317 lines
13 KiB
Vue
317 lines
13 KiB
Vue
<template>
|
|
<DocSectionText v-bind="$attrs">
|
|
<p>When lazy loading is enabled via the <i>virtualScrollerOptions</i>, data is fetched on demand during scrolling instead of preload.</p>
|
|
<p>In sample below, an in-memory list and timeout is used to mimic fetching from a remote datasource. The <i>virtualCars</i> is an empty array that is populated on scroll.</p>
|
|
</DocSectionText>
|
|
<DeferredDemo @load="loadDemoData">
|
|
<div class="card">
|
|
<DataTable
|
|
:value="virtualCars"
|
|
scrollable
|
|
scrollHeight="400px"
|
|
:virtualScrollerOptions="{ lazy: true, onLazyLoad: loadCarsLazy, itemSize: 46, delay: 200, showLoader: true, loading: lazyLoading, numToleratedItems: 10 }"
|
|
tableStyle="min-width: 50rem"
|
|
>
|
|
<Column field="id" header="Id" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="60%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="vin" header="Vin" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="40%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="year" header="Year" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="30%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="brand" header="Brand" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="40%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="color" header="Color" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="60%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
</DataTable>
|
|
</div>
|
|
</DeferredDemo>
|
|
<DocSectionCode :code="code" :service="['CarService']" />
|
|
</template>
|
|
|
|
<script>
|
|
import { CarService } from '@/service/CarService';
|
|
|
|
export default {
|
|
data() {
|
|
return {
|
|
cars: null,
|
|
virtualCars: Array.from({ length: 100000 }),
|
|
lazyLoading: false,
|
|
loadLazyTimeout: null,
|
|
code: {
|
|
basic: `
|
|
<DataTable :value="virtualCars" scrollable scrollHeight="400px" tableStyle="min-width: 50rem"
|
|
:virtualScrollerOptions="{ lazy: true, onLazyLoad: loadCarsLazy, itemSize: 46, delay: 200, showLoader: true, loading: lazyLoading, numToleratedItems: 10 }">
|
|
<Column field="id" header="Id" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="60%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="vin" header="Vin" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="40%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="year" header="Year" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="30%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="brand" header="Brand" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="40%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="color" header="Color" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="60%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
</DataTable>
|
|
`,
|
|
options: `
|
|
<template>
|
|
<div class="card">
|
|
<DataTable :value="virtualCars" scrollable scrollHeight="400px" tableStyle="min-width: 50rem"
|
|
:virtualScrollerOptions="{ lazy: true, onLazyLoad: loadCarsLazy, itemSize: 46, delay: 200, showLoader: true, loading: lazyLoading, numToleratedItems: 10 }">
|
|
<Column field="id" header="Id" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="60%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="vin" header="Vin" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="40%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="year" header="Year" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="30%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="brand" header="Brand" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="40%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="color" header="Color" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="60%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
</DataTable>
|
|
</div>
|
|
</template>
|
|
|
|
<script>
|
|
import { CarService } from '@/service/CarService';
|
|
|
|
export default {
|
|
data() {
|
|
return {
|
|
cars: null,
|
|
virtualCars: Array.from({ length: 100000 }),
|
|
lazyLoading: false,
|
|
loadLazyTimeout: null
|
|
};
|
|
},
|
|
mounted() {
|
|
this.cars = Array.from({ length: 100000 }).map((_, i) => CarService.generateCar(i + 1));
|
|
},
|
|
methods: {
|
|
loadCarsLazy(event) {
|
|
!this.lazyLoading && (this.lazyLoading = true);
|
|
|
|
if (this.loadLazyTimeout) {
|
|
clearTimeout(this.loadLazyTimeout);
|
|
}
|
|
|
|
//simulate remote connection with a timeout
|
|
this.loadLazyTimeout = setTimeout(() => {
|
|
let _virtualCars = [...this.virtualCars];
|
|
let { first, last } = event;
|
|
|
|
//load data of required page
|
|
const loadedCars = this.cars.slice(first, last);
|
|
|
|
//populate page of virtual cars
|
|
Array.prototype.splice.apply(_virtualCars, [...[first, last - first], ...loadedCars]);
|
|
|
|
this.virtualCars = _virtualCars;
|
|
this.lazyLoading = false;
|
|
}, Math.random() * 1000 + 250);
|
|
}
|
|
}
|
|
};
|
|
<\/script>
|
|
`,
|
|
composition: `
|
|
<template>
|
|
<div class="card">
|
|
<DataTable :value="virtualCars" scrollable scrollHeight="400px" tableStyle="min-width: 50rem"
|
|
:virtualScrollerOptions="{ lazy: true, onLazyLoad: loadCarsLazy, itemSize: 46, delay: 200, showLoader: true, loading: lazyLoading, numToleratedItems: 10 }">
|
|
<Column field="id" header="Id" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="60%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="vin" header="Vin" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="40%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="year" header="Year" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="30%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="brand" header="Brand" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="40%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
<Column field="color" header="Color" style="width: 20%">
|
|
<template #loading>
|
|
<div class="flex items-center" :style="{ height: '17px', 'flex-grow': '1', overflow: 'hidden' }">
|
|
<Skeleton width="60%" height="1rem" />
|
|
</div>
|
|
</template>
|
|
</Column>
|
|
</DataTable>
|
|
</div>
|
|
</template>
|
|
|
|
<script setup>
|
|
import { ref, onMounted } from 'vue';
|
|
import { CarService } from '@/service/CarService';
|
|
|
|
onMounted(() => {
|
|
cars.value = Array.from({ length: 100000 }).map((_, i) => CarService.generateCar(i + 1));
|
|
});
|
|
|
|
const cars = ref();
|
|
const virtualCars = ref(Array.from({ length: 100000 }));
|
|
const lazyLoading = ref(false);
|
|
const loadLazyTimeout = ref();
|
|
|
|
const loadCarsLazy = (event) => {
|
|
!lazyLoading.value && (lazyLoading.value = true);
|
|
|
|
if (loadLazyTimeout.value) {
|
|
clearTimeout(loadLazyTimeout.value);
|
|
}
|
|
|
|
//simulate remote connection with a timeout
|
|
loadLazyTimeout.value = setTimeout(() => {
|
|
let _virtualCars = [...virtualCars.value];
|
|
let { first, last } = event;
|
|
|
|
//load data of required page
|
|
const loadedCars = cars.value.slice(first, last);
|
|
|
|
//populate page of virtual cars
|
|
Array.prototype.splice.apply(_virtualCars, [...[first, last - first], ...loadedCars]);
|
|
|
|
virtualCars.value = _virtualCars;
|
|
lazyLoading.value = false;
|
|
}, Math.random() * 1000 + 250);
|
|
};
|
|
<\/script>
|
|
`,
|
|
data: `
|
|
{
|
|
id: 1
|
|
vin: tvACo,
|
|
brand: Norma,
|
|
color: Black,
|
|
year: 2002
|
|
}`
|
|
}
|
|
};
|
|
},
|
|
methods: {
|
|
loadDemoData() {
|
|
this.cars = Array.from({ length: 100000 }).map((_, i) => CarService.generateCar(i + 1));
|
|
},
|
|
loadCarsLazy(event) {
|
|
!this.lazyLoading && (this.lazyLoading = true);
|
|
|
|
if (this.loadLazyTimeout) {
|
|
clearTimeout(this.loadLazyTimeout);
|
|
}
|
|
|
|
//simulate remote connection with a timeout
|
|
this.loadLazyTimeout = setTimeout(
|
|
() => {
|
|
let _virtualCars = [...this.virtualCars];
|
|
let { first, last } = event;
|
|
|
|
//load data of required page
|
|
const loadedCars = this.cars.slice(first, last);
|
|
|
|
//populate page of virtual cars
|
|
Array.prototype.splice.apply(_virtualCars, [...[first, last - first], ...loadedCars]);
|
|
|
|
this.virtualCars = _virtualCars;
|
|
this.lazyLoading = false;
|
|
},
|
|
Math.random() * 1000 + 250
|
|
);
|
|
}
|
|
}
|
|
};
|
|
</script>
|