1、优化图片加载ImageWidget

lib/widget/image_widget.dart

@@ -17,15 +17,18 @@ class ImageWidget {
     double? height,
     BoxFit fit = BoxFit.cover,
     Widget? placeholder,
+    bool signature = false,
   }) {
     var domainUrl = domain ?? ImageWidget.domain;
     if (url != null && !url.startsWith("http")) {
       url = domainUrl + url;
     }
-    url = url != null && url.isNotEmpty ? "$url?${Random().nextDouble()}" : "";
+    if(signature){
+      url = url != null && url.isNotEmpty ? "$url?${Random().nextDouble()}" : "";
+    }
     return OctoImage(
       // 拼接Random，修复图片地址固定，无法展示最新图片问题
-      image: CachedNetworkImageProvider(url),
+      image: CachedNetworkImageProvider(url ?? ""),
       imageBuilder: MyOctoImageTransformer.getOctoImageBuilder(type),
       errorBuilder: ImageWidget.placeholderBuilder(errorWidget: placeholder),
       fit: fit,