display spinner on pagination request

js/actions/piece_list_actions.js

@@ -14,6 +14,21 @@ class PieceListActions {
     }
 
     fetchPieceList(page, pageSize, search, orderBy, orderAsc) {
+        // To prevent flickering on a pagination request,
+        // we overwrite the piecelist with an empty list before
+        // pieceListCount === -1 defines the loading state
+        this.actions.updatePieceList({
+            page,
+            pageSize,
+            search,
+            orderBy,
+            orderAsc,
+            'pieceList': [],
+            'pieceListCount': -1
+        });
+
+        // afterwards, we can load the list
+
         return new Promise((resolve, reject) => {
             PieceListFetcher
                 .fetch(page, pageSize, search, orderBy, orderAsc)

js/stores/piece_list_store.js

@@ -19,6 +19,7 @@ class PieceListStore {
          * the number of items the resource actually - without pagination - provides.
          */
         this.pieceList = [];
+        // -1 specifies that the store is currently loading
         this.pieceListCount = -1;
         this.page = 1;
         this.pageSize = 10;