目录
- 效果
- 实现
- card-slider.tsx
- card-item.tsx
- App.tsx
效果
实现
通过zIndex控制层级,opacity控制透明度,transform 控制卡片缩放程度,marginLeft控制位置,剩下的就是计算的事了
card-slider.tsx
import React from 'react'
export type CardProps = {
opacity: number
scale: number
loop?: boolean
width: number
disablePrev?: boolean
disableNext?: boolean
boxWidth: number
index?: number
list: any[]
renderItem(data: any): React.ReactNode
onChange?: (index: number, data: any) => void
style?: React.CSSProperties
}
type CardState = {
activeIndex: number
moving: boolean
}
export default class CardSlider extends React.Component<CardProps, CardState> {
static defaultProps: Partial<CardProps> = {
opacity: 0.9,
scale: 0.9,
loop: false,
disablePrev: false,
disableNext: false
}
constructor(props: CardProps) {
super(props)
this.state = {
activeIndex: props.index || 0,
moving: false
}
}
componentWillReceiveProps(nextProps: any) {
if (this.props.index !== nextProps.index) {
this.setState({
activeIndex: nextProps.index
})
}
}
// 卡片总数量get totalCount() {return this.props.list.length
}
// 间隔宽度get gridWidth() {const isEven = this.totalCount % 2 === 0const { width, boxWidth } = this.propsreturn (boxWidth - width) / (isEven ? this.totalCount : this.totalCount - 1)
}
// 禁用prevget disablePrev() {const { loop, disablePrev } = this.propsconst { activeIndex } = this.stateif (disablePrev) return truereturn !loop && activeIndex === 0
}
// 禁用prevget disableNext() {const { loop, disableNext } = this.propsconst { activeIndex } = this.stateif (disableNext) return truereturn !loop && activeIndex === this.totalCount - 1
}
/**
* offset: 是左或者右的第几个
* direction: 1:右侧:-1:左侧
*/
getDirection(index: number) {
const { activeIndex } = this.state
let direction = 1if (
index - activeIndex > this.totalCount / 2 ||
(index - activeIndex < 0 && index - activeIndex > -this.totalCount / 2)
) {
direction = -1
}
let offset = Math.abs(index - activeIndex)
if (offset > this.totalCount / 2) {
offset = activeIndex + this.totalCount - index
}
if (index - activeIndex < -this.totalCount / 2) {
offset = this.totalCount + index - activeIndex
}
return {
direction,
offset
}
}
render() {
const { list, renderItem, opacity, scale, width, boxWidth, style = {} } = this.props
return (
<div style={{ ...styles.wrapper, ...style }}>
<div style={{ ...styles.content, width: boxWidth }}>
{list.map((data, index) => {
const { direction, offset } = this.getDirection(index)
const realScale = Math.pow(scale, offset)
return renderItem({
key: index,
...data,
style: {
position: 'absolute',
left: '50%',
marginLeft: this.gridWidth * direction * offset + direction * ((width / 2) * (1 - realScale)),
zIndex: this.totalCount - offset,
opacity: Math.pow(opacity, offset),
transform: `translateX(-50%) translateZ(0) scale(${realScale})`,
transition: 'all 300ms'
}
})
})}
</div>
{!this.disablePrev && (
<a href="javascript:;" rel="external nofollow" rel="external nofollow" style={{ ...styles.btn, left: 35 }} onClick={this.handlePrev}>
{'<'}
</a>
)}
{!this.disableNext && (
<a href="javascript:;" rel="external nofollow" rel="external nofollow" style={{ ...styles.btn, right: 35 }} onClick={this.handleNext}>
{'>'}
</a>
)}
</div>
)
}
handlePrev = () => {
let { activeIndex } = this.state
if (this.disablePrev) return
activeIndex = --activeIndex < 0 ? this.totalCount - 1 : activeIndex
this.setState({ activeIndex })
this.handleChange(activeIndex)
}
handleNext = () => {
let { activeIndex } = this.state
if (this.disableNext) return
activeIndex = ++activeIndex >= this.totalCount ? 0 : activeIndex
this.setState({ activeIndex })
this.handleChange(activeIndex)
}
handleChange = (index: number) => {
const { list, onChange } = this.props
onChange && onChange(index, list[index])
}
}
const styles: { [name: string]: React.CSSProperties } = {
wrapper: {
position: 'relative',
display: 'flex',
justifyContent: 'center',
width: '100%'
},
content: {
height: 210,
position: 'relative'
},
btn: {
position: 'absolute',
top: '50%',
transform: 'translateY(-50%)',
width: 36,
height: 36,
zIndex: 99,
display: 'flex',
justifyContent: 'center',
alignItems: 'center',
fontSize: 24
}
}
card-item.tsx
import React from 'react'
const CardItem = ({ style, url }) => {
return (
<divstyle={{width: 375,
height: 208,
background: '#000',
color: '#fff',
borderRadius: 5,
textAlign: 'center',
...style
}}
><img src={url} width="100%" height="100%" /></div>
)
}
export default CardItem
App.tsx
import CardSlider from './card-slider'
import CardItem from './card-item'
import './App.scss'
const list = [
{
name: '1',
url: 'https://m15.360buyimg.com/mobilecms/jfs/t1/218369/27/14203/132191/6226a702E5a0b9236/a11294e884bc7635.jpg!cr_1053x420_4_0!q70.jpg'
},
{
name: '2',
url: 'https://m15.360buyimg.com/mobilecms/jfs/t1/158791/25/27003/106834/620c4bc2Efb15fc57/7c89841a597ce41b.jpg!cr_1053x420_4_0!q70.jpg'
},
{
name: '3',
url: 'https://m15.360buyimg.com/mobilecms/jfs/t1/117358/2/22877/138901/6228342eE68ae2c88/f8a9adb2642c1313.jpg!cr_1053x420_4_0!q70.jpg'
},
{
name: '4',
url: 'https://m15.360buyimg.com/mobilecms/jfs/t1/121592/2/24818/138081/622ccc8fEdf840f95/cd229433d699c70c.jpg!cr_1053x420_4_0!q70.jpg'
},
{
name: '5',
url: 'https://imgcps.jd.com/ling-cubic/danpin/lab/amZzL3QxLzE2Mjc4Mi8zNi85MTM4LzQ0NjQ1MS82MDQwN2Q4MUVkMDlmMWM5OC9jZWVmOWU0OWVkNzlkNjZkLnBuZw/6Zi_6L-q6L6-5pav6LeR5q2l6Z6L/5qmh6IO25aSW5bqV/60586f6fa1b18f3314204f2d/cr_1125x449_0_166/s/q70.jpg'
},
{
name: '6',
url: 'https://imgcps.jd.com/img-cubic/creative_server_cid/v2/2000755/10041170380456/FocusActivity/CkNqZnMvdDEvMjExMDQ2LzIyLzExMTc3Lzc0NTA0LzYxYTU4MzAwRWU1YjQ0OTcxL2Q5YjE5NzlmOGJkMjAzNzIuanBnEgs4NDIteGNfMF81MjABOPOOekIWChLkuprnkZ_lo6vot5HmraXpnosQAEIQCgzpkpzmg6DnmbvlnLoQAUIQCgznq4vljbPmiqLotK0QAkIKCgbkvJjpgIkQBw/cr_1053x420_4_0/s/q70.jpg'
},
{
name: '7',
url: 'https://m15.360buyimg.com/mobilecms/jfs/t1/117358/2/22877/138901/6228342eE68ae2c88/f8a9adb2642c1313.jpg!cr_1053x420_4_0!q70.jpg'
}
]
export default function App() {
return (
<div style={{ paddingTop: '20%'}}><CardSliderlist={list}renderItem={CardItem}width={375}boxWidth={500}opacity={0.75}scale={0.9}disableNext={false}disablePrev={false}onChange={(index: number, data: any) => {
console.log(index, data)
}}
/>
</div>
)
}