Disable recently used apps in battery saver mode.

UsageStats query is too slow.

Change-Id: I53fa13924514e71221d3a6407139ff00ae5eb378
Fixes: 114788699
Test: robotests

src/com/android/settings/applications/RecentAppsPreferenceController.java

@@ -25,6 +25,7 @@ import android.app.usage.UsageStatsManager;
 import android.content.Context;
 import android.content.Intent;
 import android.content.pm.PackageManager;
+import android.os.PowerManager;
 import android.os.UserHandle;
 import android.text.TextUtils;
 import android.util.ArrayMap;
@@ -78,6 +79,7 @@ public class RecentAppsPreferenceController extends AbstractPreferenceController
     private final ApplicationsState mApplicationsState;
     private final int mUserId;
     private final IconDrawableFactory mIconDrawableFactory;
+    private final PowerManager mPowerManager;
 
     private Calendar mCal;
     private List<UsageStats> mStats;
@@ -108,6 +110,8 @@ public class RecentAppsPreferenceController extends AbstractPreferenceController
         mIconDrawableFactory = IconDrawableFactory.newInstance(context);
         mUserId = UserHandle.myUserId();
         mPm = context.getPackageManager();
+        mPowerManager = context.getSystemService(PowerManager.class);
+
         mHost = host;
         mUsageStatsManager =
                 (UsageStatsManager) context.getSystemService(Context.USAGE_STATS_SERVICE);
@@ -183,7 +187,9 @@ public class RecentAppsPreferenceController extends AbstractPreferenceController
     void reloadData() {
         mCal = Calendar.getInstance();
         mCal.add(Calendar.DAY_OF_YEAR, -1);
-        mStats = mUsageStatsManager.queryUsageStats(
+        mStats = mPowerManager.isPowerSaveMode()
+                ? new ArrayList<>()
+                : mUsageStatsManager.queryUsageStats(
                         UsageStatsManager.INTERVAL_BEST, mCal.getTimeInMillis(),
                         System.currentTimeMillis());
     }
@@ -301,7 +307,8 @@ public class RecentAppsPreferenceController extends AbstractPreferenceController
     private boolean shouldIncludePkgInRecents(UsageStats stat) {
         final String pkgName = stat.getPackageName();
         if (stat.getLastTimeUsed() < mCal.getTimeInMillis()) {
-            Log.d(TAG, "Invalid timestamp, skipping " + pkgName);
+            Log.d(TAG, "Invalid timestamp (usage time is more than 24 hours ago), skipping "
+                    + pkgName);
             return false;
         }
 

tests/robotests/src/com/android/settings/applications/RecentAppsPreferenceControllerTest.java

@@ -40,6 +40,7 @@ import android.content.Intent;
 import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageManager;
 import android.content.pm.ResolveInfo;
+import android.os.PowerManager;
 import android.os.UserHandle;
 import android.os.UserManager;
 import android.text.TextUtils;
@@ -50,6 +51,7 @@ import androidx.preference.PreferenceScreen;
 
 import com.android.settings.R;
 import com.android.settings.testutils.SettingsRobolectricTestRunner;
+import com.android.settings.testutils.shadow.ShadowPowerManager;
 import com.android.settingslib.applications.AppUtils;
 import com.android.settingslib.applications.ApplicationsState;
 import com.android.settingslib.applications.instantapps.InstantAppDataProvider;
@@ -195,6 +197,35 @@ public class RecentAppsPreferenceControllerTest {
         verify(mDivider).setVisible(true);
     }
 
+    @Test
+    public void display_powerSaverMode_showNoRecents() {
+        mContext.getSystemService(PowerManager.class).setPowerSaveMode(true);
+
+        final List<UsageStats> stats = new ArrayList<>();
+        final UsageStats stat1 = new UsageStats();
+
+        stat1.mLastTimeUsed = System.currentTimeMillis();
+        stat1.mPackageName = "pkg.class";
+        stats.add(stat1);
+
+        // stat1, stat2 are valid apps. stat3 is invalid.
+        when(mAppState.getEntry(stat1.mPackageName, UserHandle.myUserId()))
+                .thenReturn(mAppEntry);
+        when(mPackageManager.resolveActivity(any(Intent.class), anyInt()))
+                .thenReturn(new ResolveInfo());
+        when(mUsageStatsManager.queryUsageStats(anyInt(), anyLong(), anyLong()))
+                .thenReturn(stats);
+        mAppEntry.info = mApplicationInfo;
+
+        mController.displayPreference(mScreen);
+
+        verify(mCategory, never()).addPreference(any(Preference.class));
+        verify(mCategory).setTitle(null);
+        verify(mSeeAllPref).setTitle(R.string.applications_settings);
+        verify(mSeeAllPref).setIcon(null);
+        verify(mDivider).setVisible(false);
+    }
+
     @Test
     public void display_showRecentsWithInstantApp() {
         // Regular app.