outsource inputfields, added input validation onChange

lib/widgets/ExpandedNumberInputWidget.dart

@@ -0,0 +1,42 @@
+
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+
+class ExpandedNumberInputWidget extends StatelessWidget {
+
+  String _labelDisplayText = "";
+  String _hintText = "";
+  void Function(double) _setValue = (x) => {};
+
+  ExpandedNumberInputWidget(String labelDisplayText, String hintText, void Function(double) setValue, {super.key}) {
+    _labelDisplayText = labelDisplayText;
+    _hintText = hintText;
+    _setValue = setValue;
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Expanded(
+        child: TextFormField(
+          keyboardType: TextInputType.number,
+          inputFormatters: [FilteringTextInputFormatter.allow(RegExp('[0-9.]'))],
+          onChanged: (value) {
+            double? number = double.tryParse(value);
+            if (number == null){
+              ScaffoldMessenger.of(context).showSnackBar(
+                const SnackBar(content: Text('Bitte eine gültige Zahl eingeben')),
+              );
+            }else{
+              ScaffoldMessenger.of(context).hideCurrentSnackBar();
+              _setValue(number);
+            }
+          },
+          decoration: InputDecoration(
+              labelText: _labelDisplayText,
+              hintText: _hintText,
+          ),
+        )
+    );
+  }
+
+}

lib/widgets/MyInputWidget.dart

@@ -1,14 +1,14 @@
-import 'package:energy_bilance/models/EnergyBilanceModel.dart';
+import 'package:energy_bilance/widgets/ExpandedNumberInputWidget.dart';
 import 'package:flutter/material.dart';
-import 'package:flutter/services.dart';
 import 'package:provider/provider.dart';
 
+import '../models/EnergyBilanceModel.dart';
+
 class MyInputWidget extends StatelessWidget {
   const MyInputWidget({super.key});
 
   @override
   Widget build(BuildContext context) {
-
     final model = Provider.of<EnergyBilanceModel>(context);
 
     return Column(
@@ -16,46 +16,9 @@ class MyInputWidget extends StatelessWidget {
             Row(
               mainAxisSize: MainAxisSize.min,
               mainAxisAlignment: MainAxisAlignment.start,
-
               children: [
-                Expanded(
+                ExpandedNumberInputWidget("Anfangsgeschwindigkeit", "in m/s", model.setStartVelocity),
-                    child: TextFormField(
+                ExpandedNumberInputWidget("Endgeschwindigkeit", "in m/s", model.setEndVelocity)
-                      keyboardType: TextInputType.number,
-                      inputFormatters: [FilteringTextInputFormatter.allow(RegExp('[0-9.]'))],
-                      onChanged: (value) {
-                        double number = double.parse(value);
-                        model.setStartVelocity(number);
-                      },
-                      validator: (value) {
-                        if(value == null){
-                          return null;
-                        }
-                        final number = num.tryParse(value);
-                        if(number == null){
-                          return '"$value" ist keine Zahl';
-                        }
-                        return null;
-                      },
-                      decoration: const InputDecoration(
-                          labelText: 'Anfangsgeschwindigkeit',
-                          hintText: 'in m/s'
-                      ),
-                    )
-                ),
-                Expanded(
-                    child: TextFormField(
-                      keyboardType: TextInputType.number,
-                      inputFormatters: [FilteringTextInputFormatter.allow(RegExp('[0-9.]'))],
-                      onChanged: (value) {
-                        double number = double.parse(value);
-                        model.setEndVelocity(number);
-                      },
-                      decoration: const InputDecoration(
-                          labelText: 'Endgeschwindigkeit',
-                          hintText: 'in m/s'
-                      ),
-                    )
-                ),
             ],
           ),
             Row(
@@ -63,53 +26,11 @@ class MyInputWidget extends StatelessWidget {
               mainAxisAlignment: MainAxisAlignment.spaceBetween,
 
               children: [
-                Expanded(
+                ExpandedNumberInputWidget("Anfangshöhe", "in m", model.setStartHeight),
-                    child: TextFormField(
+                ExpandedNumberInputWidget("Endhöhe", "in m", model.setEndHeight),
-                      keyboardType: TextInputType.number,
-                      inputFormatters: [FilteringTextInputFormatter.allow(RegExp('[0-9.]'))],
-                      onChanged: (value) {
-                        double number = double.parse(value);
-                        model.setStartHeight(number);
-                      },
-                      decoration: const InputDecoration(
-                          labelText: 'Anfangshöhe',
-                          hintText: 'in m'
-                      ),
-                    )
-                ),
-                Expanded(
-                    child: TextFormField(
-                      keyboardType: TextInputType.number,
-                      inputFormatters: [FilteringTextInputFormatter.allow(RegExp('[0-9.]'))],
-                      onChanged: (value) {
-                        double number = double.parse(value);
-                        model.setEndHeight(number);
-                      },
-                      decoration: const InputDecoration(
-                          labelText: 'Endhöhe',
-                          hintText: 'in m'
-                      ),
-                    )
-                ),
               ],
             ),
-            Expanded(
+            ExpandedNumberInputWidget("Gewicht", "in kg", model.setWeight),
-                child: TextFormField(
-                  keyboardType: TextInputType.number,
-                  inputFormatters: [FilteringTextInputFormatter.allow(RegExp('[0-9.]'))],
-                  onChanged: (value) {
-                    double? number = double.tryParse(value);
-                    if(number != null){
-                      model.setWeight(number);
-                    }
-                  },
-                  decoration: const InputDecoration(
-                      labelText: 'Gewicht',
-                      hintText: 'in kg'
-                  ),
-                )
-            ),
-
       ]
       );