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appear-polyfill
Advanced tools
[](https://www.npmjs.com/package/rax-appear)
描述: 封装了组件 Appear 和 Disappear 的监听。
$ npm install appear-polyfill --save
import { createElement, render } from 'rax';
import * as DriverDOM from 'driver-dom';
import { isWeb } from 'universal-env';
import { setupAppear } from 'appear-polyfill';
if (isWeb) {
setupAppear(window);
}
const list = [];
for (let index = 1; index <= 100; index++) {
list.push(index);
}
render((
<div>
{list.map((item) => {
return (
<div
style={{
height: 100,
backgroundColor: '#ccc',
marginBottom: 20,
display: 'flex',
alignItems: 'center',
justifyContent: 'center',
}}
onAppear={(event) => {
console.log('appear: ', item, event.detail.direction);
}}
onDisappear={() => {
console.log('disappear: ', item, event.detail.direction);
}}
>
第 {item} 个
</div>
);
})}
</div>
), document.body, { driver: DriverDOM });
preAppear
string支持预加载浏览器视口底部更多偏移的内容,单位 px。为需要预加载的元素设置 preappear 事件。
import { createElement, render } from 'rax';
import DriverUniversal from 'driver-universal';
import Image from 'rax-image';
import { setupAppear } from 'appear-polyfill';
if (isWeb) {
setupAppear(window, {
preAppear: '0px 0px 100px 0px'
});
}
const App = () => {
const rendderImage = () => (
<Image
onPreappear={(e) => { console.log(e); }}
source={{
uri: 'https://gw.alicdn.com/tfs/TB1bBD0zCzqK1RjSZFpXXakSXXa-68-67.png',
}}
style={{
height: 300,
width: '100%',
}}
/>
);
return (
<div>
{
new Array(10).map(rendderImage)
}
</div>
);
};
render(<App />, document.body, { driver: DriverUniversal });
FAQs
[](https://www.npmjs.com/package/rax-appear)
We found that appear-polyfill demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 3 open source maintainers collaborating on the project.
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