初始化

lib/widgets/common/preview/file_previewer.dart

@@ -0,0 +1,61 @@
+import 'package:cached_network_image/cached_network_image.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_cached_pdfview/flutter_cached_pdfview.dart';
+import 'package:go_router/go_router.dart';
+
+void showFilePreviewer(
+  BuildContext context, {
+  required String url,
+}) {
+  showDialog(
+    context: context,
+    builder: (BuildContext context) {
+      return FilePreviewer(
+        url: url,
+      );
+    },
+  );
+}
+
+class FilePreviewer extends StatelessWidget {
+  final String url;
+
+  const FilePreviewer({super.key, this.url = ""});
+
+  bool _isImage(String suffix) {
+    final lower = suffix.toLowerCase();
+    return ['jpg', 'jpeg', 'png', 'gif', 'webp'].contains(lower);
+  }
+
+  bool _isPdf(String suffix) {
+    return suffix.toLowerCase() == 'pdf';
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final suffix = url.split('.').last;
+    Widget child;
+
+    if (_isImage(suffix)) {
+      child = InteractiveViewer(
+        child: CachedNetworkImage(
+          imageUrl: url,
+        ),
+      );
+    } else if (_isPdf(suffix)) {
+      child = PDF(
+        enableSwipe: true,
+      ).cachedFromUrl(url);
+    } else {
+      child = const Text('不支持的文件类型');
+    }
+    return GestureDetector(
+      onTap: () {
+        context.pop();
+      },
+      child: Container(
+        child: child,
+      ),
+    );
+  }
+}