diff --git a/tools/aapt/SdkConstants.h b/tools/aapt/SdkConstants.h
index 04fbbe1..955581c 100644
--- a/tools/aapt/SdkConstants.h
+++ b/tools/aapt/SdkConstants.h
@@ -46,6 +46,7 @@
     SDK_P = 28,
     SDK_Q = 29,
     SDK_R = 30,
+    SDK_S = 31,
 };
 
 #endif // H_AAPT_SDK_CONSTANTS