fix:修复返回上一曲会-1异常问题

app/src/main/java/com/yutou/nas_music_player/containers/MusicContainer.java

@@ -363,6 +363,9 @@ public class MusicContainer {
             tmpList.remove(0);
             return;
         }
+        if (playIndex < 0 || playIndex > playList.size()) {
+            playIndex = 0;
+        }
         switch (playModel) {
             case PLAY_MODEL_ORDER:
                 playOrder(false);
@@ -384,6 +387,9 @@ public class MusicContainer {
      */
     public void playPrevious() {
         playIndex--;
+        if(playIndex<0){
+            playIndex=0;
+        }
         MusicData data = previousPlayerList.getMusicData();
         if (data != null) {
             play(data);