add two views

lib/helper/input_validators.dart

@@ -0,0 +1,34 @@
+class InputValidators {
+  static double? number(String? value) =>
+      double.tryParse((value ?? '').trim().replaceAll(',', '.'));
+
+  static String? requiredText(String? value) =>
+      value == null || value.trim().isEmpty ? 'Bitte ausfüllen' : null;
+
+  static String? nonNegative(String? value, {bool optional = false}) {
+    if (optional && (value ?? '').trim().isEmpty) return null;
+    final parsed = number(value);
+    return parsed == null || !parsed.isFinite || parsed < 0
+        ? 'Zahl ab 0 eingeben'
+        : null;
+  }
+
+  static String? positive(String? value) {
+    final parsed = number(value);
+    return parsed == null || !parsed.isFinite || parsed <= 0
+        ? 'Zahl größer 0 eingeben'
+        : null;
+  }
+
+  static String? hours(String? value) {
+    final parsed = int.tryParse((value ?? '').trim());
+    return parsed == null || parsed < 0 ? 'Ganze Zahl ab 0 eingeben' : null;
+  }
+
+  static String? minutes(String? value) {
+    final parsed = int.tryParse((value ?? '').trim());
+    return parsed == null || parsed < 0 || parsed > 59
+        ? '0 bis 59 eingeben'
+        : null;
+  }
+}