From 54a08a254cef736799c81e62397693ece192fc2d Mon Sep 17 00:00:00 2001
From: Gildas Garcia <1122076+djhi@users.noreply.github.com>
Date: Mon, 15 Feb 2021 11:03:42 +0100
Subject: [PATCH] Apply review

---
 .../src/form/FormTabHeader.tsx                | 22 ++++++++++++-------
 packages/ra-ui-materialui/src/form/index.tsx  |  1 +
 2 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/packages/ra-ui-materialui/src/form/FormTabHeader.tsx b/packages/ra-ui-materialui/src/form/FormTabHeader.tsx
index 28ab29d5672..9cb30a68543 100644
--- a/packages/ra-ui-materialui/src/form/FormTabHeader.tsx
+++ b/packages/ra-ui-materialui/src/form/FormTabHeader.tsx
@@ -1,4 +1,5 @@
 import * as React from 'react';
+import { useEffect } from 'react';
 import { Link, useLocation } from 'react-router-dom';
 import MuiTab from '@material-ui/core/Tab';
 import classnames from 'classnames';
@@ -18,14 +19,19 @@ export const FormTabHeader = ({
     const formGroup = useFormGroup(value);
     const form = useForm();
     const [showError, setShowError] = React.useState(false);
-    form.subscribe(
-        state => {
-            if (!showError && (state.submitting || state.submitFailed)) {
-                setShowError(true);
-            }
-        },
-        { submitting: true, submitFailed: true }
-    );
+
+    useEffect(() => {
+        const unsubscribe = form.subscribe(
+            state => {
+                if (!showError && (state.submitting || state.submitFailed)) {
+                    setShowError(true);
+                }
+            },
+            { submitting: true, submitFailed: true }
+        );
+
+        return unsubscribe;
+    }, [form, showError]);
 
     return (
         <MuiTab
diff --git a/packages/ra-ui-materialui/src/form/index.tsx b/packages/ra-ui-materialui/src/form/index.tsx
index a49cfb557e7..853e21d7c98 100644
--- a/packages/ra-ui-materialui/src/form/index.tsx
+++ b/packages/ra-ui-materialui/src/form/index.tsx
@@ -8,6 +8,7 @@ import TabbedForm, { TabbedFormProps } from './TabbedForm';
 import TabbedFormTabs from './TabbedFormTabs';
 import Toolbar, { ToolbarProps } from './Toolbar';
 import getFormInitialValues from './getFormInitialValues';
+export * from './FormTabHeader';
 
 export type {
     SimpleFormProps,