Clear static icon and label cache if ui mode is changed

we should clear icon cache if theme is changed between light and dark
theme, otherwise we may show incorrect styled icon for applications

Bug: 185187729
Test: make SettingsRoboTests
Change-Id: Ib06abe5a5345b2ea363a04ecaec886a4765fd8ab

src/com/android/settings/fuelgauge/BatteryChartPreferenceController.java

@@ -17,6 +17,7 @@
 package com.android.settings.fuelgauge;
 
 import android.content.Context;
+import android.content.res.Configuration;
 import android.graphics.drawable.Drawable;
 import android.os.Bundle;
 import android.os.Handler;
@@ -39,6 +40,7 @@ import com.android.settingslib.core.lifecycle.Lifecycle;
 import com.android.settingslib.core.lifecycle.LifecycleObserver;
 import com.android.settingslib.core.lifecycle.events.OnCreate;
 import com.android.settingslib.core.lifecycle.events.OnDestroy;
+import com.android.settingslib.core.lifecycle.events.OnResume;
 import com.android.settingslib.core.lifecycle.events.OnSaveInstanceState;
 import com.android.settingslib.utils.StringUtil;
 
@@ -53,7 +55,7 @@ import java.util.Map;
 /** Controls the update for chart graph and the list items. */
 public class BatteryChartPreferenceController extends AbstractPreferenceController
         implements PreferenceControllerMixin, LifecycleObserver, OnCreate, OnDestroy,
-                OnSaveInstanceState, BatteryChartView.OnSelectListener,
+                OnSaveInstanceState, BatteryChartView.OnSelectListener, OnResume,
                 ExpandDividerPreference.OnExpandListener {
     private static final String TAG = "BatteryChartPreferenceController";
     /** Desired battery history size for timestamp slots. */
@@ -67,6 +69,8 @@ public class BatteryChartPreferenceController extends AbstractPreferenceControll
     private static final String KEY_EXPAND_SYSTEM_INFO = "expand_system_info";
     private static final String KEY_CURRENT_TIME_SLOT = "current_time_slot";
 
+    private static int sUiMode = Configuration.UI_MODE_NIGHT_UNDEFINED;
+
     @VisibleForTesting
     Map<Integer, List<BatteryDiffEntry>> mBatteryIndexedMap;
 
@@ -124,6 +128,18 @@ public class BatteryChartPreferenceController extends AbstractPreferenceControll
             mTrapezoidIndex, mIsExpanded));
     }
 
+    @Override
+    public void onResume() {
+        final int currentUiMode =
+            mContext.getResources().getConfiguration().uiMode
+                & Configuration.UI_MODE_NIGHT_MASK;
+        if (sUiMode != currentUiMode) {
+            sUiMode = currentUiMode;
+            BatteryDiffEntry.clearCache();
+            Log.d(TAG, "clear icon and label cache since uiMode is changed");
+        }
+    }
+
     @Override
     public void onSaveInstanceState(Bundle savedInstance) {
         if (savedInstance == null) {

tests/robotests/src/com/android/settings/fuelgauge/BatteryChartPreferenceControllerTest.java

@@ -29,6 +29,8 @@ import static org.mockito.Mockito.when;
 import android.content.Context;
 import android.content.ContentValues;
 import android.content.pm.PackageManager;
+import android.content.res.Configuration;
+import android.content.res.Resources;
 import android.graphics.drawable.Drawable;
 import android.os.Bundle;
 import android.text.format.DateUtils;
@@ -76,6 +78,8 @@ public final class BatteryChartPreferenceControllerTest {
     @Mock private PowerGaugePreference mPowerGaugePreference;
     @Mock private ExpandDividerPreference mExpandDividerPreference;
     @Mock private BatteryUtils mBatteryUtils;
+    @Mock private Configuration mConfiguration;
+    @Mock private Resources mResources;
 
     private Context mContext;
     private BatteryDiffEntry mBatteryDiffEntry;
@@ -104,6 +108,33 @@ public final class BatteryChartPreferenceControllerTest {
             createBatteryHistoryMap());
     }
 
+    @Test
+    public void testOnResume_uiModeIsChanged_clearBatteryDiffEntryCache() {
+        doReturn(mResources).when(mContext).getResources();
+        doReturn(mConfiguration).when(mResources).getConfiguration();
+        mConfiguration.uiMode = Configuration.UI_MODE_NIGHT_UNDEFINED;
+        // Ensures the testing environment is correct.
+        assertThat(BatteryDiffEntry.sResourceCache).hasSize(1);
+        mBatteryChartPreferenceController.onResume();
+        // Changes the uiMode in the configuration.
+        mConfiguration.uiMode = Configuration.UI_MODE_NIGHT_YES;
+
+        mBatteryChartPreferenceController.onResume();
+        assertThat(BatteryDiffEntry.sResourceCache).isEmpty();
+    }
+
+    @Test
+    public void testOnResume_uiModeIsNotChanged_notClearBatteryDiffEntryCache() {
+        doReturn(mResources).when(mContext).getResources();
+        doReturn(mConfiguration).when(mResources).getConfiguration();
+        mConfiguration.uiMode = Configuration.UI_MODE_NIGHT_UNDEFINED;
+        // Ensures the testing environment is correct.
+        assertThat(BatteryDiffEntry.sResourceCache).hasSize(1);
+
+        mBatteryChartPreferenceController.onResume();
+        assertThat(BatteryDiffEntry.sResourceCache).isNotEmpty();
+    }
+
     @Test
     public void testOnDestroy_activityIsChanging_clearBatteryEntryCache() {
         doReturn(true).when(mSettingsActivity).isChangingConfigurations();