feat: Added new picker implementation

lib/src/message_input.dart

@@ -839,9 +839,25 @@ class MessageInputState extends State<MessageInput> {
               }
 
               if (snapshot.data) {
-                return IgnorePointer(
+                if (_attachmentContainsFile) {
-                  ignoring: _attachmentContainsFile,
+                  return Container(
-                  child: MediaListView(
+                    color: Color(0xfff2f2f2),
+                    child: InkWell(
+                      onTap: () {
+                        pickFile(DefaultAttachmentTypes.file);
+                      },
+                      child: Text(
+                        'Add more files',
+                        style: TextStyle(
+                          color: StreamChatTheme.of(context).accentColor,
+                          fontWeight: FontWeight.bold,
+                        ),
+                      ),
+                    ),
+                    alignment: Alignment.center,
+                  );
+                }
+                return MediaListView(
                   selectedIds: _attachments.map((e) => e.id).toList(),
                   onSelect: (media) async {
                     if (!_attachments
@@ -854,7 +870,6 @@ class MessageInputState extends State<MessageInput> {
                       });
                     }
                   },
-                  ),
                 );
               }