diff --git a/src/com/android/launcher3/model/BaseLoaderResults.java b/src/com/android/launcher3/model/BaseLoaderResults.java
index 6c4cfb9..b50ab58 100644
--- a/src/com/android/launcher3/model/BaseLoaderResults.java
+++ b/src/com/android/launcher3/model/BaseLoaderResults.java
@@ -43,6 +43,7 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Objects;
 import java.util.concurrent.Executor;
 
 /**
@@ -203,7 +204,9 @@
         }
 
         private void bind() {
-            IntSet currentScreenIds = mCallbacks.getPagesToBindSynchronously(mOrderedScreenIds);
+            final IntSet currentScreenIds =
+                    mCallbacks.getPagesToBindSynchronously(mOrderedScreenIds);
+            Objects.requireNonNull(currentScreenIds, "Null screen ids provided by " + mCallbacks);
 
             // Separate the items that are on the current screen, and all the other remaining items
             ArrayList<ItemInfo> currentWorkspaceItems = new ArrayList<>();
diff --git a/src/com/android/launcher3/model/BgDataModel.java b/src/com/android/launcher3/model/BgDataModel.java
index d52537e..de23c4b 100644
--- a/src/com/android/launcher3/model/BgDataModel.java
+++ b/src/com/android/launcher3/model/BgDataModel.java
@@ -31,6 +31,7 @@
 import android.util.ArraySet;
 import android.util.Log;
 
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
 import com.android.launcher3.LauncherSettings;
@@ -469,6 +470,7 @@
          * or an empty IntSet
          * @param orderedScreenIds All the page ids to be bound
          */
+        @NonNull
         default IntSet getPagesToBindSynchronously(IntArray orderedScreenIds) {
             return new IntSet();
         }
diff --git a/src/com/android/launcher3/model/ModelUtils.java b/src/com/android/launcher3/model/ModelUtils.java
index df6768d..422af43 100644
--- a/src/com/android/launcher3/model/ModelUtils.java
+++ b/src/com/android/launcher3/model/ModelUtils.java
@@ -51,7 +51,7 @@
      * specified screen.
      */
     public static <T extends ItemInfo> void filterCurrentWorkspaceItems(
-            IntSet currentScreenIds,
+            final IntSet currentScreenIds,
             ArrayList<T> allWorkspaceItems,
             ArrayList<T> currentScreenItems,
             ArrayList<T> otherScreenItems) {