fix download image

packages/stream_chat_flutter/lib/src/attachment_actions_modal.dart

@@ -120,7 +120,7 @@ class AttachmentActionsModal extends StatelessWidget {
                             received,
                           );
                         },
-                      ).catchError((_) {
+                      ).catchError((e, stk) {
                         progressNotifier.value = null;
                       });
 
@@ -225,16 +225,14 @@ class AttachmentActionsModal extends StatelessWidget {
     ValueNotifier<_DownloadProgress?> progressNotifier,
   ) {
     final theme = StreamChatTheme.of(context);
-    return WillPopScope(
-      onWillPop: () => Future.value(false),
-      child: ValueListenableBuilder(
+    return ValueListenableBuilder(
       valueListenable: progressNotifier,
       builder: (_, _DownloadProgress? progress, __) {
         // Pop the dialog in case the progress is null or it's completed.
         if (progress == null || progress.toProgressIndicatorValue == 1.0) {
           Future.delayed(
             const Duration(milliseconds: 500),
-              Navigator.of(context).maybePop,
+            () => Navigator.of(context).maybePop(),
           );
         }
         return Material(
@@ -294,7 +292,6 @@ class AttachmentActionsModal extends StatelessWidget {
           ),
         );
       },
-      ),
     );
   }
 
@@ -310,7 +307,7 @@ class AttachmentActionsModal extends StatelessWidget {
         final contentType = responseHeaders[Headers.contentTypeHeader]!;
         final mimeType = contentType.first.split('/').last;
         filePath ??= '${appDocDir.path}/${attachment.id}.$mimeType';
-        return filePath;
+        return filePath!;
       },
       onReceiveProgress: progressCallback,
     );