比较完美完成返回滚动实现

src/store/index.js

@@ -6,6 +6,9 @@ export default createStore({
     // debugStr: "测试debug字符",
     showSongDetail: false, //是否显示歌曲详情
     keywords: "", //查询关键字
+    backSnaps: [], //返回快照
+    lastHistoryPos: -1,
+    lashHistoryLength: 0,
     settings: {
       currentRoute: "/discover/recommend", //当前路由
       songId: 0, //歌曲id
@@ -80,6 +83,21 @@ export default createStore({
       saveLoaclSettings(state.settings);
     },
 
+    //载入backSnaps设置
+    loadBackSnaps(state) {
+      const l = localStorage.getItem("zmusic.backSnaps");
+      if (l) state.backSnaps = { ...state.backSnaps, ...JSON.parse(l) };
+    },
+    //保存backSnaps设置
+    saveBackSnaps(state, backSnaps) {
+      state.backSnaps = { ...state.backSnaps, ...backSnaps };
+      saveLoaclTheme(state.backSnaps);
+    },
+    saveSnaps(state, snap)
+    {
+      // state.backSnaps[snap.idx] = 
+    },
+
     //载入theme设置
     loadTheme(state) {
       const l = localStorage.getItem("zmusic.theme");
@@ -158,3 +176,6 @@ function saveLoaclCaches(s) {
 function saveLoaclTheme(s) {
   localStorage.setItem("zmusic.theme", JSON.stringify(s));
 }
+function saveLoaclBackSnaps(s) {
+  localStorage.setItem("zmusic.backSnaps", JSON.stringify(s));
+}