commit 9cd63c97cecba6e135d69c3034e43afef466ed0c
author Pinyao Ting <pinyaoting@google.com> Wed Jun 16 17:51:39 2021 +0000
committer Pinyao Ting <pinyaoting@google.com> Wed Jun 16 21:02:48 2021 +0000
tree 34afd2a1ecb14aa28b0c0766f178fb0c822ce545
parent f89c4280b31457faf2b272cbcc4d77be7868e866

Prevents a ConcurrentModificationException in Widget

InvariantDeviceProfile.supportedProfiles can be modified in respect to
configuration changes. This CL ensures the list was cloned before access
to prevent ConcurrentModificationException

Bug: 191231591
Test: manual
Change-Id: I123458dcfe99af4babca2cf73733e3d2af0fad3c

robolectric_tests/src/com/android/launcher3/widget/LauncherAppWidgetProviderInfoTest.java

diff --git a/robolectric_tests/src/com/android/launcher3/widget/LauncherAppWidgetProviderInfoTest.java b/robolectric_tests/src/com/android/launcher3/widget/LauncherAppWidgetProviderInfoTest.java
index c7286e5..2d87957 100644
--- a/robolectric_tests/src/com/android/launcher3/widget/LauncherAppWidgetProviderInfoTest.java
+++ b/robolectric_tests/src/com/android/launcher3/widget/LauncherAppWidgetProviderInfoTest.java
@@ -36,6 +36,10 @@
 import org.robolectric.RobolectricTestRunner;
 import org.robolectric.RuntimeEnvironment;
 
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
 @RunWith(RobolectricTestRunner.class)
 public final class LauncherAppWidgetProviderInfoTest {
 
@@ -234,10 +238,11 @@
         Mockito.when(profile.getCellSize()).thenReturn(new Point(CELL_SIZE, CELL_SIZE));
 
         InvariantDeviceProfile idp = new InvariantDeviceProfile();
-        idp.supportedProfiles.add(profile);
+        List<DeviceProfile> supportedProfiles = new ArrayList<>(idp.supportedProfiles);
+        supportedProfiles.add(profile);
+        idp.supportedProfiles = Collections.unmodifiableList(supportedProfiles);
         idp.numColumns = NUM_OF_COLS;
         idp.numRows = NUM_OF_ROWS;
         return idp;
     }
-
 }

src/com/android/launcher3/InvariantDeviceProfile.java

diff --git a/src/com/android/launcher3/InvariantDeviceProfile.java b/src/com/android/launcher3/InvariantDeviceProfile.java
index 318dde1..29a0223 100644
--- a/src/com/android/launcher3/InvariantDeviceProfile.java
+++ b/src/com/android/launcher3/InvariantDeviceProfile.java
@@ -140,7 +140,10 @@
     public int defaultLayoutId;
     int demoModeLayoutId;
 
-    public final List<DeviceProfile> supportedProfiles = new ArrayList<>();
+    /**
+     * An immutable list of supported profiles.
+     */
+    public List<DeviceProfile> supportedProfiles = Collections.EMPTY_LIST;
 
     @Nullable public DevicePaddings devicePaddings;
 
@@ -322,10 +325,10 @@
         // Supported overrides: numRows, numColumns, iconSize
         applyPartnerDeviceProfileOverrides(context, metrics);
 
-        supportedProfiles.clear();
+        final List<DeviceProfile> localSupportedProfiles = new ArrayList<>();
         defaultWallpaperSize = new Point(displayInfo.currentSize);
         for (WindowBounds bounds : displayInfo.supportedBounds) {
-            supportedProfiles.add(new DeviceProfile.Builder(context, this, displayInfo)
+            localSupportedProfiles.add(new DeviceProfile.Builder(context, this, displayInfo)
                     .setUseTwoPanels(isSplitDisplay)
                     .setWindowBounds(bounds).build());
 
@@ -343,6 +346,7 @@
             defaultWallpaperSize.x =
                     Math.max(defaultWallpaperSize.x, Math.round(parallaxFactor * displayWidth));
         }
+        supportedProfiles = Collections.unmodifiableList(localSupportedProfiles);
 
         ComponentName cn = new ComponentName(context.getPackageName(), getClass().getName());
         defaultWidgetPadding = AppWidgetHostView.getDefaultPaddingForWidget(context, cn, null);