diff --git a/libs/androidfw/ApkAssets.cpp b/libs/androidfw/ApkAssets.cpp
index a5b1d29..0e577d1 100644
--- a/libs/androidfw/ApkAssets.cpp
+++ b/libs/androidfw/ApkAssets.cpp
@@ -30,6 +30,8 @@
 
 namespace android {
 
+ApkAssets::ApkAssets() : zip_handle_(nullptr, ::CloseArchive) {}
+
 std::unique_ptr<const ApkAssets> ApkAssets::Load(const std::string& path, bool system) {
   return ApkAssets::LoadImpl(path, system, false /*load_as_shared_library*/);
 }
diff --git a/libs/androidfw/AssetManager2.cpp b/libs/androidfw/AssetManager2.cpp
index ab7e14d..f1f2e2d 100644
--- a/libs/androidfw/AssetManager2.cpp
+++ b/libs/androidfw/AssetManager2.cpp
@@ -902,26 +902,32 @@
     return true;
   }
 
-  if (asset_manager_ != o.asset_manager_) {
-    return false;
-  }
-
   type_spec_flags_ = o.type_spec_flags_;
 
+  const bool copy_only_system = asset_manager_ != o.asset_manager_;
+
   for (size_t p = 0; p < packages_.size(); p++) {
     const Package* package = o.packages_[p].get();
-    if (package == nullptr) {
+    if (package == nullptr || (copy_only_system && p != 0x01)) {
+      // The other theme doesn't have this package, clear ours.
       packages_[p].reset();
       continue;
     }
 
+    if (packages_[p] == nullptr) {
+      // The other theme has this package, but we don't. Make one.
+      packages_[p].reset(new Package());
+    }
+
     for (size_t t = 0; t < package->types.size(); t++) {
       const Type* type = package->types[t].get();
       if (type == nullptr) {
+        // The other theme doesn't have this type, clear ours.
         packages_[p]->types[t].reset();
         continue;
       }
 
+      // Create a new type and update it to theirs.
       const size_t type_alloc_size = sizeof(Type) + (type->entry_capacity * sizeof(Entry));
       void* copied_data = malloc(type_alloc_size);
       memcpy(copied_data, type, type_alloc_size);
diff --git a/libs/androidfw/include/androidfw/ApkAssets.h b/libs/androidfw/include/androidfw/ApkAssets.h
index b7e66fb..2e392d5 100644
--- a/libs/androidfw/include/androidfw/ApkAssets.h
+++ b/libs/androidfw/include/androidfw/ApkAssets.h
@@ -21,7 +21,6 @@
 #include <string>
 
 #include "android-base/macros.h"
-#include "ziparchive/zip_archive.h"
 
 #include "androidfw/Asset.h"
 #include "androidfw/LoadedArsc.h"
@@ -52,14 +51,9 @@
   static std::unique_ptr<const ApkAssets> LoadImpl(const std::string& path, bool system,
                                                    bool load_as_shared_library);
 
-  ApkAssets() = default;
+  ApkAssets();
 
-  struct ZipArchivePtrCloser {
-    void operator()(::ZipArchiveHandle handle) { ::CloseArchive(handle); }
-  };
-
-  using ZipArchivePtr =
-      std::unique_ptr<typename std::remove_pointer<::ZipArchiveHandle>::type, ZipArchivePtrCloser>;
+  using ZipArchivePtr = std::unique_ptr<void, void(*)(void*)>;
 
   ZipArchivePtr zip_handle_;
   std::string path_;
diff --git a/libs/androidfw/include/androidfw/AssetManager2.h b/libs/androidfw/include/androidfw/AssetManager2.h
index d2bc6ee..fd94144 100644
--- a/libs/androidfw/include/androidfw/AssetManager2.h
+++ b/libs/androidfw/include/androidfw/AssetManager2.h
@@ -70,9 +70,8 @@
 };
 
 // AssetManager2 is the main entry point for accessing assets and resources.
-// AssetManager2 provides caching of resources retrieved via the underlying
-// ApkAssets.
-class AssetManager2 : public ::AAssetManager {
+// AssetManager2 provides caching of resources retrieved via the underlying ApkAssets.
+class AssetManager2 {
  public:
   struct ResourceName {
     const char* package = nullptr;
diff --git a/libs/androidfw/tests/Theme_test.cpp b/libs/androidfw/tests/Theme_test.cpp
index dfff9c0..feb454e 100644
--- a/libs/androidfw/tests/Theme_test.cpp
+++ b/libs/androidfw/tests/Theme_test.cpp
@@ -23,6 +23,7 @@
 #include "data/lib_one/R.h"
 #include "data/libclient/R.h"
 #include "data/styles/R.h"
+#include "data/system/R.h"
 
 namespace app = com::android::app;
 namespace lib_one = com::android::lib_one;
@@ -33,6 +34,9 @@
 class ThemeTest : public ::testing::Test {
  public:
   void SetUp() override {
+    system_assets_ = ApkAssets::Load(GetTestDataPath() + "/system/system.apk", true /*system*/);
+    ASSERT_NE(nullptr, system_assets_);
+
     style_assets_ = ApkAssets::Load(GetTestDataPath() + "/styles/styles.apk");
     ASSERT_NE(nullptr, style_assets_);
 
@@ -47,6 +51,7 @@
   }
 
  protected:
+  std::unique_ptr<const ApkAssets> system_assets_;
   std::unique_ptr<const ApkAssets> style_assets_;
   std::unique_ptr<const ApkAssets> libclient_assets_;
   std::unique_ptr<const ApkAssets> lib_one_assets_;
@@ -262,20 +267,30 @@
   EXPECT_EQ(static_cast<uint32_t>(ResTable_typeSpec::SPEC_PUBLIC), flags);
 }
 
-TEST_F(ThemeTest, FailToCopyThemeWithDifferentAssetManager) {
+TEST_F(ThemeTest, OnlyCopySystemThemeWhenAssetManagersDiffer) {
   AssetManager2 assetmanager_one;
-  assetmanager_one.SetApkAssets({style_assets_.get()});
+  assetmanager_one.SetApkAssets({system_assets_.get(), style_assets_.get()});
 
   AssetManager2 assetmanager_two;
-  assetmanager_two.SetApkAssets({style_assets_.get()});
+  assetmanager_two.SetApkAssets({system_assets_.get(), style_assets_.get()});
 
   auto theme_one = assetmanager_one.NewTheme();
   ASSERT_TRUE(theme_one->ApplyStyle(app::R::style::StyleOne));
 
   auto theme_two = assetmanager_two.NewTheme();
+  ASSERT_TRUE(theme_two->ApplyStyle(R::style::Theme_One));
   ASSERT_TRUE(theme_two->ApplyStyle(app::R::style::StyleTwo));
 
-  EXPECT_FALSE(theme_one->SetTo(*theme_two));
+  EXPECT_TRUE(theme_one->SetTo(*theme_two));
+
+  Res_value value;
+  uint32_t flags;
+
+  // No app resources.
+  EXPECT_EQ(kInvalidCookie, theme_one->GetAttribute(app::R::attr::attr_one, &value, &flags));
+
+  // Only system.
+  EXPECT_NE(kInvalidCookie, theme_one->GetAttribute(R::attr::foreground, &value, &flags));
 }
 
 }  // namespace android