287 lines
9.4 KiB
Vue
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<template>
<uv-transition
v-if="show"
:show="show"
mode="fade"
:duration="fade ? duration : 0"
:cell-child="cellChild"
:custom-style="wrapStyle"
>
<view
class="uv-image"
:class="[`uv-image--${elIndex}`]"
@tap="onClick"
:style="[wrapStyle, backgroundStyle]"
>
<image
v-if="!isError && observeShow"
:src="src"
:mode="mode"
@error="onErrorHandler"
@load="onLoadHandler"
:show-menuv-by-longpress="showMenuByLongpress"
:lazy-load="lazyLoad"
class="uv-image__image"
:style="[imageStyle]"
></image>
<view
v-if="showLoading && loading"
class="uv-image__loading"
:style="{
borderRadius: shape == 'circle' ? '50%' : $uv.addUnit(radius),
backgroundColor: bgColor,
width: $uv.addUnit(width),
height: $uv.addUnit(height)
}"
>
<slot name="loading">
<uv-icon
:name="loadingIcon"
:width="width"
:height="height"
></uv-icon>
</slot>
</view>
<view
v-if="showError && isError && !loading"
class="uv-image__error"
:style="{
borderRadius: shape == 'circle' ? '50%' : $uv.addUnit(radius),
width: $uv.addUnit(width),
height: $uv.addUnit(height)
}"
>
<slot name="error">
<uv-icon
:name="errorIcon"
:width="width"
:height="height"
></uv-icon>
</slot>
</view>
</view>
</uv-transition>
</template>
<script>
import mpMixin from '@/uni_modules/uv-ui-tools/libs/mixin/mpMixin.js'
import mixin from '@/uni_modules/uv-ui-tools/libs/mixin/mixin.js'
import props from './props.js';
/**
* Image 图片
* @description 此组件为uni-app的image组件的加强版在继承了原有功能外还支持淡入动画、加载中、加载失败提示、圆角值和形状等。
* @tutorial https://www.uvui.cn/components/image.html
* @property {String} src 图片地址
* @property {String} mode 裁剪模式,见官网说明 (默认 'aspectFill'
* @property {String | Number} width 宽度单位任意如果为数值则为px单位 (默认 '300'
* @property {String | Number} height 高度单位任意如果为数值则为px单位 (默认 '225'
* @property {String} shape 图片形状circle-圆形square-方形 (默认 'square'
* @property {String | Number} radius 圆角值单位任意如果为数值则为px单位 (默认 0
* @property {Boolean} lazyLoad 是否懒加载仅微信小程序、App、百度小程序、字节跳动小程序有效 (默认 true
* @property {Boolean} showMenuByLongpress 是否开启长按图片显示识别小程序码菜单,仅微信小程序有效 (默认 true
* @property {String} loadingIcon 加载中的图标,或者小图片 (默认 'photo'
* @property {String} errorIcon 加载失败的图标,或者小图片 (默认 'error-circle'
* @property {Boolean} showLoading 是否显示加载中的图标或者自定义的slot (默认 true
* @property {Boolean} showError 是否显示加载错误的图标或者自定义的slot (默认 true
* @property {Boolean} fade 是否需要淡入效果 (默认 true
* @property {Boolean} webp 只支持网络资源,只对微信小程序有效 (默认 false
* @property {String | Number} duration 搭配fade参数的过渡时间单位ms (默认 500
* @property {String} bgColor 背景颜色,用于深色页面加载图片时,为了和背景色融合 (默认 '#f3f4f6' )
* @property {Object} customStyle 定义需要用到的外部样式
* @event {Function} click 点击图片时触发
* @event {Function} error 图片加载失败时触发
* @event {Function} load 图片加载成功时触发
* @example <uv-image width="100%" height="300px" :src="src"></uv-image>
*/
export default {
name: 'uv-image',
emits: ['click','load','error'],
mixins: [mpMixin, mixin, props],
data() {
return {
// 图片是否加载错误,如果是,则显示错误占位图
isError: false,
// 初始化组件时,默认为加载中状态
loading: true,
// 图片加载完成时去掉背景颜色因为如果是png图片就会显示灰色的背景
backgroundStyle: {},
// 用于fade模式的控制组件显示与否
show: false,
// 是否开启图片出现在可视范围进行加载(另一种懒加载)
observeShow: !this.observeLazyLoad,
elIndex: '',
// 因为props的值无法修改故需要一个中间值
imgWidth: this.width,
// 因为props的值无法修改故需要一个中间值
imgHeight: this.height,
thresholdValue: 50
};
},
watch: {
src: {
immediate: true,
handler(n) {
if (!n) {
// 如果传入null或者''或者false或者undefined标记为错误状态
this.isError = true
} else {
this.isError = false;
this.loading = true;
}
}
},
width(newVal){
// 这样做的目的是避免在更新时候,某些平台动画会恢复关闭状态
this.show = false;
this.$uv.sleep(2).then(res=>{
this.show = true;
});
this.imgWidth = newVal;
},
height(newVal){
// 这样做的目的是避免在更新时候,某些平台动画会恢复关闭状态
this.show = false;
this.$uv.sleep(2).then(res=>{
this.show = true;
});
this.imgHeight = newVal;
}
},
computed: {
wrapStyle() {
let style = {};
// 通过调用addUnit()方法如果有单位如百分比px单位等直接返回如果是纯粹的数值则加上rpx单位
if(this.mode !== 'heightFix') {
style.width = this.$uv.addUnit(this.imgWidth);
}
if(this.mode !== 'widthFix') {
style.height = this.$uv.addUnit(this.imgHeight);
}
// 如果是显示圆形,设置一个很多的半径值即可
style.borderRadius = this.shape == 'circle' ? '10000px' : this.$uv.addUnit(this.radius)
// 如果设置圆角必须要有hidden否则可能圆角无效
style.overflow = this.radius > 0 ? 'hidden' : 'visible'
return this.$uv.deepMerge(style, this.$uv.addStyle(this.customStyle));
},
imageStyle() {
let style = {};
style.borderRadius = this.shape == 'circle' ? '10000px' : this.$uv.addUnit(this.radius);
// #ifdef APP-NVUE
style.width = this.$uv.addUnit(this.imgWidth);
style.height = this.$uv.addUnit(this.imgHeight);
// #endif
return style;
}
},
created() {
this.elIndex = this.$uv.guid();
this.observer = {}
this.observerName = 'lazyLoadContentObserver'
},
mounted() {
this.show = true;
this.$nextTick(()=>{
if(this.observeLazyLoad) this.observerFn();
})
},
methods: {
// 点击图片
onClick() {
this.$emit('click')
},
// 图片加载失败
onErrorHandler(err) {
this.loading = false
this.isError = true
this.$emit('error', err)
},
// 图片加载完成标记loading结束
onLoadHandler(event) {
if(this.mode == 'widthFix') this.imgHeight = 'auto'
if(this.mode == 'heightFix') this.imgWidth = 'auto'
this.loading = false
this.isError = false
this.$emit('load', event)
this.removeBgColor()
},
// 移除图片的背景色
removeBgColor() {
// 淡入动画过渡完成后将背景设置为透明色否则png图片会看到灰色的背景
this.backgroundStyle = {
backgroundColor: 'transparent'
};
},
// 观察图片是否在可见视口
observerFn(){
// 在需要用到懒加载的页面在触发底部的时候触发tOnLazyLoadReachBottom事件保证所有图片进行加载
this.$nextTick(() => {
uni.$once('onLazyLoadReachBottom', () => {
if (!this.observeShow) this.observeShow = true
})
})
setTimeout(() => {
// #ifndef APP-NVUE
this.disconnectObserver(this.observerName)
const contentObserver = uni.createIntersectionObserver(this)
contentObserver.relativeToViewport({
bottom: this.thresholdValue
}).observe(`.uv-image--${this.elIndex}`, (res) => {
if (res.intersectionRatio > 0) {
// 懒加载状态改变
this.observeShow = true
// 如果图片已经加载,去掉监听,减少性能消耗
this.disconnectObserver(this.observerName)
}
})
this[this.observerName] = contentObserver
// #endif
// #ifdef APP-NVUE
this.observeShow = true;
// #endif
}, 50)
},
disconnectObserver(observerName) {
const observer = this[observerName]
observer && observer.disconnect()
}
}
};
</script>
<style lang="scss" scoped>
@import '@/uni_modules/uv-ui-tools/libs/css/components.scss';
@import '@/uni_modules/uv-ui-tools/libs/css/color.scss';
$uv-image-error-top:0px !default;
$uv-image-error-left:0px !default;
$uv-image-error-width:100% !default;
$uv-image-error-hight:100% !default;
$uv-image-error-background-color:$uv-bg-color !default;
$uv-image-error-color:$uv-tips-color !default;
$uv-image-error-font-size: 46rpx !default;
.uv-image {
position: relative;
transition: opacity 0.5s ease-in-out;
&__image {
width: 100%;
height: 100%;
}
&__loading,
&__error {
position: absolute;
top: $uv-image-error-top;
left: $uv-image-error-left;
width: $uv-image-error-width;
height: $uv-image-error-hight;
@include flex;
align-items: center;
justify-content: center;
background-color: $uv-image-error-background-color;
color: $uv-image-error-color;
font-size: $uv-image-error-font-size;
}
}
</style>