60 lines
1.5 KiB
Vue
Executable File
60 lines
1.5 KiB
Vue
Executable File
<template>
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<div ref="container">
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<slot v-if="loaded"></slot>
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</div>
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</template>
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<script>
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export default {
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name: 'DeferredContent',
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emits: ['load'],
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data() {
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return {
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loaded: false
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};
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},
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mounted() {
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if (!this.loaded) {
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if (this.shouldLoad()) this.load();
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else this.bindScrollListener();
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}
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},
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beforeUnmount() {
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this.unbindScrollListener();
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},
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methods: {
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bindScrollListener() {
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this.documentScrollListener = () => {
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if (this.shouldLoad()) {
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this.load();
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this.unbindScrollListener();
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}
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};
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window.addEventListener('scroll', this.documentScrollListener);
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},
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unbindScrollListener() {
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if (this.documentScrollListener) {
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window.removeEventListener('scroll', this.documentScrollListener);
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this.documentScrollListener = null;
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}
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},
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shouldLoad() {
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if (this.loaded) {
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return false;
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} else {
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const rect = this.$refs.container.getBoundingClientRect();
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const docElement = document.documentElement;
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const winHeight = docElement.clientHeight;
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return winHeight >= rect.top;
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}
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},
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load(event) {
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this.loaded = true;
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this.$emit('load', event);
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}
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}
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};
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</script>
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