feat:增加加载中显示

lib/widget/common.dart

@@ -33,4 +33,23 @@ Widget circleIconButton({
     ),
     child: Icon(icon, color: Colors.white),
   );
-}
+}
+
+Widget buildErrorInfo({
+  required String errorInfo,
+  required VoidCallback onPressed,
+}) {
+  return Center(
+    child: Column(
+      mainAxisAlignment: MainAxisAlignment.center,
+      children: [
+        Text('加载失败: $errorInfo'),
+        ElevatedButton(onPressed: onPressed, child: Text('重试')),
+      ],
+    ),
+  );
+}
+
+Widget buildLoadingIndicator() {
+  return Center(child: CircularProgressIndicator());
+}