From 00fd6fbf73c0adf4cf0f1270c16962319af93722 Mon Sep 17 00:00:00 2001
From: Martin Pengelly-Phillips <dev@thisbeyond.com>
Date: Fri, 9 Aug 2024 22:10:39 +0100
Subject: [PATCH] Improve Solid adapter.

Use `createEffect` to ensure scrollElement ref is connected to DOM
and ownerDocument/window before attempting to update measurements
for it. Otherwise, `virtualizer.targetWindow` will be set to null
(in _willUpdate), the scrollElement rect to nothing and no items
will be displayed.

In addition, remove some logic that causes redundant work to be
done (e.g. `setOptions` called multiple times, `_willUpdate`
called on mount which is a no-op if the scollElement didn't change). Instead rely on the options reactivity to perform the
bulk of the work.

Also, reset virtual items store when options change to ensure that
reactivity is maintained - e.g. so that `measureItem` is called
again in a `<For>` loop if `scrollMargin` changed.
---
 packages/solid-virtual/src/index.tsx | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/packages/solid-virtual/src/index.tsx b/packages/solid-virtual/src/index.tsx
index 69ac34fd..15c2546b 100644
--- a/packages/solid-virtual/src/index.tsx
+++ b/packages/solid-virtual/src/index.tsx
@@ -9,7 +9,7 @@ import {
 } from '@tanstack/virtual-core'
 
 import {
-  createComputed,
+  createEffect,
   createSignal,
   mergeProps,
   onCleanup,
@@ -55,22 +55,19 @@ function createVirtualizerBase<
   }
 
   const virtualizer = new Proxy(instance, handler)
-  virtualizer.setOptions(resolvedOptions)
 
   onMount(() => {
     const cleanup = virtualizer._didMount()
-    virtualizer._willUpdate()
     onCleanup(cleanup)
   })
 
-  createComputed(() => {
+  createEffect(() => {
     virtualizer.setOptions(
       mergeProps(resolvedOptions, options, {
         onChange: (
           instance: Virtualizer<TScrollElement, TItemElement>,
           sync: boolean,
         ) => {
-          instance._willUpdate()
           setVirtualItems(
             reconcile(instance.getVirtualItems(), {
               key: 'index',
@@ -81,6 +78,8 @@ function createVirtualizerBase<
         },
       }),
     )
+    setVirtualItems([])
+    virtualizer._willUpdate()
     virtualizer.measure()
   })