refactor: drag and drop files

src/routes/chat/DMList/index.js

@@ -17,16 +17,22 @@ export default function DMList({ uids, setDropFiles }) {
     }
   );
   const sessions = uids.map((uid) => {
-    const mids = userMessage[uid];
+    const mids = userMessage[uid] || [];
+    if (mids.length == 0) {
+      return { lastMid: null, unreads: 0, uid };
+    }
     const lastMid = [...mids].pop();
     const readIndex = readUsers[uid];
     const unreads = getUnreadCount({ mids, readIndex, messageData, loginUid });
 
     return { lastMid, unreads, uid };
   });
-
+  console.log("temp uids", sessions);
   return sessions
-    .sort((s1, s2) => s2.lastMid - s1.lastMid)
+    .sort((s1, s2) => {
+      if (!s1.lastMid) return s2.lastMid - Infinity;
+      return s2.lastMid - s1.lastMid;
+    })
     .map(({ lastMid, uid, unreads }) => {
       return (
         <NavItem