From 698b684233c6d50e2eae7fc34001ff4f75e60a57 Mon Sep 17 00:00:00 2001
From: tangjinzhou <415800467@qq.com>
Date: Sun, 5 Dec 2021 00:15:53 +0800
Subject: [PATCH] fix: select cannot scroll #4971 close #4971

---
 components/vc-virtual-list/List.tsx           | 21 +++++++++++++----
 .../vc-virtual-list/hooks/useHeights.tsx      | 23 ++++++++++++-------
 .../vc-virtual-list/hooks/useScrollTo.tsx     |  4 ++--
 3 files changed, 34 insertions(+), 14 deletions(-)

diff --git a/components/vc-virtual-list/List.tsx b/components/vc-virtual-list/List.tsx
index 0644aba21..4d62a39be 100644
--- a/components/vc-virtual-list/List.tsx
+++ b/components/vc-virtual-list/List.tsx
@@ -148,7 +148,12 @@ const List = defineComponent({
     }
 
     // ================================ Height ================================
-    const [setInstance, collectHeight, heights] = useHeights(getKey, null, null);
+    const [setInstance, collectHeight, heights, updatedMark] = useHeights(
+      mergedData,
+      getKey,
+      null,
+      null,
+    );
 
     const calRes = ref<{
       scrollHeight?: number;
@@ -157,9 +162,17 @@ const List = defineComponent({
       offset?: number;
     }>({});
     watch(
-      [inVirtual, useVirtual, () => state.scrollTop, mergedData, heights, () => props.height],
+      [
+        inVirtual,
+        useVirtual,
+        () => state.scrollTop,
+        mergedData,
+        updatedMark,
+        heights,
+        () => props.height,
+      ],
       () => {
-        nextTick(() => {
+        setTimeout(() => {
           if (!useVirtual.value) {
             calRes.value = {
               scrollHeight: undefined,
@@ -191,7 +204,7 @@ const List = defineComponent({
             const item = data[i];
             const key = getKey(item);
 
-            const cacheHeight = heights[key];
+            const cacheHeight = heights.value[key];
             const currentItemBottom =
               itemTop + (cacheHeight === undefined ? props.itemHeight! : cacheHeight);
 
diff --git a/components/vc-virtual-list/hooks/useHeights.tsx b/components/vc-virtual-list/hooks/useHeights.tsx
index f84d07f66..70bdca9f8 100644
--- a/components/vc-virtual-list/hooks/useHeights.tsx
+++ b/components/vc-virtual-list/hooks/useHeights.tsx
@@ -1,16 +1,22 @@
-import type { VNodeProps } from 'vue';
-import { reactive } from 'vue';
+import type { VNodeProps, ComputedRef, Ref } from 'vue';
+import { shallowRef, watch, ref } from 'vue';
 import type { GetKey } from '../interface';
 
-type CacheMap = Record<string, number>;
+type CacheMap = Ref<Record<string, number>>;
 
 export default function useHeights<T>(
+  mergedData: ComputedRef<any[]>,
   getKey: GetKey<T>,
   onItemAdd?: ((item: T) => void) | null,
   onItemRemove?: ((item: T) => void) | null,
-): [(item: T, instance: HTMLElement) => void, () => void, CacheMap] {
+): [(item: T, instance: HTMLElement) => void, () => void, CacheMap, Ref<Symbol>] {
   const instance = new Map<VNodeProps['key'], HTMLElement>();
-  const heights = reactive({});
+  const heights = shallowRef({});
+  const updatedMark = ref(Symbol('update'));
+  watch(mergedData, () => {
+    heights.value = {};
+    updatedMark.value = Symbol('update');
+  });
   let heightUpdateId = 0;
   function collectHeight() {
     heightUpdateId += 1;
@@ -22,9 +28,10 @@ export default function useHeights<T>(
       instance.forEach((element, key) => {
         if (element && element.offsetParent) {
           const { offsetHeight } = element;
-          if (heights[key!] !== offsetHeight) {
+          if (heights.value[key!] !== offsetHeight) {
             //changed = true;
-            heights[key!] = element.offsetHeight;
+            updatedMark.value = Symbol('update');
+            heights.value[key!] = element.offsetHeight;
           }
         }
       });
@@ -52,5 +59,5 @@ export default function useHeights<T>(
     }
   }
 
-  return [setInstance, collectHeight, heights];
+  return [setInstance, collectHeight, heights, updatedMark];
 }
diff --git a/components/vc-virtual-list/hooks/useScrollTo.tsx b/components/vc-virtual-list/hooks/useScrollTo.tsx
index aab63b933..bfd372917 100644
--- a/components/vc-virtual-list/hooks/useScrollTo.tsx
+++ b/components/vc-virtual-list/hooks/useScrollTo.tsx
@@ -7,7 +7,7 @@ import type { GetKey } from '../interface';
 export default function useScrollTo(
   containerRef: Ref<Element | undefined>,
   mergedData: ComputedRef<any[]>,
-  heights: Data,
+  heights: Ref<Data>,
   props,
   getKey: GetKey,
   collectHeight: () => void,
@@ -63,7 +63,7 @@ export default function useScrollTo(
           for (let i = 0; i <= maxLen; i += 1) {
             const key = getKey(data[i]);
             itemTop = stackTop;
-            const cacheHeight = heights[key!];
+            const cacheHeight = heights.value[key!];
             itemBottom = itemTop + (cacheHeight === undefined ? itemHeight : cacheHeight);
 
             stackTop = itemBottom;