diff --git a/app/src/main/java/helium314/keyboard/latin/utils/ToolbarUtils.kt b/app/src/main/java/helium314/keyboard/latin/utils/ToolbarUtils.kt
index 5420a7b8..dc5a78c6 100644
--- a/app/src/main/java/helium314/keyboard/latin/utils/ToolbarUtils.kt
+++ b/app/src/main/java/helium314/keyboard/latin/utils/ToolbarUtils.kt
@@ -262,14 +262,14 @@ private fun toolbarKeyCustomizer(context: Context, key: ToolbarKey) {
     layout.findViewById<EditText>(R.id.toolbar_key_code)?.apply {
         setText(getCodeForToolbarKey(key).toString())
         doAfterTextChanged {
-            keyCode = it?.toString()
+            keyCode = it?.toString()?.ifEmpty { "0" }
             checkOk()
         }
     }
     layout.findViewById<EditText>(R.id.toolbar_key_longpress_code)?.apply {
         setText(getCodeForToolbarKeyLongClick(key).toString())
         doAfterTextChanged {
-            longpressCode = it?.toString()
+            longpressCode = it?.toString()?.ifEmpty { "0" }
             checkOk()
         }
     }
diff --git a/app/src/main/res/layout/toolbar_key_customizer.xml b/app/src/main/res/layout/toolbar_key_customizer.xml
index 081d0038..9d5149df 100644
--- a/app/src/main/res/layout/toolbar_key_customizer.xml
+++ b/app/src/main/res/layout/toolbar_key_customizer.xml
@@ -18,7 +18,7 @@
             android:id="@+id/toolbar_key_code"
             android:layout_width="0dp"
             android:layout_height="wrap_content"
-            android:inputType="number"
+            android:inputType="numberSigned"
             android:layout_weight="1" />
     </LinearLayout>
     <LinearLayout