[FORM] Form handlers can define an initial value for inputs

Author: darionco

package/pheno_ui/lib/tools/figma_form_handler.dart

@@ -6,6 +6,7 @@ import 'figma_user_data.dart';
 abstract class FigmaFormHandler {
   const FigmaFormHandler();
   bool shouldDisplayInput(String id) => true;
+  Future<T?> initialValueForInputID<T>(BuildContext context, Map<String, FigmaFormInput> inputs, String id) async => null;
   void onInputRegistered<T>(BuildContext context, Map<String, FigmaFormInput> inputs, FigmaFormInput<T> input) { /* nothing */ }
   void onInputValueChanged<T>(BuildContext context, Map<String, FigmaFormInput> inputs, FigmaFormInput<T> input) { /* nothing */ }
   void onInputEditingComplete<T>(BuildContext context, Map<String, FigmaFormInput> inputs, FigmaFormInput<T> input) { /* nothing */ }

package/pheno_ui/lib/widgets/figma_checkbox.dart

@@ -21,6 +21,7 @@ class FigmaCheckboxState extends FigmaComponentState {
   FigmaFormState? form;
   FocusNode? focusNode;
   String _state = 'unchecked';
+  bool _hasInitialValue = false;
   late final String _id = userData.get('id', context: context, listen: false);
 
   bool get checked => _state == 'checked';
@@ -37,7 +38,11 @@ class FigmaCheckboxState extends FigmaComponentState {
     super.initState();
     form = FigmaForm.maybeOf(context);
     if (form != null) {
-      focusNode = form!.registerInput(_id, checked);
+      form!.registerInput(_id, checked).then((value) {
+        focusNode = value.$1;
+        checked = value.$2;
+        _hasInitialValue = true;
+      });
     }
   }
 
@@ -48,6 +53,10 @@ class FigmaCheckboxState extends FigmaComponentState {
 
   @override
   Widget buildFigmaNode(BuildContext context) {
+    if (!_hasInitialValue) {
+      return const SizedBox();
+    }
+
     return GestureDetector(
       onTap: () {
         checked = !checked;

package/pheno_ui/lib/widgets/figma_form.dart

@@ -79,14 +79,17 @@ class FigmaFormState extends StatefulFigmaNodeState<FigmaForm> {
     return handler.shouldDisplayInput(id) ?? true;
   }
 
-  FocusNode registerInput<T>(String id, T initialValue) {
+  Future<(FocusNode, T)> registerInput<T>(String id, T initialValue) async {
     if (inputs.containsKey(id)) {
       logger.w('Input with id $id already exists.');
     }
     FocusNode node = FocusNode();
-    inputs[id] = FigmaFormInput<T>(node, id, initialValue);
-    handler.onInputRegistered(context, inputs, inputs[id]!);
-    return node;
+    T value = await handler.initialValueForInputID<T>(context, inputs, id) ?? initialValue;
+    inputs[id] = FigmaFormInput<T>(node, id, value);
+    if (context.mounted && mounted) {
+      handler.onInputRegistered(context, inputs, inputs[id]!);
+    }
+    return (node, value);
   }
 
   void inputValueChanged<T>(String id, T value) {

package/pheno_ui/lib/widgets/figma_text_field.dart

@@ -1,3 +1,4 @@
+import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 
 import '../models/figma_text_model.dart';
@@ -21,19 +22,29 @@ class FigmaTextField extends StatefulFigmaNode<FigmaTextModel> with FigmaFormWid
 class FigmaTextFieldState extends StatefulFigmaNodeState<FigmaTextField> {
   FigmaFormState? form;
   FocusNode? focusNode;
+  bool _hasInitialValue = false;
+  final TextEditingController _controller = TextEditingController();
   late final String _id = widget.model.userData.get('id', context: context, listen: false);
 
   @override
   void initState() {
     super.initState();
     form = FigmaForm.maybeOf(context);
     if (form != null) {
-      focusNode = form!.registerInput(_id, '');
+      form!.registerInput(_id, '').then((value) {
+        focusNode = value.$1;
+        _controller.text = value.$2;
+        _hasInitialValue = true;
+      });
     }
   }
 
   @override
   Widget buildFigmaNode(BuildContext context) {
+    if (!_hasInitialValue) {
+      return const SizedBox();
+    }
+
     var modelSegments = FigmaText.textSegmentsFromModel(context, widget.model);
     List<TextSpan> segments = modelSegments.map((m) => m.span).toList();
 
@@ -54,6 +65,7 @@ class FigmaTextFieldState extends StatefulFigmaNodeState<FigmaTextField> {
     return Align(
       alignment: alignment,
       child: TextField(
+        controller: _controller,
         focusNode: focusNode,
         onTapOutside: (_) => focusNode?.unfocus(),
         style: segments[0].style,