forked from floraachy/ImageKnife
56 lines
2.1 KiB
Plaintext
56 lines
2.1 KiB
Plaintext
/*
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* Copyright (C) 2024 Huawei Device Co., Ltd.
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* Licensed under the Apache License, Version 2.0 (the 'License');
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an 'AS IS' BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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import { BasicPrefetcher } from '@kit.ArkUI';
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import DataSourcePrefetchingImageKnife, { InfoItem } from './model/DataSourcePrefetching';
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import { PageViewModel } from './model/PageViewModel';
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import { ImageKnifeComponent, ImageKnifeOption } from '@ohos/libraryimageknife';
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@Entry
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@Component
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export struct PrefetchAndPreload {
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// 创建DataSourcePrefetchingImageKnife对象，具备任务预取、取消能力的数据源
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private readonly dataSource = new DataSourcePrefetchingImageKnife(PageViewModel.getItems());
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// 创建BasicPrefetcher对象，默认的动态预取算法实现
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private readonly prefetcher = new BasicPrefetcher(this.dataSource);
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build() {
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Column() {
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List({ space: 16 }) {
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LazyForEach(this.dataSource, (item: InfoItem,index:number) => {
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ListItem() {
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Column({ space: 12 }) {
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ImageKnifeComponent({
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imageKnifeOption:{
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loadSrc: item.albumUrl,
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placeholderSrc:$r('app.media.loading')
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}
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}).width(100).height(100)
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Text(`${index}`)
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}.border({ width: 5 , color: "#000000"})
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}
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.reuseId('imageKnife')
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})
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}
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.cachedCount(5)
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.onScrollIndex((start: number, end: number) => {
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// 列表滚动触发visibleAreaChanged，实时更新预取范围，触发调用prefetch、cancel接口
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this.prefetcher.visibleAreaChanged(start, end)
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})
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.width("100%")
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.height("100%")
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.margin({ left: 10, right: 10 })
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.layoutWeight(1)
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}
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}
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} |