Add image selection field which allows picking from gallery or taking a new photo with camera

lib/widget/fields.dart

@@ -1,5 +1,89 @@
 
 import 'package:flutter/material.dart';
+import 'package:font_awesome_flutter/font_awesome_flutter.dart';
+import 'package:image_picker/image_picker.dart';
+
+import 'dart:async';
+import 'dart:io';
+
+// TODO - Perhaps refactor all this using flutter_form_builder - https://pub.dev/packages/flutter_form_builder
+
+
+/*
+ * Form field for selecting an image file,
+ * either from the gallery, or from the camera.
+ */
+class ImagePickerField extends FormField<File> {
+
+  static void _selectFromGallery(FormFieldState<File> field) {
+    _getImageFromGallery(field);
+  }
+
+  static void _selectFromCamera(FormFieldState<File> field) {
+    _getImageFromCamera(field);
+  }
+
+  static Future<void> _getImageFromGallery(FormFieldState<File> field) async {
+    
+    File image;
+    
+    await ImagePicker.pickImage(source: ImageSource.gallery).then((File img) {
+      image = img;
+    });
+
+    field.didChange(image);
+  }
+
+  static Future<void> _getImageFromCamera(FormFieldState<File> field) async {
+    File image;
+
+    await ImagePicker.pickImage(source: ImageSource.camera).then((File img) {
+      image = img;
+    });
+
+    field.didChange(image);
+  }
+
+  ImagePickerField({String label = "Attach Image", Function onSaved, bool required = false}) :
+      super(
+        onSaved: onSaved,
+        validator: (File img) {
+          if (required && (img == null)) {
+            return "Required";
+          }
+
+          return null;
+        },
+        builder: (FormFieldState<File> state) {
+          return InputDecorator(
+            decoration: InputDecoration(
+              errorText: state.errorText,
+              labelText: required ? label + "*" : label,
+            ),
+            child: Row(
+              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+              children: <Widget>[
+                FlatButton(
+                  child: Text("Select Image"),
+                  onPressed: () {
+                    _selectFromGallery(state);
+                  },
+                ),
+                FlatButton(
+                  child: Text("Take Picture"),
+                  onPressed: () {
+                    _selectFromCamera(state);
+                  },
+                )
+              ],
+            ),
+          );
+          return ListTile(
+            title: Text("Select Image"),
+          );
+        }
+      );
+}
 
 
 class CheckBoxField extends FormField<bool> {
@@ -25,7 +109,7 @@ class StringField extends TextFormField {
   StringField({String label, String hint, String initial, Function onSaved, Function validator, bool allowEmpty = false, bool isEnabled = true}) :
       super(
         decoration: InputDecoration(
-          labelText: label,
+          labelText: allowEmpty ? label : label + "*",
           hintText: hint
         ),
         initialValue: initial,