备份前删除原备份

mobile/src/main/java/cn/garymb/ygomobile/ui/cards/DeckManagerFragment.java

@@ -1188,6 +1188,7 @@ public class DeckManagerFragment extends BaseFragemnt implements RecyclerViewIte
     }
 
     private void doBackUpDeck() {
+        FileUtils.delFile(ORI_DECK);//备份前删除原备份
         try {
             FileUtils.copyDir(mSettings.getDeckDir(), ORI_DECK, true);
             File ydks = new File(ORI_DECK);