use SizedBox

example/lib/customize_channel_preview.dart

@@ -43,10 +43,7 @@ class ChannelListPage extends StatelessWidget {
                     radius: 10,
                     child: Text(channelClient.state.unreadCount.toString()),
                   )
-                : SizedBox(
-                    height: 0,
-                    width: 0,
-                  ),
+                : SizedBox(),
           );
         },
         sort: [SortOption('last_message_at')],

lib/src/channel_preview.dart

@@ -79,9 +79,7 @@ class ChannelPreview extends StatelessWidget {
     final lastMessage =
         channelState.messages.isNotEmpty ? channelState.messages.last : null;
     if (lastMessage == null) {
-      return SizedBox.fromSize(
-        size: Size.zero,
-      );
+      return SizedBox();
     }
 
     final prefix = lastMessage.attachments

lib/src/message_list_view.dart

@@ -91,9 +91,7 @@ class _MessageListViewState extends State<MessageListView> {
                   );
                 }
               } else {
-                return SizedBox.fromSize(
-                  size: Size.zero,
-                );
+                return SizedBox();
               }
             }
 

lib/src/message_widget.dart

@@ -202,9 +202,7 @@ class _MessageWidgetState extends State<MessageWidget>
                             ),
                           ),
                         )
-                      : SizedBox.fromSize(
-                          size: Size.zero,
-                        ),
+                      : SizedBox(),
                 ],
               ),
               margin: EdgeInsets.only(