ckgl/node_modules/vant/lib/lazyload/vue-lazyload/lazy.js
2024-12-21 13:52:42 +08:00

456 lines
14 KiB
JavaScript

var __create = Object.create;
var __defProp = Object.defineProperty;
var __getOwnPropDesc = Object.getOwnPropertyDescriptor;
var __getOwnPropNames = Object.getOwnPropertyNames;
var __getProtoOf = Object.getPrototypeOf;
var __hasOwnProp = Object.prototype.hasOwnProperty;
var __export = (target, all) => {
for (var name in all)
__defProp(target, name, { get: all[name], enumerable: true });
};
var __copyProps = (to, from, except, desc) => {
if (from && typeof from === "object" || typeof from === "function") {
for (let key of __getOwnPropNames(from))
if (!__hasOwnProp.call(to, key) && key !== except)
__defProp(to, key, { get: () => from[key], enumerable: !(desc = __getOwnPropDesc(from, key)) || desc.enumerable });
}
return to;
};
var __toESM = (mod, isNodeMode, target) => (target = mod != null ? __create(__getProtoOf(mod)) : {}, __copyProps(
// If the importer is in node compatibility mode or this is not an ESM
// file that has been converted to a CommonJS file using a Babel-
// compatible transform (i.e. "__esModule" has not been set), then set
// "default" to the CommonJS "module.exports" for node compatibility.
isNodeMode || !mod || !mod.__esModule ? __defProp(target, "default", { value: mod, enumerable: true }) : target,
mod
));
var __toCommonJS = (mod) => __copyProps(__defProp({}, "__esModule", { value: true }), mod);
var stdin_exports = {};
__export(stdin_exports, {
default: () => stdin_default
});
module.exports = __toCommonJS(stdin_exports);
var import_vue = require("vue");
var import_use = require("@vant/use");
var import_util = require("./util");
var import_utils = require("../../utils");
var import_listener = __toESM(require("./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
};
function stdin_default() {
return class Lazy {
constructor({
preLoad,
error,
throttleWait,
preLoadTop,
dispatchEvent,
loading,
attempt,
silent = true,
scale,
listenEvents,
filter,
adapter,
observer,
observerOptions
}) {
this.mode = import_util.modeType.event;
this.listeners = [];
this.targetIndex = 0;
this.targets = [];
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 || (0, import_util.getDPR)(scale),
ListenEvents: listenEvents || DEFAULT_EVENTS,
supportWebp: (0, import_util.supportWebp)(),
filter: filter || {},
adapter: adapter || {},
observer: !!observer,
observerOptions: observerOptions || DEFAULT_OBSERVER_OPTIONS
};
this.initEvent();
this.imageCache = new import_util.ImageCache({ max: 200 });
this.lazyLoadHandler = (0, import_util.throttle)(
this.lazyLoadHandler.bind(this),
this.options.throttleWait
);
this.setMode(this.options.observer ? import_util.modeType.observer : import_util.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.listeners.map((item) => item.performance());
}
/*
* add lazy component to queue
* @param {Vue} vm lazy component instance
* @return
*/
addLazyBox(vm) {
this.listeners.push(vm);
if (import_use.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.listeners.some((item) => item.el === el)) {
this.update(el, binding);
return (0, import_vue.nextTick)(this.lazyLoadHandler);
}
const value = this.valueFormatter(binding.value);
let { src } = value;
(0, import_vue.nextTick)(() => {
src = (0, import_util.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];
$parent = $parent ? $parent.$el || $parent : document.getElementById(container);
}
if (!$parent) {
$parent = (0, import_use.getScrollParent)(el);
}
const newListener = new import_listener.default({
bindType: binding.arg,
$parent,
el,
src,
loading: value.loading,
error: value.error,
cors: value.cors,
elRenderer: this.elRenderer.bind(this),
options: this.options,
imageCache: this.imageCache
});
this.listeners.push(newListener);
if (import_use.inBrowser) {
this.addListenerTarget(window);
this.addListenerTarget($parent);
}
this.lazyLoadHandler();
(0, import_vue.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 = (0, import_util.getBestSelectionFromSrcset)(el, this.options.scale) || src;
const exist = this.listeners.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();
(0, import_vue.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.listeners.find((item) => item.el === el);
if (existItem) {
this.removeListenerTarget(existItem.$parent);
this.removeListenerTarget(window);
(0, import_util.remove)(this.listeners, existItem);
existItem.$destroy();
}
}
/*
* remove lazy components form list
* @param {Vue} vm Vue instance
* @return
*/
removeComponent(vm) {
if (!vm) return;
(0, import_util.remove)(this.listeners, vm);
this.observer && this.observer.unobserve(vm.el);
if (vm.$parent && vm.$el.parentNode) {
this.removeListenerTarget(vm.$el.parentNode);
}
this.removeListenerTarget(window);
}
setMode(mode) {
if (!import_util.hasIntersectionObserver && mode === import_util.modeType.observer) {
mode = import_util.modeType.event;
}
this.mode = mode;
if (mode === import_util.modeType.event) {
if (this.observer) {
this.listeners.forEach((listener) => {
this.observer.unobserve(listener.el);
});
this.observer = null;
}
this.targets.forEach((target) => {
this.initListen(target.el, true);
});
} else {
this.targets.forEach((target) => {
this.initListen(target.el, false);
});
this.initIntersectionObserver();
}
}
/*
*** Private functions ***
*/
/*
* add listener target
* @param {DOM} el listener target
* @return
*/
addListenerTarget(el) {
if (!el) return;
let target = this.targets.find((target2) => target2.el === el);
if (!target) {
target = {
el,
id: ++this.targetIndex,
childrenCount: 1,
listened: true
};
this.mode === import_util.modeType.event && this.initListen(target.el, true);
this.targets.push(target);
} else {
target.childrenCount++;
}
return this.targetIndex;
}
/*
* remove listener target or reduce target childrenCount
* @param {DOM} el or window
* @return
*/
removeListenerTarget(el) {
this.targets.forEach((target, index) => {
if (target.el === el) {
target.childrenCount--;
if (!target.childrenCount) {
this.initListen(target.el, false);
this.targets.splice(index, 1);
target = null;
}
}
});
}
/*
* add or remove eventlistener
* @param {DOM} el DOM or Window
* @param {boolean} start flag
* @return
*/
initListen(el, start) {
this.options.ListenEvents.forEach(
(evt) => (start ? import_util.on : import_util.off)(el, evt, this.lazyLoadHandler)
);
}
initEvent() {
this.Event = {
listeners: {
loading: [],
loaded: [],
error: []
}
};
this.$on = (event, func) => {
if (!this.Event.listeners[event]) this.Event.listeners[event] = [];
this.Event.listeners[event].push(func);
};
this.$once = (event, func) => {
const on2 = (...args) => {
this.$off(event, on2);
func.apply(this, args);
};
this.$on(event, on2);
};
this.$off = (event, func) => {
if (!func) {
if (!this.Event.listeners[event]) return;
this.Event.listeners[event].length = 0;
return;
}
(0, import_util.remove)(this.Event.listeners[event], func);
};
this.$emit = (event, context, inCache) => {
if (!this.Event.listeners[event]) return;
this.Event.listeners[event].forEach((func) => func(context, inCache));
};
}
/**
* find nodes which in viewport and trigger load
* @return
*/
lazyLoadHandler() {
const freeList = [];
this.listeners.forEach((listener) => {
if (!listener.el || !listener.el.parentNode) {
freeList.push(listener);
}
const catIn = listener.checkInView();
if (!catIn) return;
listener.load();
});
freeList.forEach((item) => {
(0, import_util.remove)(this.listeners, item);
item.$destroy();
});
}
/**
* init IntersectionObserver
* set mode to observer
* @return
*/
initIntersectionObserver() {
if (!import_util.hasIntersectionObserver) {
return;
}
this.observer = new IntersectionObserver(
this.observerHandler.bind(this),
this.options.observerOptions
);
if (this.listeners.length) {
this.listeners.forEach((listener) => {
this.observer.observe(listener.el);
});
}
}
/**
* init IntersectionObserver
* @return
*/
observerHandler(entries) {
entries.forEach((entry) => {
if (entry.isIntersecting) {
this.listeners.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;
if ((0, import_utils.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
};
}
};
}