Added Focusnodes in form sample (#707)

form_app/lib/src/autofill.dart

@@ -31,6 +31,8 @@ class _AutofillDemoState extends State<AutofillDemo> {
                   ...[
                     Text('This sample demonstrates autofill. '),
                     TextFormField(
+                      autofocus: true,
+                      textInputAction: TextInputAction.next,
                       decoration: InputDecoration(
                         hintText: 'Jane',
                         labelText: 'First Name',
@@ -38,6 +40,7 @@ class _AutofillDemoState extends State<AutofillDemo> {
                       autofillHints: [AutofillHints.givenName],
                     ),
                     TextFormField(
+                      textInputAction: TextInputAction.next,
                       decoration: InputDecoration(
                         hintText: 'Doe',
                         labelText: 'Last Name',
@@ -46,6 +49,7 @@ class _AutofillDemoState extends State<AutofillDemo> {
                     ),
                     TextField(
                       keyboardType: TextInputType.emailAddress,
+                      textInputAction: TextInputAction.next,
                       decoration: InputDecoration(
                         hintText: 'foo@example.com',
                         labelText: 'Email',
@@ -54,6 +58,7 @@ class _AutofillDemoState extends State<AutofillDemo> {
                     ),
                     TextField(
                       keyboardType: TextInputType.phone,
+                      textInputAction: TextInputAction.next,
                       decoration: InputDecoration(
                         hintText: '(123) 456-7890',
                         labelText: 'Telephone',
@@ -62,6 +67,7 @@ class _AutofillDemoState extends State<AutofillDemo> {
                     ),
                     TextField(
                       keyboardType: TextInputType.streetAddress,
+                      textInputAction: TextInputAction.next,
                       decoration: InputDecoration(
                         hintText: '123 4th Ave',
                         labelText: 'Street Address',
@@ -70,6 +76,7 @@ class _AutofillDemoState extends State<AutofillDemo> {
                     ),
                     TextField(
                       keyboardType: TextInputType.number,
+                      textInputAction: TextInputAction.next,
                       decoration: InputDecoration(
                         hintText: '12345',
                         labelText: 'Postal Code',
@@ -77,6 +84,7 @@ class _AutofillDemoState extends State<AutofillDemo> {
                       autofillHints: <String>[AutofillHints.postalCode],
                     ),
                     TextField(
+                      textInputAction: TextInputAction.next,
                       decoration: InputDecoration(
                         hintText: 'United States',
                         labelText: 'Country',

form_app/lib/src/sign_in_http.dart

@@ -54,6 +54,8 @@ class _SignInHttpDemoState extends State<SignInHttpDemo> {
               children: [
                 ...[
                   TextFormField(
+                    autofocus:  true,
+                    textInputAction: TextInputAction.next,
                     decoration: InputDecoration(
                       filled: true,
                       hintText: 'Your email address',

form_app/lib/src/validation.dart

@@ -64,6 +64,8 @@ class _FormValidationDemoState extends State<FormValidationDemo> {
               children: [
                 // A text field that validates that the text is an adjective.
                 TextFormField(
+                  autofocus: true,
+                  textInputAction: TextInputAction.next,
                   validator: (value) {
                     if (value.isEmpty) {
                       return 'Please enter an adjective.';