pinafore/routes/_components/VirtualListItem.html
2018-01-16 18:08:37 -08:00

42 lines
1.1 KiB
HTML

<div class="virtual-list-item"
ref:node
style="transform: translate3d(0, {{offset}}px, 0);"
>
<:Component {component} virtualProps="{{props}}" />
</div>
<style>
.virtual-list-item {
position: absolute;
top: 0;
}
</style>
<script>
import { virtualListStore } from '../_utils/virtualListStore'
let updateItemHeights = {}
let promise = Promise.resolve()
export default {
oncreate() {
let key = this.get('key')
updateItemHeights[key] = this.refs.node.offsetHeight
promise.then(() => {
// update all item heights in one microtask batch for better perf
let updatedKeys = Object.keys(updateItemHeights)
if (!updatedKeys.length) {
return
}
// batch all updates to itemHeights for better perf
let itemHeights = this.store.get('itemHeights')
for (key of updatedKeys) {
itemHeights[key] = updateItemHeights[key]
}
this.store.set({
itemHeights: itemHeights
})
updateItemHeights = {}
})
},
store: () => virtualListStore
}
</script>