Grey out and disable tabs when selecting files.

Bug: 149614174
Test: manual
Test: atest DocumentsUIGoogleTests:com.android.documentsui.ProfileTabsControllerTest
Change-Id: I205c13b314a5ea196b00e5fd32525237653af09b

11 files changed, 239 insertions, 2 deletions

diff --git a/src/com/android/documentsui/BaseActivity.java b/src/com/android/documentsui/BaseActivity.java
index c5726d9eb..079f33244 100644
--- a/src/com/android/documentsui/BaseActivity.java
+++ b/src/com/android/documentsui/BaseActivity.java
@@ -434,6 +434,10 @@ public abstract class BaseActivity
         updateHeaderTitle();
     }
 
+    protected ProfileTabsAddons getProfileTabsAddon() {
+        return mNavigator.getProfileTabsAddons();
+    }
+
     @Override
     public boolean onOptionsItemSelected(MenuItem item) {
 
diff --git a/src/com/android/documentsui/DummyProfileTabsAddons.java b/src/com/android/documentsui/DummyProfileTabsAddons.java
new file mode 100644
index 000000000..697025e23
--- /dev/null
+++ b/src/com/android/documentsui/DummyProfileTabsAddons.java
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.documentsui;
+
+/**
+ * A dummy {@ProfileTabsAddons} implementation.
+ */
+public class DummyProfileTabsAddons implements ProfileTabsAddons {
+
+    @Override
+    public void setEnabled(boolean enabled) {
+        // Do nothing.
+    }
+}
diff --git a/src/com/android/documentsui/Injector.java b/src/com/android/documentsui/Injector.java
index d6c631247..5761566c1 100644
--- a/src/com/android/documentsui/Injector.java
+++ b/src/com/android/documentsui/Injector.java
@@ -21,6 +21,7 @@ import static java.lang.annotation.RetentionPolicy.SOURCE;
 import android.view.MenuItem;
 
 import androidx.annotation.Nullable;
+import androidx.annotation.VisibleForTesting;
 import androidx.recyclerview.selection.SelectionTracker;
 import androidx.recyclerview.widget.RecyclerView;
 
@@ -36,7 +37,6 @@ import com.android.documentsui.prefs.ScopedPreferences;
 import com.android.documentsui.queries.SearchViewManager;
 import com.android.documentsui.ui.DialogController;
 import com.android.documentsui.ui.MessageBuilder;
-import androidx.annotation.VisibleForTesting;
 
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
@@ -68,6 +68,9 @@ public class Injector<T extends ActionHandler> {
     public ActionModeController actionModeController;
 
     @ContentScoped
+    public ProfileTabsController profileTabsController;
+
+    @ContentScoped
     public T actions;
 
     @ContentScoped
diff --git a/src/com/android/documentsui/NavigationViewManager.java b/src/com/android/documentsui/NavigationViewManager.java
index aca8c31b5..ed4acf6aa 100644
--- a/src/com/android/documentsui/NavigationViewManager.java
+++ b/src/com/android/documentsui/NavigationViewManager.java
@@ -106,6 +106,10 @@ public class NavigationViewManager {
         mSearchBarView.setOnClickListener(listener);
     }
 
+    public ProfileTabsAddons getProfileTabsAddons() {
+        return mProfileTabs;
+    }
+
     private void onNavigationIconClicked() {
         if (mDrawer.isPresent()) {
             mDrawer.setOpen(true);
diff --git a/src/com/android/documentsui/ProfileTabs.java b/src/com/android/documentsui/ProfileTabs.java
index 24a36b2b7..f9e195ba5 100644
--- a/src/com/android/documentsui/ProfileTabs.java
+++ b/src/com/android/documentsui/ProfileTabs.java
@@ -19,6 +19,7 @@ package com.android.documentsui;
 import static androidx.core.util.Preconditions.checkNotNull;
 
 import android.view.View;
+import android.view.ViewGroup;
 
 import androidx.annotation.VisibleForTesting;
 
@@ -33,7 +34,8 @@ import java.util.List;
 /**
  * A manager class to control UI on a {@link TabLayout} for cross-profile purpose.
  */
-public class ProfileTabs {
+public class ProfileTabs implements ProfileTabsAddons {
+    private static final float DISABLED_TAB_OPACITY = 0.38f;
 
     private final TabLayout mTabs;
     private final State mState;
@@ -103,4 +105,20 @@ public class ProfileTabs {
     private TabLayout.Tab createTab(int resId, UserId userId) {
         return mTabs.newTab().setText(resId).setTag(userId);
     }
+
+    @Override
+    public void setEnabled(boolean enabled) {
+        if (mTabs.getChildCount() > 0) {
+            View view = mTabs.getChildAt(0);
+            if (view instanceof ViewGroup) {
+                ViewGroup tabs = (ViewGroup) view;
+                for (int i = 0; i < tabs.getChildCount(); i++) {
+                    View tabView = tabs.getChildAt(i);
+                    tabView.setEnabled(enabled);
+                    tabView.setAlpha((enabled || mTabs.getSelectedTabPosition() == i) ? 1f
+                            : DISABLED_TAB_OPACITY);
+                }
+            }
+        }
+    }
 }
diff --git a/src/com/android/documentsui/ProfileTabsAddons.java b/src/com/android/documentsui/ProfileTabsAddons.java
new file mode 100644
index 000000000..885d29828
--- /dev/null
+++ b/src/com/android/documentsui/ProfileTabsAddons.java
@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.documentsui;
+
+/**
+ * Provides methods to control a {@link ProfileTabs}.
+ */
+public interface ProfileTabsAddons {
+    /**
+     * Enables/Disables the profile tabs.
+     */
+    void setEnabled(boolean enabled);
+}
diff --git a/src/com/android/documentsui/ProfileTabsController.java b/src/com/android/documentsui/ProfileTabsController.java
new file mode 100644
index 000000000..d10806b4f
--- /dev/null
+++ b/src/com/android/documentsui/ProfileTabsController.java
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.documentsui;
+
+import androidx.recyclerview.selection.SelectionTracker;
+import androidx.recyclerview.selection.SelectionTracker.SelectionObserver;
+
+/**
+ * A controller that listens to selection changes and control profile tabs behavior.
+ */
+public class ProfileTabsController extends SelectionObserver<String> {
+
+    private static final String TAG = "ProfileTabsController";
+
+    private final SelectionTracker<String> mSelectionMgr;
+    private final ProfileTabsAddons mProfileTabsAddons;
+
+    public ProfileTabsController(
+            SelectionTracker<String> selectionMgr,
+            ProfileTabsAddons profileTabsAddons) {
+        mSelectionMgr = selectionMgr;
+        mProfileTabsAddons = profileTabsAddons;
+    }
+
+    @Override
+    public void onSelectionChanged() {
+        mProfileTabsAddons.setEnabled(mSelectionMgr.getSelection().isEmpty());
+    }
+
+    @Override
+    public void onSelectionRestored() {
+        onSelectionChanged();
+    }
+}
diff --git a/src/com/android/documentsui/dirlist/DirectoryFragment.java b/src/com/android/documentsui/dirlist/DirectoryFragment.java
index d82fdeb52..dcd2edd19 100644
--- a/src/com/android/documentsui/dirlist/DirectoryFragment.java
+++ b/src/com/android/documentsui/dirlist/DirectoryFragment.java
@@ -79,6 +79,7 @@ import com.android.documentsui.Injector.Injected;
 import com.android.documentsui.MetricConsts;
 import com.android.documentsui.Metrics;
 import com.android.documentsui.Model;
+import com.android.documentsui.ProfileTabsController;
 import com.android.documentsui.R;
 import com.android.documentsui.ThumbnailCache;
 import com.android.documentsui.base.DocumentFilters;
@@ -155,6 +156,10 @@ public class DirectoryFragment extends Fragment implements SwipeRefreshLayout.On
     @ContentScoped
     private ActionModeController mActionModeController;
 
+    @Injected
+    @ContentScoped
+    private ProfileTabsController mProfileTabsController;
+
     private DocDetailsLookup mDetailsLookup;
     private SelectionMetadata mSelectionMetadata;
     private KeyInputHandler mKeyListener;
@@ -402,6 +407,9 @@ public class DirectoryFragment extends Fragment implements SwipeRefreshLayout.On
 
         mSelectionMgr.addObserver(mActionModeController);
 
+        mProfileTabsController = mInjector.profileTabsController;
+        mSelectionMgr.addObserver(mProfileTabsController);
+
         final ActivityManager am = (ActivityManager) mActivity.getSystemService(
                 Context.ACTIVITY_SERVICE);
         boolean svelte = am.isLowRamDevice() && (mState.stack.isRecents());
diff --git a/src/com/android/documentsui/files/FilesActivity.java b/src/com/android/documentsui/files/FilesActivity.java
index 81ff61ff7..1d8909fbd 100644
--- a/src/com/android/documentsui/files/FilesActivity.java
+++ b/src/com/android/documentsui/files/FilesActivity.java
@@ -37,11 +37,14 @@ import com.android.documentsui.ActionModeController;
 import com.android.documentsui.BaseActivity;
 import com.android.documentsui.DocsSelectionHelper;
 import com.android.documentsui.DocumentsApplication;
+import com.android.documentsui.DummyProfileTabsAddons;
 import com.android.documentsui.FocusManager;
 import com.android.documentsui.Injector;
 import com.android.documentsui.MenuManager.DirectoryDetails;
 import com.android.documentsui.OperationDialogFragment;
 import com.android.documentsui.OperationDialogFragment.DialogType;
+import com.android.documentsui.ProfileTabsAddons;
+import com.android.documentsui.ProfileTabsController;
 import com.android.documentsui.ProviderExecutor;
 import com.android.documentsui.R;
 import com.android.documentsui.SharedInputHandler;
@@ -74,6 +77,7 @@ public class FilesActivity extends BaseActivity implements AbstractActionHandler
     private Injector<ActionHandler<FilesActivity>> mInjector;
     private ActivityInputHandler mActivityInputHandler;
     private SharedInputHandler mSharedInputHandler;
+    private final ProfileTabsAddons mProfileTabsAddonsStub = new DummyProfileTabsAddons();
 
     public FilesActivity() {
         super(R.layout.files_activity, TAG);
@@ -148,6 +152,12 @@ public class FilesActivity extends BaseActivity implements AbstractActionHandler
 
         mInjector.searchManager = mSearchManager;
 
+        // No profile tabs will be shown on FilesActivity. Use a dummy to avoid unnecessary
+        // operations.
+        mInjector.profileTabsController = new ProfileTabsController(
+                mInjector.selectionMgr,
+                mProfileTabsAddonsStub);
+
         mAppsRowManager = new AppsRowManager(mInjector.actions);
         mInjector.appsRowManager = mAppsRowManager;
 
diff --git a/src/com/android/documentsui/picker/PickActivity.java b/src/com/android/documentsui/picker/PickActivity.java
index f7f2ebe80..f1a33098f 100644
--- a/src/com/android/documentsui/picker/PickActivity.java
+++ b/src/com/android/documentsui/picker/PickActivity.java
@@ -46,6 +46,7 @@ import com.android.documentsui.FocusManager;
 import com.android.documentsui.Injector;
 import com.android.documentsui.MenuManager.DirectoryDetails;
 import com.android.documentsui.Metrics;
+import com.android.documentsui.ProfileTabsController;
 import com.android.documentsui.ProviderExecutor;
 import com.android.documentsui.R;
 import com.android.documentsui.SharedInputHandler;
@@ -121,6 +122,10 @@ public class PickActivity extends BaseActivity implements ActionHandler.Addons {
                 mInjector.menuManager,
                 mInjector.messages);
 
+        mInjector.profileTabsController = new ProfileTabsController(
+                mInjector.selectionMgr,
+                getProfileTabsAddon());
+
         mInjector.pickResult = getPickResult(icicle);
         mInjector.actions = new ActionHandler<>(
                 this,
diff --git a/tests/unit/com/android/documentsui/ProfileTabsControllerTest.java b/tests/unit/com/android/documentsui/ProfileTabsControllerTest.java
new file mode 100644
index 000000000..2c6b2f90e
--- /dev/null
+++ b/tests/unit/com/android/documentsui/ProfileTabsControllerTest.java
@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.documentsui;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import androidx.recyclerview.selection.SelectionTracker;
+import androidx.test.filters.SmallTest;
+
+import org.junit.Before;
+import org.junit.Test;
+
+@SmallTest
+public class ProfileTabsControllerTest {
+
+    private SelectionTracker<String> mSelectionMgr = SelectionHelpers.createTestInstance();
+    private Boolean testEnabledValue = null;
+    private ProfileTabsController mController = new ProfileTabsController(mSelectionMgr,
+            enabled -> testEnabledValue = enabled);
+
+    @Before
+    public void setUp() throws Exception {
+        mSelectionMgr.addObserver(mController);
+    }
+
+    @Test
+    public void testNoSelection_enable() {
+        mController.onSelectionRestored();
+        assertThat(testEnabledValue).isTrue();
+    }
+
+    @Test
+    public void testClearSelection_enable() {
+        mSelectionMgr.select("foo");
+        mSelectionMgr.clearSelection();
+        assertThat(testEnabledValue).isTrue();
+    }
+
+    @Test
+    public void testDeselectAll_enable() {
+        mSelectionMgr.select("foo");
+        mSelectionMgr.select("bar");
+        mSelectionMgr.deselect("foo");
+        mSelectionMgr.deselect("bar");
+        assertThat(testEnabledValue).isTrue();
+    }
+
+    @Test
+    public void testSelection_disable() {
+        mSelectionMgr.select("foo");
+        assertThat(testEnabledValue).isFalse();
+    }
+
+    @Test
+    public void testMultipleSelection_disable() {
+        mSelectionMgr.select("foo");
+        mSelectionMgr.select("bar");
+        mSelectionMgr.select("apple");
+        assertThat(testEnabledValue).isFalse();
+    }
+
+    @Test
+    public void testDeselectSome_Disable() {
+        mSelectionMgr.select("foo");
+        mSelectionMgr.select("bar");
+        mSelectionMgr.deselect("bar");
+        assertThat(testEnabledValue).isFalse();
+    }
+}