add all frontend files

node_modules/rc-virtual-list/es/hooks/useChildren.js

@@ -0,0 +1,21 @@
+import * as React from 'react';
+import { Item } from "../Item";
+export default function useChildren(list, startIndex, endIndex, scrollWidth, offsetX, setNodeRef, renderFunc, _ref) {
+  var getKey = _ref.getKey;
+  return list.slice(startIndex, endIndex + 1).map(function (item, index) {
+    var eleIndex = startIndex + index;
+    var node = renderFunc(item, eleIndex, {
+      style: {
+        width: scrollWidth
+      },
+      offsetX: offsetX
+    });
+    var key = getKey(item);
+    return /*#__PURE__*/React.createElement(Item, {
+      key: key,
+      setRef: function setRef(ele) {
+        return setNodeRef(item, ele);
+      }
+    }, node);
+  });
+}