Merge "Fix flicker for AppDataUsage when zero usage" into tm-dev am: 98429fbe65

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Settings/+/18617746

Change-Id: I47ff02a503fd52cd79be438647d0f45c74c22a11
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

src/com/android/settings/datausage/AppDataUsage.java

@@ -40,6 +40,8 @@ import androidx.loader.content.Loader;
 import androidx.preference.Preference;
 import androidx.preference.Preference.OnPreferenceChangeListener;
 import androidx.preference.PreferenceCategory;
+import androidx.recyclerview.widget.DefaultItemAnimator;
+import androidx.recyclerview.widget.RecyclerView;
 
 import com.android.settings.R;
 import com.android.settings.applications.AppInfoBase;
@@ -105,6 +107,7 @@ public class AppDataUsage extends DataUsageBaseFragment implements OnPreferenceC
     private Context mContext;
     private ArrayList<Long> mCycles;
     private long mSelectedCycle;
+    private boolean mIsLoading;
 
     @Override
     public void onCreate(Bundle icicle) {
@@ -226,6 +229,16 @@ public class AppDataUsage extends DataUsageBaseFragment implements OnPreferenceC
     @Override
     public void onResume() {
         super.onResume();
+        // No animations will occur before:
+        //  - LOADER_APP_USAGE_DATA initially updates the cycle
+        //  - updatePrefs() initially updates the preference visibility
+        // This is mainly for the cycle spinner, because when the page is entered from the
+        // AppInfoDashboardFragment, there is no way to know whether the cycle data is available
+        // before finished the async loading.
+        // The animator will be set back if any page updates happens after loading, in
+        // setBackPreferenceListAnimatorIfLoaded().
+        mIsLoading = true;
+        getListView().setItemAnimator(null);
         if (mDataSaverBackend != null) {
             mDataSaverBackend.addListener(this);
         }
@@ -297,7 +310,25 @@ public class AppDataUsage extends DataUsageBaseFragment implements OnPreferenceC
         }
     }
 
+    /**
+     * Sets back the preference list's animator if the loading is finished.
+     *
+     * The preference list's animator was temporarily removed before loading in onResume().
+     * When need to update the preference visibility in this page after the loading, adding the
+     * animator back to keeping the usual animations.
+     */
+    private void setBackPreferenceListAnimatorIfLoaded() {
+        if (mIsLoading) {
+            return;
+        }
+        RecyclerView recyclerView = getListView();
+        if (recyclerView.getItemAnimator() == null) {
+            recyclerView.setItemAnimator(new DefaultItemAnimator());
+        }
+    }
+
     private void updatePrefs(boolean restrictBackground, boolean unrestrictData) {
+        setBackPreferenceListAnimatorIfLoaded();
         final EnforcedAdmin admin = RestrictedLockUtilsInternal.checkIfMeteredDataRestricted(
                 mContext, mPackageName, UserHandle.getUserId(mAppItem.key));
         if (mRestrictBackground != null) {
@@ -448,6 +479,7 @@ public class AppDataUsage extends DataUsageBaseFragment implements OnPreferenceC
                 } else {
                     bindData(0 /* position */);
                 }
+                mIsLoading = false;
             }
 
             @Override

tests/robotests/src/com/android/settings/datausage/AppDataUsageTest.java

@@ -48,6 +48,7 @@ import androidx.fragment.app.FragmentActivity;
 import androidx.preference.Preference;
 import androidx.preference.PreferenceManager;
 import androidx.preference.PreferenceScreen;
+import androidx.recyclerview.widget.RecyclerView;
 
 import com.android.settings.applications.AppInfoBase;
 import com.android.settings.testutils.FakeFeatureFactory;
@@ -240,6 +241,7 @@ public class AppDataUsageTest {
         ReflectionHelpers.setField(mFragment, "mUnrestrictedData", unrestrictedDataPref);
         ReflectionHelpers.setField(mFragment, "mDataSaverBackend", dataSaverBackend);
         ReflectionHelpers.setField(mFragment.services, "mPolicyManager", networkPolicyManager);
+        when(mFragment.getListView()).thenReturn(mock(RecyclerView.class));
 
         ShadowRestrictedLockUtilsInternal.setRestricted(true);
         doReturn(NetworkPolicyManager.POLICY_NONE).when(networkPolicyManager)