1、优化MyScrollView横向铺满全屏

lib/widget/my_scroll_view.dart

@@ -37,9 +37,12 @@ class MyScrollView extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    Widget contents = Column(
-      crossAxisAlignment: crossAxisAlignment,
-      children: children,
+    Widget contents = SizedBox(
+      width: double.infinity,
+      child: Column(
+        crossAxisAlignment: crossAxisAlignment,
+        children: children,
+      ),
     );
 
     if (defaultTargetPlatform == TargetPlatform.iOS && keyboardConfig != null) {