added ReadingContainer

lib/screens/metering/components/topbar/components/reading_container.dart

@@ -0,0 +1,71 @@
+import 'package:flutter/material.dart';
+import 'package:lightmeter/res/dimens.dart';
+
+class ReadingValue {
+  final String label;
+  final String value;
+
+  const ReadingValue({
+    required this.label,
+    required this.value,
+  });
+}
+
+class ReadingContainer extends StatelessWidget {
+  final List<_ReadingValueBuilder> _items;
+
+  ReadingContainer({
+    required List<ReadingValue> values,
+    super.key,
+  }) : _items = values.map((e) => _ReadingValueBuilder(e)).toList();
+
+  ReadingContainer.singleValue({
+    required ReadingValue value,
+    super.key,
+  }) : _items = [_ReadingValueBuilder(value)];
+
+  @override
+  Widget build(BuildContext context) {
+    return ClipRRect(
+      borderRadius: BorderRadius.circular(Dimens.borderRadiusM),
+      child: ColoredBox(
+        color: Theme.of(context).colorScheme.primaryContainer,
+        child: Padding(
+          padding: const EdgeInsets.all(Dimens.paddingM),
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.start,
+            mainAxisAlignment: MainAxisAlignment.spaceBetween,
+            mainAxisSize: MainAxisSize.min,
+            children: _items,
+          ),
+        ),
+      ),
+    );
+  }
+}
+
+class _ReadingValueBuilder extends StatelessWidget {
+  final ReadingValue reading;
+
+  const _ReadingValueBuilder(this.reading);
+
+  @override
+  Widget build(BuildContext context) {
+    final textTheme = Theme.of(context).textTheme;
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      mainAxisSize: MainAxisSize.min,
+      children: [
+        Text(
+          reading.label,
+          style: textTheme.labelLarge?.copyWith(color: Theme.of(context).colorScheme.onPrimaryContainer),
+        ),
+        const SizedBox(height: Dimens.grid8),
+        Text(
+          reading.value,
+          style: textTheme.titleLarge?.copyWith(color: Theme.of(context).colorScheme.onPrimaryContainer),
+        ),
+      ],
+    );
+  }
+}