+        setupSplitRule(mActivity, intent, false /* clearTop */);
+        final Activity secondaryActivity = createMockActivity();
+        addSplitTaskFragments(mActivity, secondaryActivity, false /* clearTop */);
+
+        final TaskFragmentContainer container = mSplitController.resolveStartActivityIntent(
+                mTransaction, TASK_ID, intent, mActivity);
+        final TaskFragmentContainer primaryContainer = mSplitController.getContainerWithActivity(
+                mActivity);
+
+        assertNotNull(mSplitController.getActiveSplitForContainers(primaryContainer, container));
+        assertTrue(primaryContainer.areLastRequestedBoundsEqual(null));
+        assertTrue(container.areLastRequestedBoundsEqual(null));
+        assertEquals(container, mSplitController.getContainerWithActivity(secondaryActivity));
+    }
+
+    @Test
+    public void testResolveStartActivityIntent_noInfo_shouldCreateSplitContainer() {
+        final Intent intent = new Intent().setComponent(
+                new ComponentName(ApplicationProvider.getApplicationContext(),
+                        MinimumDimensionActivity.class));
+        setupSplitRule(mActivity, intent, false /* clearTop */);
+        final Activity secondaryActivity = createMockActivity();
+        addSplitTaskFragments(mActivity, secondaryActivity, false /* clearTop */);
+
+        final TaskFragmentContainer secondaryContainer = mSplitController
+                .getContainerWithActivity(secondaryActivity);
+        secondaryContainer.mInfo = null;
+
+        final TaskFragmentContainer container = mSplitController.resolveStartActivityIntent(
+                mTransaction, TASK_ID, intent, mActivity);
+        final TaskFragmentContainer primaryContainer = mSplitController.getContainerWithActivity(
+                mActivity);
+
+        assertNotNull(mSplitController.getActiveSplitForContainers(primaryContainer, container));
+        assertTrue(primaryContainer.areLastRequestedBoundsEqual(null));
+        assertTrue(container.areLastRequestedBoundsEqual(null));
+        assertNotEquals(container, secondaryContainer);
+    }
+
    @Test
    public void testPlaceActivityInTopContainer() {
        mSplitController.placeActivityInTopContainer(mActivity);
@@ -787,11 +833,7 @@ public class SplitControllerTest {
        final Activity activityBelow = createMockActivity();
        setupSplitRule(mActivity, activityBelow);

-        ActivityInfo aInfo = new ActivityInfo();
-        final Rect primaryBounds = getSplitBounds(true /* isPrimary */);
-        aInfo.windowLayout = new ActivityInfo.WindowLayout(0, 0, 0, 0, 0,
-                primaryBounds.width() + 1, primaryBounds.height() + 1);
-        doReturn(aInfo).when(mActivity).getActivityInfo();
+        doReturn(createActivityInfoWithMinDimensions()).when(mActivity).getActivityInfo();

        final TaskFragmentContainer container = mSplitController.newContainer(activityBelow,
                TASK_ID);
@@ -810,17 +852,12 @@ public class SplitControllerTest {
        final Activity activityBelow = createMockActivity();
        setupSplitRule(activityBelow, mActivity);

-        ActivityInfo aInfo = new ActivityInfo();
-        final Rect secondaryBounds = getSplitBounds(false /* isPrimary */);
-        aInfo.windowLayout = new ActivityInfo.WindowLayout(0, 0, 0, 0, 0,
-                secondaryBounds.width() + 1, secondaryBounds.height() + 1);
-        doReturn(aInfo).when(mActivity).getActivityInfo();
+        doReturn(createActivityInfoWithMinDimensions()).when(mActivity).getActivityInfo();

        final TaskFragmentContainer container = mSplitController.newContainer(activityBelow,
                TASK_ID);
        container.addPendingAppearedActivity(mActivity);

-        // Allow to split as primary.
        boolean result = mSplitController.resolveActivityToContainer(mActivity,
                false /* isOnReparent */);

@@ -828,6 +865,29 @@ public class SplitControllerTest {
        assertSplitPair(activityBelow, mActivity, true /* matchParentBounds */);
    }

+    // Suppress GuardedBy warning on unit tests
+    @SuppressWarnings("GuardedBy")
+    @Test
+    public void testResolveActivityToContainer_minDimensions_shouldExpandSplitContainer() {
+        final Activity primaryActivity = createMockActivity();
+        final Activity secondaryActivity = createMockActivity();
+        addSplitTaskFragments(primaryActivity, secondaryActivity, false /* clearTop */);
+
+        setupSplitRule(primaryActivity, mActivity, false /* clearTop */);
+        doReturn(createActivityInfoWithMinDimensions()).when(mActivity).getActivityInfo();
+        doReturn(secondaryActivity).when(mSplitController).findActivityBelow(eq(mActivity));
+
+        clearInvocations(mSplitPresenter);
+        boolean result = mSplitController.resolveActivityToContainer(mActivity,
+                false /* isOnReparent */);
+
+        assertTrue(result);
+        assertSplitPair(primaryActivity, mActivity, true /* matchParentBounds */);
+        assertEquals(mSplitController.getContainerWithActivity(secondaryActivity),
+                mSplitController.getContainerWithActivity(mActivity));
+        verify(mSplitPresenter, never()).createNewSplitContainer(any(), any(), any());
+    }
+
    @Test
    public void testResolveActivityToContainer_inUnknownTaskFragment() {
        doReturn(new Binder()).when(mSplitController).getInitialTaskFragmentToken(mActivity);
@@ -944,23 +1004,41 @@ public class SplitControllerTest {
    /** Setups a rule to always split the given activities. */
    private void setupSplitRule(@NonNull Activity primaryActivity,
            @NonNull Intent secondaryIntent) {
-        final SplitRule splitRule = createSplitRule(primaryActivity, secondaryIntent);
+        setupSplitRule(primaryActivity, secondaryIntent, true /* clearTop */);
+    }
+
+    /** Setups a rule to always split the given activities. */
+    private void setupSplitRule(@NonNull Activity primaryActivity,
+            @NonNull Intent secondaryIntent, boolean clearTop) {
+        final SplitRule splitRule = createSplitRule(primaryActivity, secondaryIntent, clearTop);
        mSplitController.setEmbeddingRules(Collections.singleton(splitRule));
    }

    /** Setups a rule to always split the given activities. */
    private void setupSplitRule(@NonNull Activity primaryActivity,
            @NonNull Activity secondaryActivity) {
-        final SplitRule splitRule = createSplitRule(primaryActivity, secondaryActivity);
+        setupSplitRule(primaryActivity, secondaryActivity, true /* clearTop */);
+    }
+
+    /** Setups a rule to always split the given activities. */
+    private void setupSplitRule(@NonNull Activity primaryActivity,
+            @NonNull Activity secondaryActivity, boolean clearTop) {
+        final SplitRule splitRule = createSplitRule(primaryActivity, secondaryActivity, clearTop);
        mSplitController.setEmbeddingRules(Collections.singleton(splitRule));
    }

    /** Adds a pair of TaskFragments as split for the given activities. */
    private void addSplitTaskFragments(@NonNull Activity primaryActivity,
            @NonNull Activity secondaryActivity) {
+        addSplitTaskFragments(primaryActivity, secondaryActivity, true /* clearTop */);
+    }
+
+    /** Adds a pair of TaskFragments as split for the given activities. */
+    private void addSplitTaskFragments(@NonNull Activity primaryActivity,
+            @NonNull Activity secondaryActivity, boolean clearTop) {
        registerSplitPair(createMockTaskFragmentContainer(primaryActivity),
                createMockTaskFragmentContainer(secondaryActivity),
-                createSplitRule(primaryActivity, secondaryActivity));
+                createSplitRule(primaryActivity, secondaryActivity, clearTop));
    }

    /** Registers the two given TaskFragments as split pair. */
@@ -1011,16 +1089,18 @@ public class SplitControllerTest {
        if (primaryContainer.mInfo != null) {
            final Rect primaryBounds = matchParentBounds ? new Rect()
                    : getSplitBounds(true /* isPrimary */);
+            final int windowingMode = matchParentBounds ? WINDOWING_MODE_UNDEFINED
+                    : WINDOWING_MODE_MULTI_WINDOW;
            assertTrue(primaryContainer.areLastRequestedBoundsEqual(primaryBounds));
-            assertTrue(primaryContainer.isLastRequestedWindowingModeEqual(
-                    WINDOWING_MODE_MULTI_WINDOW));
+            assertTrue(primaryContainer.isLastRequestedWindowingModeEqual(windowingMode));
        }
        if (secondaryContainer.mInfo != null) {
            final Rect secondaryBounds = matchParentBounds ? new Rect()
                    : getSplitBounds(false /* isPrimary */);
+            final int windowingMode = matchParentBounds ? WINDOWING_MODE_UNDEFINED
+                    : WINDOWING_MODE_MULTI_WINDOW;
            assertTrue(secondaryContainer.areLastRequestedBoundsEqual(secondaryBounds));
-            assertTrue(secondaryContainer.isLastRequestedWindowingModeEqual(
-                    WINDOWING_MODE_MULTI_WINDOW));
+            assertTrue(secondaryContainer.isLastRequestedWindowingModeEqual(windowingMode));
        }
    }
 }
--- a/libs/WindowManager/Jetpack/tests/unittest/src/androidx/window/extensions/embedding/SplitPresenterTest.java
+++ b/libs/WindowManager/Jetpack/tests/unittest/src/androidx/window/extensions/embedding/SplitPresenterTest.java
@@ -20,11 +20,16 @@ import static android.app.WindowConfiguration.WINDOWING_MODE_MULTI_WINDOW;

 import static androidx.window.extensions.embedding.EmbeddingTestUtils.TASK_BOUNDS;
 import static androidx.window.extensions.embedding.EmbeddingTestUtils.TASK_ID;
+import static androidx.window.extensions.embedding.EmbeddingTestUtils.createActivityInfoWithMinDimensions;
+import static androidx.window.extensions.embedding.EmbeddingTestUtils.createMockTaskFragmentInfo;
 import static androidx.window.extensions.embedding.EmbeddingTestUtils.createSplitRule;
 import static androidx.window.extensions.embedding.EmbeddingTestUtils.getSplitBounds;
 import static androidx.window.extensions.embedding.SplitPresenter.POSITION_END;
 import static androidx.window.extensions.embedding.SplitPresenter.POSITION_FILL;
 import static androidx.window.extensions.embedding.SplitPresenter.POSITION_START;
+import static androidx.window.extensions.embedding.SplitPresenter.RESULT_EXPANDED;
+import static androidx.window.extensions.embedding.SplitPresenter.RESULT_EXPAND_FAILED_NO_TF_INFO;
+import static androidx.window.extensions.embedding.SplitPresenter.RESULT_NOT_EXPANDED;
 import static androidx.window.extensions.embedding.SplitPresenter.getBoundsForPosition;
 import static androidx.window.extensions.embedding.SplitPresenter.getMinDimensions;
 import static androidx.window.extensions.embedding.SplitPresenter.shouldShowSideBySide;
@@ -34,6 +39,7 @@ import static com.android.dx.mockito.inline.extended.ExtendedMockito.verify;

 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyInt;
@@ -49,6 +55,7 @@ import android.content.pm.ActivityInfo;
 import android.content.res.Configuration;
 import android.content.res.Resources;
 import android.graphics.Rect;
+import android.os.IBinder;
 import android.platform.test.annotations.Presubmit;
 import android.util.Pair;
 import android.util.Size;
@@ -195,6 +202,52 @@ public class SplitPresenterTest {
                        splitRule, mActivity, minDimensionsPair));
    }

+    @Test
+    public void testExpandSplitContainerIfNeeded() {
+        SplitContainer splitContainer = mock(SplitContainer.class);
+        Activity secondaryActivity = createMockActivity();
+        SplitRule splitRule = createSplitRule(mActivity, secondaryActivity);
+        TaskFragmentContainer primaryTf = mController.newContainer(mActivity, TASK_ID);
+        TaskFragmentContainer secondaryTf = mController.newContainer(secondaryActivity, TASK_ID);
+        doReturn(splitRule).when(splitContainer).getSplitRule();
+        doReturn(primaryTf).when(splitContainer).getPrimaryContainer();
+        doReturn(secondaryTf).when(splitContainer).getSecondaryContainer();
+
+        assertThrows(IllegalArgumentException.class, () ->
+                mPresenter.expandSplitContainerIfNeeded(mTransaction, splitContainer, mActivity,
+                        null /* secondaryActivity */, null /* secondaryIntent */));
+
+        assertEquals(RESULT_NOT_EXPANDED, mPresenter.expandSplitContainerIfNeeded(mTransaction,
+                splitContainer, mActivity, secondaryActivity, null /* secondaryIntent */));
+        verify(mPresenter, never()).expandTaskFragment(any(), any());
+
+        doReturn(createActivityInfoWithMinDimensions()).when(secondaryActivity).getActivityInfo();
+        assertEquals(RESULT_EXPAND_FAILED_NO_TF_INFO, mPresenter.expandSplitContainerIfNeeded(
+                mTransaction, splitContainer, mActivity, secondaryActivity,
+                null /* secondaryIntent */));
+
+        primaryTf.setInfo(createMockTaskFragmentInfo(primaryTf, mActivity));
+        secondaryTf.setInfo(createMockTaskFragmentInfo(secondaryTf, secondaryActivity));
+
+        assertEquals(RESULT_EXPANDED, mPresenter.expandSplitContainerIfNeeded(mTransaction,
+                splitContainer, mActivity, secondaryActivity, null /* secondaryIntent */));
+        verify(mPresenter).expandTaskFragment(eq(mTransaction),
+                eq(primaryTf.getTaskFragmentToken()));
+        verify(mPresenter).expandTaskFragment(eq(mTransaction),
+                eq(secondaryTf.getTaskFragmentToken()));
+
+        clearInvocations(mPresenter);
+
+        assertEquals(RESULT_EXPANDED, mPresenter.expandSplitContainerIfNeeded(mTransaction,
+                splitContainer, mActivity, null /* secondaryActivity */,
+                new Intent(ApplicationProvider.getApplicationContext(),
+                        MinimumDimensionActivity.class)));
+        verify(mPresenter).expandTaskFragment(eq(mTransaction),
+                eq(primaryTf.getTaskFragmentToken()));
+        verify(mPresenter).expandTaskFragment(eq(mTransaction),
+                eq(secondaryTf.getTaskFragmentToken()));
+    }
+
    private Activity createMockActivity() {
        final Activity activity = mock(Activity.class);
        final Configuration activityConfig = new Configuration();
@@ -203,6 +256,7 @@ public class SplitPresenterTest {
        doReturn(mActivityResources).when(activity).getResources();
        doReturn(activityConfig).when(mActivityResources).getConfiguration();
        doReturn(new ActivityInfo()).when(activity).getActivityInfo();
+        doReturn(mock(IBinder.class)).when(activity).getActivityToken();
        return activity;
    }
 }