chore: merge @vant/lazyload into main package

This commit is contained in:
chenjiahan
2021-11-10 17:00:02 +08:00
parent b456459249
commit 2bfbe5f86e
17 changed files with 12 additions and 122 deletions
-1
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@@ -45,7 +45,6 @@
"license": "MIT",
"dependencies": {
"@vant/icons": "^1.7.1",
"@vant/lazyload": "^1.4.0",
"@vant/popperjs": "^1.1.0",
"@vant/use": "^1.3.2"
},
+1 -1
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@@ -1,4 +1,4 @@
import { Lazyload } from '@vant/lazyload';
import { Lazyload } from './vue-lazyload';
export default Lazyload;
export { Lazyload };
+55
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@@ -0,0 +1,55 @@
import type { App } from 'vue';
declare type ListenEvent =
| 'scroll'
| 'wheel'
| 'mousewheel'
| 'resize'
| 'animationend'
| 'transitionend'
| 'touchmove';
// eslint-disable-next-line
declare type Callback = (listener: any, options: LazyloadOptions) => void;
declare type Filter = {
webp?: Callback;
progressive?: Callback;
};
declare type Adapter = {
error?: Callback;
loaded?: Callback;
loading?: Callback;
};
export declare type LazyloadOptions = {
error?: string;
filter?: Filter;
silent?: boolean;
adapter?: Adapter;
loading?: string;
attempt?: number;
preLoad?: number;
observer?: boolean;
lazyImage?: boolean;
throttleWait?: number;
listenEvents?: ListenEvent[];
dispatchEvent?: boolean;
lazyComponent?: boolean;
observerOptions?: IntersectionObserverInit;
};
export declare const Lazyload: {
install(app: App, options?: LazyloadOptions): void;
};
declare module '@vue/runtime-core' {
interface ComponentCustomProperties {
$Lazyload: {
$on: (event: string, handler: Callback) => void;
$off: (event: string, handler?: Callback) => void;
$once: (event: string, handler: Callback) => void;
};
}
}
@@ -0,0 +1,43 @@
/**
* This is a fork of [vue-lazyload](https://github.com/hilongjw/vue-lazyload) with Vue 3 support.
*/
import Lazy from './lazy';
import LazyComponent from './lazy-component';
import LazyContainer from './lazy-container';
import LazyImage from './lazy-image';
export const Lazyload = {
/*
* install function
* @param {App} app
* @param {object} options lazyload options
*/
install(app, options = {}) {
const LazyClass = Lazy();
const lazy = new LazyClass(options);
const lazyContainer = new LazyContainer({ lazy });
app.config.globalProperties.$Lazyload = lazy;
if (options.lazyComponent) {
app.component('LazyComponent', LazyComponent(lazy));
}
if (options.lazyImage) {
app.component('LazyImage', LazyImage(lazy));
}
app.directive('lazy', {
beforeMount: lazy.add.bind(lazy),
updated: lazy.update.bind(lazy),
unmounted: lazy.remove.bind(lazy),
});
app.directive('lazy-container', {
beforeMount: lazyContainer.bind.bind(lazyContainer),
updated: lazyContainer.update.bind(lazyContainer),
unmounted: lazyContainer.unbind.bind(lazyContainer),
});
},
};
@@ -0,0 +1,68 @@
import { h } from 'vue';
import { inBrowser } from '@vant/use';
export default (lazy) => ({
props: {
tag: {
type: String,
default: 'div',
},
},
emits: ['show'],
render() {
return h(
this.tag,
this.show && this.$slots.default ? this.$slots.default() : null
);
},
data() {
return {
el: null,
state: {
loaded: false,
},
rect: {},
show: false,
};
},
mounted() {
this.el = this.$el;
lazy.addLazyBox(this);
lazy.lazyLoadHandler();
},
beforeUnmount() {
lazy.removeComponent(this);
},
methods: {
getRect() {
this.rect = this.$el.getBoundingClientRect();
},
checkInView() {
this.getRect();
return (
inBrowser &&
this.rect.top < window.innerHeight * lazy.options.preLoad &&
this.rect.bottom > 0 &&
this.rect.left < window.innerWidth * lazy.options.preLoad &&
this.rect.right > 0
);
},
load() {
this.show = true;
this.state.loaded = true;
this.$emit('show', this);
},
destroy() {
return this.$destroy;
},
},
});
@@ -0,0 +1,89 @@
/* eslint-disable max-classes-per-file */
/* eslint-disable prefer-object-spread */
import { remove } from './util';
const defaultOptions = {
selector: 'img',
};
class LazyContainer {
constructor({ el, binding, vnode, lazy }) {
this.el = null;
this.vnode = vnode;
this.binding = binding;
this.options = {};
this.lazy = lazy;
this._queue = [];
this.update({ el, binding });
}
update({ el, binding }) {
this.el = el;
this.options = Object.assign({}, defaultOptions, binding.value);
const imgs = this.getImgs();
imgs.forEach((el) => {
this.lazy.add(
el,
Object.assign({}, this.binding, {
value: {
src: 'dataset' in el ? el.dataset.src : el.getAttribute('data-src'),
error:
('dataset' in el
? el.dataset.error
: el.getAttribute('data-error')) || this.options.error,
loading:
('dataset' in el
? el.dataset.loading
: el.getAttribute('data-loading')) || this.options.loading,
},
}),
this.vnode
);
});
}
getImgs() {
return Array.from(this.el.querySelectorAll(this.options.selector));
}
clear() {
const imgs = this.getImgs();
imgs.forEach((el) => this.lazy.remove(el));
this.vnode = null;
this.binding = null;
this.lazy = null;
}
}
export default class LazyContainerManager {
constructor({ lazy }) {
this.lazy = lazy;
this._queue = [];
}
bind(el, binding, vnode) {
const container = new LazyContainer({
el,
binding,
vnode,
lazy: this.lazy,
});
this._queue.push(container);
}
update(el, binding, vnode) {
const container = this._queue.find((item) => item.el === el);
if (!container) return;
container.update({ el, binding, vnode });
}
unbind(el) {
const container = this._queue.find((item) => item.el === el);
if (!container) return;
container.clear();
remove(this._queue, container);
}
}
@@ -0,0 +1,111 @@
import { inBrowser } from '@vant/use';
import { loadImageAsync, noop } from './util';
export default (lazyManager) => ({
props: {
src: [String, Object],
tag: {
type: String,
default: 'img',
},
},
render(h) {
return h(
this.tag,
{
attrs: {
src: this.renderSrc,
},
},
this.$slots.default
);
},
data() {
return {
el: null,
options: {
src: '',
error: '',
loading: '',
attempt: lazyManager.options.attempt,
},
state: {
loaded: false,
error: false,
attempt: 0,
},
rect: {},
renderSrc: '',
};
},
watch: {
src() {
this.init();
lazyManager.addLazyBox(this);
lazyManager.lazyLoadHandler();
},
},
created() {
this.init();
this.renderSrc = this.options.loading;
},
mounted() {
this.el = this.$el;
lazyManager.addLazyBox(this);
lazyManager.lazyLoadHandler();
},
beforeUnmount() {
lazyManager.removeComponent(this);
},
methods: {
init() {
const { src, loading, error } = lazyManager._valueFormatter(this.src);
this.state.loaded = false;
this.options.src = src;
this.options.error = error;
this.options.loading = loading;
this.renderSrc = this.options.loading;
},
getRect() {
this.rect = this.$el.getBoundingClientRect();
},
checkInView() {
this.getRect();
return (
inBrowser &&
this.rect.top < window.innerHeight * lazyManager.options.preLoad &&
this.rect.bottom > 0 &&
this.rect.left < window.innerWidth * lazyManager.options.preLoad &&
this.rect.right > 0
);
},
load(onFinish = noop) {
if (this.state.attempt > this.options.attempt - 1 && this.state.error) {
if (
process.env.NODE_ENV !== 'production' &&
!lazyManager.options.silent
) {
console.log(
`[@vant/lazyload] ${this.options.src} tried too more than ${this.options.attempt} times`
);
}
onFinish();
return;
}
const { src } = this.options;
loadImageAsync(
{ src },
({ src }) => {
this.renderSrc = src;
this.state.loaded = true;
},
() => {
this.state.attempt++;
this.renderSrc = this.options.error;
this.state.error = true;
}
);
},
},
});
@@ -0,0 +1,492 @@
import { nextTick } from 'vue';
import { inBrowser, getScrollParent } from '@vant/use';
import {
remove,
on,
off,
throttle,
supportWebp,
getDPR,
getBestSelectionFromSrcset,
isObject,
hasIntersectionObserver,
modeType,
ImageCache,
} from './util';
import ReactiveListener from './listener';
const DEFAULT_URL =
'data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7';
const DEFAULT_EVENTS = [
'scroll',
'wheel',
'mousewheel',
'resize',
'animationend',
'transitionend',
'touchmove',
];
const DEFAULT_OBSERVER_OPTIONS = {
rootMargin: '0px',
threshold: 0,
};
export default function () {
return class Lazy {
constructor({
preLoad,
error,
throttleWait,
preLoadTop,
dispatchEvent,
loading,
attempt,
silent = true,
scale,
listenEvents,
filter,
adapter,
observer,
observerOptions,
}) {
this.mode = modeType.event;
this.ListenerQueue = [];
this.TargetIndex = 0;
this.TargetQueue = [];
this.options = {
silent,
dispatchEvent: !!dispatchEvent,
throttleWait: throttleWait || 200,
preLoad: preLoad || 1.3,
preLoadTop: preLoadTop || 0,
error: error || DEFAULT_URL,
loading: loading || DEFAULT_URL,
attempt: attempt || 3,
scale: scale || getDPR(scale),
ListenEvents: listenEvents || DEFAULT_EVENTS,
hasbind: false,
supportWebp: supportWebp(),
filter: filter || {},
adapter: adapter || {},
observer: !!observer,
observerOptions: observerOptions || DEFAULT_OBSERVER_OPTIONS,
};
this._initEvent();
this._imageCache = new ImageCache({ max: 200 });
this.lazyLoadHandler = throttle(
this._lazyLoadHandler.bind(this),
this.options.throttleWait
);
this.setMode(this.options.observer ? modeType.observer : modeType.event);
}
/**
* update config
* @param {Object} config params
* @return
*/
config(options = {}) {
Object.assign(this.options, options);
}
/**
* output listener's load performance
* @return {Array}
*/
performance() {
return this.ListenerQueue.map((item) => item.performance());
}
/*
* add lazy component to queue
* @param {Vue} vm lazy component instance
* @return
*/
addLazyBox(vm) {
this.ListenerQueue.push(vm);
if (inBrowser) {
this._addListenerTarget(window);
this._observer && this._observer.observe(vm.el);
if (vm.$el && vm.$el.parentNode) {
this._addListenerTarget(vm.$el.parentNode);
}
}
}
/*
* add image listener to queue
* @param {DOM} el
* @param {object} binding vue directive binding
* @param {vnode} vnode vue directive vnode
* @return
*/
add(el, binding, vnode) {
if (this.ListenerQueue.some((item) => item.el === el)) {
this.update(el, binding);
return nextTick(this.lazyLoadHandler);
}
const value = this._valueFormatter(binding.value);
let { src } = value;
nextTick(() => {
src = getBestSelectionFromSrcset(el, this.options.scale) || src;
this._observer && this._observer.observe(el);
const container = Object.keys(binding.modifiers)[0];
let $parent;
if (container) {
$parent = vnode.context.$refs[container];
// if there is container passed in, try ref first, then fallback to getElementById to support the original usage
$parent = $parent
? $parent.$el || $parent
: document.getElementById(container);
}
if (!$parent) {
$parent = getScrollParent(el);
}
const newListener = new ReactiveListener({
bindType: binding.arg,
$parent,
el,
src,
loading: value.loading,
error: value.error,
cors: value.cors,
elRenderer: this._elRenderer.bind(this),
options: this.options,
imageCache: this._imageCache,
});
this.ListenerQueue.push(newListener);
if (inBrowser) {
this._addListenerTarget(window);
this._addListenerTarget($parent);
}
this.lazyLoadHandler();
nextTick(() => this.lazyLoadHandler());
});
}
/**
* update image src
* @param {DOM} el
* @param {object} vue directive binding
* @return
*/
update(el, binding, vnode) {
const value = this._valueFormatter(binding.value);
let { src } = value;
src = getBestSelectionFromSrcset(el, this.options.scale) || src;
const exist = this.ListenerQueue.find((item) => item.el === el);
if (!exist) {
this.add(el, binding, vnode);
} else {
exist.update({
src,
error: value.error,
loading: value.loading,
});
}
if (this._observer) {
this._observer.unobserve(el);
this._observer.observe(el);
}
this.lazyLoadHandler();
nextTick(() => this.lazyLoadHandler());
}
/**
* remove listener form list
* @param {DOM} el
* @return
*/
remove(el) {
if (!el) return;
this._observer && this._observer.unobserve(el);
const existItem = this.ListenerQueue.find((item) => item.el === el);
if (existItem) {
this._removeListenerTarget(existItem.$parent);
this._removeListenerTarget(window);
remove(this.ListenerQueue, existItem);
existItem.$destroy();
}
}
/*
* remove lazy components form list
* @param {Vue} vm Vue instance
* @return
*/
removeComponent(vm) {
if (!vm) return;
remove(this.ListenerQueue, vm);
this._observer && this._observer.unobserve(vm.el);
if (vm.$parent && vm.$el.parentNode) {
this._removeListenerTarget(vm.$el.parentNode);
}
this._removeListenerTarget(window);
}
setMode(mode) {
if (!hasIntersectionObserver && mode === modeType.observer) {
mode = modeType.event;
}
this.mode = mode; // event or observer
if (mode === modeType.event) {
if (this._observer) {
this.ListenerQueue.forEach((listener) => {
this._observer.unobserve(listener.el);
});
this._observer = null;
}
this.TargetQueue.forEach((target) => {
this._initListen(target.el, true);
});
} else {
this.TargetQueue.forEach((target) => {
this._initListen(target.el, false);
});
this._initIntersectionObserver();
}
}
/*
*** Private functions ***
*/
/*
* add listener target
* @param {DOM} el listener target
* @return
*/
_addListenerTarget(el) {
if (!el) return;
let target = this.TargetQueue.find((target) => target.el === el);
if (!target) {
target = {
el,
id: ++this.TargetIndex,
childrenCount: 1,
listened: true,
};
this.mode === modeType.event && this._initListen(target.el, true);
this.TargetQueue.push(target);
} else {
target.childrenCount++;
}
return this.TargetIndex;
}
/*
* remove listener target or reduce target childrenCount
* @param {DOM} el or window
* @return
*/
_removeListenerTarget(el) {
this.TargetQueue.forEach((target, index) => {
if (target.el === el) {
target.childrenCount--;
if (!target.childrenCount) {
this._initListen(target.el, false);
this.TargetQueue.splice(index, 1);
target = null;
}
}
});
}
/*
* add or remove eventlistener
* @param {DOM} el DOM or Window
* @param {boolean} start flag
* @return
*/
_initListen(el, start) {
this.options.ListenEvents.forEach((evt) =>
(start ? on : off)(el, evt, this.lazyLoadHandler)
);
}
_initEvent() {
this.Event = {
listeners: {
loading: [],
loaded: [],
error: [],
},
};
this.$on = (event, func) => {
if (!this.Event.listeners[event]) this.Event.listeners[event] = [];
this.Event.listeners[event].push(func);
};
this.$once = (event, func) => {
const on = (...args) => {
this.$off(event, on);
func.apply(this, args);
};
this.$on(event, on);
};
this.$off = (event, func) => {
if (!func) {
if (!this.Event.listeners[event]) return;
this.Event.listeners[event].length = 0;
return;
}
remove(this.Event.listeners[event], func);
};
this.$emit = (event, context, inCache) => {
if (!this.Event.listeners[event]) return;
this.Event.listeners[event].forEach((func) => func(context, inCache));
};
}
/**
* find nodes which in viewport and trigger load
* @return
*/
_lazyLoadHandler() {
const freeList = [];
this.ListenerQueue.forEach((listener) => {
if (!listener.el || !listener.el.parentNode) {
freeList.push(listener);
}
const catIn = listener.checkInView();
if (!catIn) return;
listener.load();
});
freeList.forEach((item) => {
remove(this.ListenerQueue, item);
item.$destroy();
});
}
/**
* init IntersectionObserver
* set mode to observer
* @return
*/
_initIntersectionObserver() {
if (!hasIntersectionObserver) {
return;
}
this._observer = new IntersectionObserver(
this._observerHandler.bind(this),
this.options.observerOptions
);
if (this.ListenerQueue.length) {
this.ListenerQueue.forEach((listener) => {
this._observer.observe(listener.el);
});
}
}
/**
* init IntersectionObserver
* @return
*/
_observerHandler(entries) {
entries.forEach((entry) => {
if (entry.isIntersecting) {
this.ListenerQueue.forEach((listener) => {
if (listener.el === entry.target) {
if (listener.state.loaded)
return this._observer.unobserve(listener.el);
listener.load();
}
});
}
});
}
/**
* set element attribute with image'url and state
* @param {object} lazyload listener object
* @param {string} state will be rendered
* @param {bool} inCache is rendered from cache
* @return
*/
_elRenderer(listener, state, cache) {
if (!listener.el) return;
const { el, bindType } = listener;
let src;
switch (state) {
case 'loading':
src = listener.loading;
break;
case 'error':
src = listener.error;
break;
default:
({ src } = listener);
break;
}
if (bindType) {
el.style[bindType] = 'url("' + src + '")';
} else if (el.getAttribute('src') !== src) {
el.setAttribute('src', src);
}
el.setAttribute('lazy', state);
this.$emit(state, listener, cache);
this.options.adapter[state] &&
this.options.adapter[state](listener, this.options);
if (this.options.dispatchEvent) {
const event = new CustomEvent(state, {
detail: listener,
});
el.dispatchEvent(event);
}
}
/**
* generate loading loaded error image url
* @param {string} image's src
* @return {object} image's loading, loaded, error url
*/
_valueFormatter(value) {
let src = value;
let { loading, error } = this.options;
// value is object
if (isObject(value)) {
if (
process.env.NODE_ENV !== 'production' &&
!value.src &&
!this.options.silent
) {
console.error('[@vant/lazyload] miss src with ' + value);
}
({ src } = value);
loading = value.loading || this.options.loading;
error = value.error || this.options.error;
}
return {
src,
loading,
error,
};
}
};
}
@@ -0,0 +1,251 @@
import { loadImageAsync, noop } from './util';
export default class ReactiveListener {
constructor({
el,
src,
error,
loading,
bindType,
$parent,
options,
cors,
elRenderer,
imageCache,
}) {
this.el = el;
this.src = src;
this.error = error;
this.loading = loading;
this.bindType = bindType;
this.attempt = 0;
this.cors = cors;
this.naturalHeight = 0;
this.naturalWidth = 0;
this.options = options;
this.rect = null;
this.$parent = $parent;
this.elRenderer = elRenderer;
this._imageCache = imageCache;
this.performanceData = {
loadStart: 0,
loadEnd: 0,
};
this.filter();
this.initState();
this.render('loading', false);
}
/*
* init listener state
* @return
*/
initState() {
if ('dataset' in this.el) {
this.el.dataset.src = this.src;
} else {
this.el.setAttribute('data-src', this.src);
}
this.state = {
loading: false,
error: false,
loaded: false,
rendered: false,
};
}
/*
* record performance
* @return
*/
record(event) {
this.performanceData[event] = Date.now();
}
/*
* update image listener data
* @param {String} image uri
* @param {String} loading image uri
* @param {String} error image uri
* @return
*/
update({ src, loading, error }) {
const oldSrc = this.src;
this.src = src;
this.loading = loading;
this.error = error;
this.filter();
if (oldSrc !== this.src) {
this.attempt = 0;
this.initState();
}
}
/*
* get el node rect
* @return
*/
getRect() {
this.rect = this.el.getBoundingClientRect();
}
/*
* check el is in view
* @return {Boolean} el is in view
*/
checkInView() {
this.getRect();
return (
this.rect.top < window.innerHeight * this.options.preLoad &&
this.rect.bottom > this.options.preLoadTop &&
this.rect.left < window.innerWidth * this.options.preLoad &&
this.rect.right > 0
);
}
/*
* listener filter
*/
filter() {
Object.keys(this.options.filter).forEach((key) => {
this.options.filter[key](this, this.options);
});
}
/*
* render loading first
* @params cb:Function
* @return
*/
renderLoading(cb) {
this.state.loading = true;
loadImageAsync(
{
src: this.loading,
cors: this.cors,
},
() => {
this.render('loading', false);
this.state.loading = false;
cb();
},
() => {
// handler `loading image` load failed
cb();
this.state.loading = false;
if (process.env.NODE_ENV !== 'production' && !this.options.silent)
console.warn(
`[@vant/lazyload] load failed with loading image(${this.loading})`
);
}
);
}
/*
* try load image and render it
* @return
*/
load(onFinish = noop) {
if (this.attempt > this.options.attempt - 1 && this.state.error) {
if (process.env.NODE_ENV !== 'production' && !this.options.silent) {
console.log(
`[@vant/lazyload] ${this.src} tried too more than ${this.options.attempt} times`
);
}
onFinish();
return;
}
if (this.state.rendered && this.state.loaded) return;
if (this._imageCache.has(this.src)) {
this.state.loaded = true;
this.render('loaded', true);
this.state.rendered = true;
return onFinish();
}
this.renderLoading(() => {
this.attempt++;
this.options.adapter.beforeLoad?.(this, this.options);
this.record('loadStart');
loadImageAsync(
{
src: this.src,
cors: this.cors,
},
(data) => {
this.naturalHeight = data.naturalHeight;
this.naturalWidth = data.naturalWidth;
this.state.loaded = true;
this.state.error = false;
this.record('loadEnd');
this.render('loaded', false);
this.state.rendered = true;
this._imageCache.add(this.src);
onFinish();
},
(err) => {
!this.options.silent && console.error(err);
this.state.error = true;
this.state.loaded = false;
this.render('error', false);
}
);
});
}
/*
* render image
* @param {String} state to render // ['loading', 'src', 'error']
* @param {String} is form cache
* @return
*/
render(state, cache) {
this.elRenderer(this, state, cache);
}
/*
* output performance data
* @return {Object} performance data
*/
performance() {
let state = 'loading';
let time = 0;
if (this.state.loaded) {
state = 'loaded';
time =
(this.performanceData.loadEnd - this.performanceData.loadStart) / 1000;
}
if (this.state.error) state = 'error';
return {
src: this.src,
state,
time,
};
}
/*
* $destroy
* @return
*/
$destroy() {
this.el = null;
this.src = null;
this.error = null;
this.loading = null;
this.bindType = null;
this.attempt = 0;
}
}
@@ -0,0 +1,190 @@
import { inBrowser } from '@vant/use';
export const hasIntersectionObserver =
inBrowser &&
'IntersectionObserver' in window &&
'IntersectionObserverEntry' in window &&
'intersectionRatio' in window.IntersectionObserverEntry.prototype;
export const modeType = {
event: 'event',
observer: 'observer',
};
export function remove(arr, item) {
if (!arr.length) return;
const index = arr.indexOf(item);
if (index > -1) return arr.splice(index, 1);
}
export function getBestSelectionFromSrcset(el, scale) {
if (el.tagName !== 'IMG' || !el.getAttribute('data-srcset')) return;
let options = el.getAttribute('data-srcset');
const container = el.parentNode;
const containerWidth = container.offsetWidth * scale;
let spaceIndex;
let tmpSrc;
let tmpWidth;
options = options.trim().split(',');
const result = options.map((item) => {
item = item.trim();
spaceIndex = item.lastIndexOf(' ');
if (spaceIndex === -1) {
tmpSrc = item;
tmpWidth = 999998;
} else {
tmpSrc = item.substr(0, spaceIndex);
tmpWidth = parseInt(
item.substr(spaceIndex + 1, item.length - spaceIndex - 2),
10
);
}
return [tmpWidth, tmpSrc];
});
result.sort((a, b) => {
if (a[0] < b[0]) {
return 1;
}
if (a[0] > b[0]) {
return -1;
}
if (a[0] === b[0]) {
if (b[1].indexOf('.webp', b[1].length - 5) !== -1) {
return 1;
}
if (a[1].indexOf('.webp', a[1].length - 5) !== -1) {
return -1;
}
}
return 0;
});
let bestSelectedSrc = '';
let tmpOption;
for (let i = 0; i < result.length; i++) {
tmpOption = result[i];
bestSelectedSrc = tmpOption[1];
const next = result[i + 1];
if (next && next[0] < containerWidth) {
bestSelectedSrc = tmpOption[1];
break;
} else if (!next) {
bestSelectedSrc = tmpOption[1];
break;
}
}
return bestSelectedSrc;
}
export const getDPR = (scale = 1) =>
inBrowser ? window.devicePixelRatio || scale : scale;
export function supportWebp() {
if (!inBrowser) return false;
let support = true;
try {
const elem = document.createElement('canvas');
if (elem.getContext && elem.getContext('2d')) {
support = elem.toDataURL('image/webp').indexOf('data:image/webp') === 0;
}
} catch (err) {
support = false;
}
return support;
}
export function throttle(action, delay) {
let timeout = null;
let lastRun = 0;
return function (...args) {
if (timeout) {
return;
}
const elapsed = Date.now() - lastRun;
const runCallback = () => {
lastRun = Date.now();
timeout = false;
action.apply(this, args);
};
if (elapsed >= delay) {
runCallback();
} else {
timeout = setTimeout(runCallback, delay);
}
};
}
export function on(el, type, func) {
el.addEventListener(type, func, {
capture: false,
passive: true,
});
}
export function off(el, type, func) {
el.removeEventListener(type, func, false);
}
export const loadImageAsync = (item, resolve, reject) => {
const image = new Image();
if (!item || !item.src) {
const err = new Error('image src is required');
return reject(err);
}
image.src = item.src;
if (item.cors) {
image.crossOrigin = item.cors;
}
image.onload = () =>
resolve({
naturalHeight: image.naturalHeight,
naturalWidth: image.naturalWidth,
src: image.src,
});
image.onerror = (e) => reject(e);
};
export function isObject(obj) {
return obj !== null && typeof obj === 'object';
}
export function noop() {}
export class ImageCache {
constructor({ max }) {
this.options = {
max: max || 100,
};
this._caches = [];
}
has(key) {
return this._caches.indexOf(key) > -1;
}
add(key) {
if (this.has(key)) return;
this._caches.push(key);
if (this._caches.length > this.options.max) {
this.free();
}
}
free() {
this._caches.shift();
}
}
+6 -1
View File
@@ -6,5 +6,10 @@
"emitDeclarationOnly": true
},
"include": ["es/**/*", "lib/**/*"],
"exclude": ["node_modules", "**/test/**/*", "**/demo/**/*"]
"exclude": [
"node_modules",
"**/test/**/*",
"**/demo/**/*",
"**/vue-lazyload/*"
]
}