806 lines
33 KiB
Vue
806 lines
33 KiB
Vue
<template>
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<template v-if="!disabled">
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<div :ref="elementRef" :class="containerClass" :tabindex="tabindex" :style="style" @scroll="onScroll">
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<slot
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name="content"
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:styleClass="contentClass"
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:items="loadedItems"
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:getItemOptions="getOptions"
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:loading="d_loading"
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:getLoaderOptions="getLoaderOptions"
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:itemSize="itemSize"
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:rows="loadedRows"
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:columns="loadedColumns"
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:contentRef="contentRef"
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:spacerStyle="spacerStyle"
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:contentStyle="contentStyle"
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:vertical="isVertical()"
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:horizontal="isHorizontal()"
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:both="isBoth()"
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>
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<div :ref="contentRef" :class="contentClass" :style="contentStyle">
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<template v-for="(item, index) of loadedItems" :key="index">
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<slot name="item" :item="item" :options="getOptions(index)"></slot>
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</template>
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</div>
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</slot>
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<div v-if="showSpacer" class="p-virtualscroller-spacer" :style="spacerStyle"></div>
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<div v-if="!loaderDisabled && showLoader && d_loading" :class="loaderClass">
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<template v-if="$slots && $slots.loader">
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<template v-for="(_, index) of loaderArr" :key="index">
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<slot name="loader" :options="getLoaderOptions(index, isBoth() && { numCols: d_numItemsInViewport.cols })"></slot>
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</template>
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</template>
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<i v-else class="p-virtualscroller-loading-icon pi pi-spinner pi-spin"></i>
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</div>
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</div>
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</template>
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<template v-else>
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<slot></slot>
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<slot name="content" :items="items" :rows="items" :columns="loadedColumns"></slot>
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</template>
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</template>
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<script>
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import { DomHandler } from 'primevue/utils';
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export default {
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name: 'VirtualScroller',
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emits: ['update:numToleratedItems', 'scroll', 'scroll-index-change', 'lazy-load'],
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props: {
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id: {
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type: String,
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default: null
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},
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style: null,
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class: null,
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items: {
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type: Array,
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default: null
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},
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itemSize: {
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type: [Number, Array],
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default: 0
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},
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scrollHeight: null,
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scrollWidth: null,
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orientation: {
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type: String,
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default: 'vertical'
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},
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numToleratedItems: {
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type: Number,
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default: null
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},
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delay: {
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type: Number,
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default: 0
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},
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resizeDelay: {
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type: Number,
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default: 10
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},
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lazy: {
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type: Boolean,
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default: false
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},
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disabled: {
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type: Boolean,
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default: false
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},
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loaderDisabled: {
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type: Boolean,
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default: false
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},
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columns: {
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type: Array,
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default: null
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},
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loading: {
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type: Boolean,
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default: false
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},
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showSpacer: {
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type: Boolean,
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default: true
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},
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showLoader: {
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type: Boolean,
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default: false
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},
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tabindex: {
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type: Number,
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default: 0
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},
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inline: {
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type: Boolean,
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default: false
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},
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step: {
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type: Number,
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default: 0
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},
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appendOnly: {
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type: Boolean,
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default: false
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},
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autoSize: {
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type: Boolean,
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default: false
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}
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},
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data() {
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return {
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first: this.isBoth() ? { rows: 0, cols: 0 } : 0,
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last: this.isBoth() ? { rows: 0, cols: 0 } : 0,
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page: this.isBoth() ? { rows: 0, cols: 0 } : 0,
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numItemsInViewport: this.isBoth() ? { rows: 0, cols: 0 } : 0,
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lastScrollPos: this.isBoth() ? { top: 0, left: 0 } : 0,
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d_numToleratedItems: this.numToleratedItems,
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d_loading: this.loading,
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loaderArr: [],
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spacerStyle: {},
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contentStyle: {}
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};
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},
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element: null,
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content: null,
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lastScrollPos: null,
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scrollTimeout: null,
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resizeTimeout: null,
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defaultWidth: 0,
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defaultHeight: 0,
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defaultContentWidth: 0,
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defaultContentHeight: 0,
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isRangeChanged: false,
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lazyLoadState: {},
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resizeListener: null,
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initialized: false,
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watch: {
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numToleratedItems(newValue) {
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this.d_numToleratedItems = newValue;
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},
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loading(newValue) {
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this.d_loading = newValue;
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},
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items(newValue, oldValue) {
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if (!oldValue || oldValue.length !== (newValue || []).length) {
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this.init();
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this.calculateAutoSize();
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}
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},
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itemSize() {
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this.init();
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this.calculateAutoSize();
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},
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orientation() {
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this.lastScrollPos = this.isBoth() ? { top: 0, left: 0 } : 0;
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},
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scrollHeight() {
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this.init();
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this.calculateAutoSize();
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},
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scrollWidth() {
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this.init();
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this.calculateAutoSize();
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}
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},
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mounted() {
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this.viewInit();
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this.lastScrollPos = this.isBoth() ? { top: 0, left: 0 } : 0;
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this.lazyLoadState = this.lazyLoadState || {};
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},
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updated() {
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!this.initialized && this.viewInit();
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},
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unmounted() {
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this.unbindResizeListener();
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this.initialized = false;
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},
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methods: {
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viewInit() {
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if (DomHandler.isVisible(this.element)) {
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this.setContentEl(this.content);
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this.init();
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this.bindResizeListener();
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this.defaultWidth = DomHandler.getWidth(this.element);
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this.defaultHeight = DomHandler.getHeight(this.element);
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this.defaultContentWidth = DomHandler.getWidth(this.content);
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this.defaultContentHeight = DomHandler.getHeight(this.content);
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this.initialized = true;
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}
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},
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init() {
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if (!this.disabled) {
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this.setSize();
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this.calculateOptions();
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this.setSpacerSize();
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}
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},
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isVertical() {
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return this.orientation === 'vertical';
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},
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isHorizontal() {
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return this.orientation === 'horizontal';
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},
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isBoth() {
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return this.orientation === 'both';
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},
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scrollTo(options) {
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this.lastScrollPos = this.both ? { top: 0, left: 0 } : 0;
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this.element && this.element.scrollTo(options);
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},
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scrollToIndex(index, behavior = 'auto') {
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const both = this.isBoth();
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const horizontal = this.isHorizontal();
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const first = this.first;
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const { numToleratedItems } = this.calculateNumItems();
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const contentPos = this.getContentPosition();
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const itemSize = this.itemSize;
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const calculateFirst = (_index = 0, _numT) => (_index <= _numT ? 0 : _index);
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const calculateCoord = (_first, _size, _cpos) => _first * _size + _cpos;
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const scrollTo = (left = 0, top = 0) => this.scrollTo({ left, top, behavior });
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let newFirst = both ? { rows: 0, cols: 0 } : 0;
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let isRangeChanged = false;
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if (both) {
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newFirst = { rows: calculateFirst(index[0], numToleratedItems[0]), cols: calculateFirst(index[1], numToleratedItems[1]) };
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scrollTo(calculateCoord(newFirst.cols, itemSize[1], contentPos.left), calculateCoord(newFirst.rows, itemSize[0], contentPos.top));
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isRangeChanged = newFirst.rows !== first.rows || newFirst.cols !== first.cols;
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} else {
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newFirst = calculateFirst(index, numToleratedItems);
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horizontal ? scrollTo(calculateCoord(newFirst, itemSize, contentPos.left), 0) : scrollTo(0, calculateCoord(newFirst, itemSize, contentPos.top));
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isRangeChanged = newFirst !== first;
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}
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this.isRangeChanged = isRangeChanged;
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this.first = newFirst;
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},
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scrollInView(index, to, behavior = 'auto') {
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if (to) {
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const both = this.isBoth();
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const horizontal = this.isHorizontal();
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const { first, viewport } = this.getRenderedRange();
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const scrollTo = (left = 0, top = 0) => this.scrollTo({ left, top, behavior });
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const isToStart = to === 'to-start';
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const isToEnd = to === 'to-end';
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if (isToStart) {
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if (both) {
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if (viewport.first.rows - first.rows > index[0]) {
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scrollTo(viewport.first.cols * this.itemSize[1], (viewport.first.rows - 1) * this.itemSize[0]);
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} else if (viewport.first.cols - first.cols > index[1]) {
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scrollTo((viewport.first.cols - 1) * this.itemSize[1], viewport.first.rows * this.itemSize[0]);
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}
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} else {
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if (viewport.first - first > index) {
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const pos = (viewport.first - 1) * this.itemSize;
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horizontal ? scrollTo(pos, 0) : scrollTo(0, pos);
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}
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}
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} else if (isToEnd) {
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if (both) {
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if (viewport.last.rows - first.rows <= index[0] + 1) {
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scrollTo(viewport.first.cols * this.itemSize[1], (viewport.first.rows + 1) * this.itemSize[0]);
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} else if (viewport.last.cols - first.cols <= index[1] + 1) {
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scrollTo((viewport.first.cols + 1) * this.itemSize[1], viewport.first.rows * this.itemSize[0]);
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}
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} else {
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if (viewport.last - first <= index + 1) {
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const pos = (viewport.first + 1) * this.itemSize;
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horizontal ? scrollTo(pos, 0) : scrollTo(0, pos);
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}
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}
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}
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} else {
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this.scrollToIndex(index, behavior);
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}
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},
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getRenderedRange() {
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const calculateFirstInViewport = (_pos, _size) => Math.floor(_pos / (_size || _pos));
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let firstInViewport = this.first;
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let lastInViewport = 0;
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if (this.element) {
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const both = this.isBoth();
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const horizontal = this.isHorizontal();
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const { scrollTop, scrollLeft } = this.element.scrollTop;
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if (both) {
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firstInViewport = { rows: calculateFirstInViewport(scrollTop, this.itemSize[0]), cols: calculateFirstInViewport(scrollLeft, this.itemSize[1]) };
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lastInViewport = { rows: firstInViewport.rows + this.numItemsInViewport.rows, cols: firstInViewport.cols + this.numItemsInViewport.cols };
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} else {
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const scrollPos = horizontal ? scrollLeft : scrollTop;
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firstInViewport = calculateFirstInViewport(scrollPos, this.itemSize);
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lastInViewport = firstInViewport + this.numItemsInViewport;
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}
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}
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return {
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first: this.first,
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last: this.last,
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viewport: {
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first: firstInViewport,
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last: lastInViewport
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}
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};
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},
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calculateNumItems() {
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const both = this.isBoth();
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const horizontal = this.isHorizontal();
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const itemSize = this.itemSize;
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const contentPos = this.getContentPosition();
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const contentWidth = this.element ? this.element.offsetWidth - contentPos.left : 0;
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const contentHeight = this.element ? this.element.offsetHeight - contentPos.top : 0;
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const calculateNumItemsInViewport = (_contentSize, _itemSize) => Math.ceil(_contentSize / (_itemSize || _contentSize));
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const calculateNumToleratedItems = (_numItems) => Math.ceil(_numItems / 2);
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const numItemsInViewport = both
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? { rows: calculateNumItemsInViewport(contentHeight, itemSize[0]), cols: calculateNumItemsInViewport(contentWidth, itemSize[1]) }
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: calculateNumItemsInViewport(horizontal ? contentWidth : contentHeight, itemSize);
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const numToleratedItems = this.d_numToleratedItems || (both ? [calculateNumToleratedItems(numItemsInViewport.rows), calculateNumToleratedItems(numItemsInViewport.cols)] : calculateNumToleratedItems(numItemsInViewport));
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return { numItemsInViewport, numToleratedItems };
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},
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calculateOptions() {
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const both = this.isBoth();
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const first = this.first;
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const { numItemsInViewport, numToleratedItems } = this.calculateNumItems();
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const calculateLast = (_first, _num, _numT, _isCols = false) => this.getLast(_first + _num + (_first < _numT ? 2 : 3) * _numT, _isCols);
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const last = both
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? { rows: calculateLast(first.rows, numItemsInViewport.rows, numToleratedItems[0]), cols: calculateLast(first.cols, numItemsInViewport.cols, numToleratedItems[1], true) }
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: calculateLast(first, numItemsInViewport, numToleratedItems);
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this.last = last;
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this.numItemsInViewport = numItemsInViewport;
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this.d_numToleratedItems = numToleratedItems;
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this.$emit('update:numToleratedItems', this.d_numToleratedItems);
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if (this.showLoader) {
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this.loaderArr = both ? Array.from({ length: numItemsInViewport.rows }).map(() => Array.from({ length: numItemsInViewport.cols })) : Array.from({ length: numItemsInViewport });
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}
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if (this.lazy) {
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Promise.resolve().then(() => {
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this.lazyLoadState = {
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first: this.step ? (both ? { rows: 0, cols: first.cols } : 0) : first,
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last: Math.min(this.step ? this.step : last, this.items.length)
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};
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this.$emit('lazy-load', this.lazyLoadState);
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});
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}
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},
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calculateAutoSize() {
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if (this.autoSize && !this.d_loading) {
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Promise.resolve().then(() => {
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if (this.content) {
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const both = this.isBoth();
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const horizontal = this.isHorizontal();
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const vertical = this.isVertical();
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this.content.style.minHeight = this.content.style.minWidth = 'auto';
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this.content.style.position = 'relative';
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this.element.style.contain = 'none';
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const [contentWidth, contentHeight] = [DomHandler.getWidth(this.content), DomHandler.getHeight(this.content)];
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contentWidth !== this.defaultContentWidth && (this.element.style.width = '');
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contentHeight !== this.defaultContentHeight && (this.element.style.height = '');
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const [width, height] = [DomHandler.getWidth(this.element), DomHandler.getHeight(this.element)];
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(both || horizontal) && (this.element.style.width = width < this.defaultWidth ? width + 'px' : this.scrollWidth || this.defaultWidth + 'px');
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(both || vertical) && (this.element.style.height = height < this.defaultHeight ? height + 'px' : this.scrollHeight || this.defaultHeight + 'px');
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this.content.style.minHeight = this.content.style.minWidth = '';
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this.content.style.position = '';
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this.element.style.contain = '';
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}
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});
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}
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},
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getLast(last = 0, isCols) {
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return this.items ? Math.min(isCols ? (this.columns || this.items[0]).length : this.items.length, last) : 0;
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},
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getContentPosition() {
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if (this.content) {
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const style = getComputedStyle(this.content);
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const left = parseFloat(style.paddingLeft) + Math.max(parseFloat(style.left) || 0, 0);
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const right = parseFloat(style.paddingRight) + Math.max(parseFloat(style.right) || 0, 0);
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const top = parseFloat(style.paddingTop) + Math.max(parseFloat(style.top) || 0, 0);
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const bottom = parseFloat(style.paddingBottom) + Math.max(parseFloat(style.bottom) || 0, 0);
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return { left, right, top, bottom, x: left + right, y: top + bottom };
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}
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return { left: 0, right: 0, top: 0, bottom: 0, x: 0, y: 0 };
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},
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setSize() {
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if (this.element) {
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const both = this.isBoth();
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const horizontal = this.isHorizontal();
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const parentElement = this.element.parentElement;
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const width = this.scrollWidth || `${this.element.offsetWidth || parentElement.offsetWidth}px`;
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const height = this.scrollHeight || `${this.element.offsetHeight || parentElement.offsetHeight}px`;
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const setProp = (_name, _value) => (this.element.style[_name] = _value);
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if (both || horizontal) {
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setProp('height', height);
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setProp('width', width);
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} else {
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setProp('height', height);
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}
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}
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},
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setSpacerSize() {
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const items = this.items;
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if (items) {
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const both = this.isBoth();
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const horizontal = this.isHorizontal();
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const contentPos = this.getContentPosition();
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const setProp = (_name, _value, _size, _cpos = 0) => (this.spacerStyle = { ...this.spacerStyle, ...{ [`${_name}`]: (_value || []).length * _size + _cpos + 'px' } });
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if (both) {
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setProp('height', items, this.itemSize[0], contentPos.y);
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setProp('width', this.columns || items[1], this.itemSize[1], contentPos.x);
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} else {
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horizontal ? setProp('width', this.columns || items, this.itemSize, contentPos.x) : setProp('height', items, this.itemSize, contentPos.y);
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}
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}
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},
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setContentPosition(pos) {
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if (this.content && !this.appendOnly) {
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const both = this.isBoth();
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const horizontal = this.isHorizontal();
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const first = pos ? pos.first : this.first;
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const calculateTranslateVal = (_first, _size) => _first * _size;
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const setTransform = (_x = 0, _y = 0) => (this.contentStyle = { ...this.contentStyle, ...{ transform: `translate3d(${_x}px, ${_y}px, 0)` } });
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if (both) {
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setTransform(calculateTranslateVal(first.cols, this.itemSize[1]), calculateTranslateVal(first.rows, this.itemSize[0]));
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} else {
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const translateVal = calculateTranslateVal(first, this.itemSize);
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horizontal ? setTransform(translateVal, 0) : setTransform(0, translateVal);
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}
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}
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},
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onScrollPositionChange(event) {
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const target = event.target;
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const both = this.isBoth();
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const horizontal = this.isHorizontal();
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const contentPos = this.getContentPosition();
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const calculateScrollPos = (_pos, _cpos) => (_pos ? (_pos > _cpos ? _pos - _cpos : _pos) : 0);
|
|
const calculateCurrentIndex = (_pos, _size) => Math.floor(_pos / (_size || _pos));
|
|
|
|
const calculateTriggerIndex = (_currentIndex, _first, _last, _num, _numT, _isScrollDownOrRight) => {
|
|
return _currentIndex <= _numT ? _numT : _isScrollDownOrRight ? _last - _num - _numT : _first + _numT - 1;
|
|
};
|
|
|
|
const calculateFirst = (_currentIndex, _triggerIndex, _first, _last, _num, _numT, _isScrollDownOrRight) => {
|
|
if (_currentIndex <= _numT) return 0;
|
|
else return Math.max(0, _isScrollDownOrRight ? (_currentIndex < _triggerIndex ? _first : _currentIndex - _numT) : _currentIndex > _triggerIndex ? _first : _currentIndex - 2 * _numT);
|
|
};
|
|
|
|
const calculateLast = (_currentIndex, _first, _last, _num, _numT, _isCols) => {
|
|
let lastValue = _first + _num + 2 * _numT;
|
|
|
|
if (_currentIndex >= _numT) {
|
|
lastValue += _numT + 1;
|
|
}
|
|
|
|
return this.getLast(lastValue, _isCols);
|
|
};
|
|
|
|
const scrollTop = calculateScrollPos(target.scrollTop, contentPos.top);
|
|
const scrollLeft = calculateScrollPos(target.scrollLeft, contentPos.left);
|
|
|
|
let newFirst = both ? { rows: 0, cols: 0 } : 0;
|
|
let newLast = this.last;
|
|
let isRangeChanged = false;
|
|
let newScrollPos = this.lastScrollPos;
|
|
|
|
if (both) {
|
|
const isScrollDown = this.lastScrollPos.top <= scrollTop;
|
|
const isScrollRight = this.lastScrollPos.left <= scrollLeft;
|
|
|
|
if (!this.appendOnly || (this.appendOnly && (isScrollDown || isScrollRight))) {
|
|
const currentIndex = { rows: calculateCurrentIndex(scrollTop, this.itemSize[0]), cols: calculateCurrentIndex(scrollLeft, this.itemSize[1]) };
|
|
const triggerIndex = {
|
|
rows: calculateTriggerIndex(currentIndex.rows, this.first.rows, this.last.rows, this.numItemsInViewport.rows, this.d_numToleratedItems[0], isScrollDown),
|
|
cols: calculateTriggerIndex(currentIndex.cols, this.first.cols, this.last.cols, this.numItemsInViewport.cols, this.d_numToleratedItems[1], isScrollRight)
|
|
};
|
|
|
|
newFirst = {
|
|
rows: calculateFirst(currentIndex.rows, triggerIndex.rows, this.first.rows, this.last.rows, this.numItemsInViewport.rows, this.d_numToleratedItems[0], isScrollDown),
|
|
cols: calculateFirst(currentIndex.cols, triggerIndex.cols, this.first.cols, this.last.cols, this.numItemsInViewport.cols, this.d_numToleratedItems[1], isScrollRight)
|
|
};
|
|
newLast = {
|
|
rows: calculateLast(currentIndex.rows, newFirst.rows, this.last.rows, this.numItemsInViewport.rows, this.d_numToleratedItems[0]),
|
|
cols: calculateLast(currentIndex.cols, newFirst.cols, this.last.cols, this.numItemsInViewport.cols, this.d_numToleratedItems[1], true)
|
|
};
|
|
|
|
isRangeChanged = newFirst.rows !== this.first.rows || newLast.rows !== this.last.rows || newFirst.cols !== this.first.cols || newLast.cols !== this.last.cols || this.isRangeChanged;
|
|
newScrollPos = { top: scrollTop, left: scrollLeft };
|
|
}
|
|
} else {
|
|
const scrollPos = horizontal ? scrollLeft : scrollTop;
|
|
const isScrollDownOrRight = this.lastScrollPos <= scrollPos;
|
|
|
|
if (!this.appendOnly || (this.appendOnly && isScrollDownOrRight)) {
|
|
const currentIndex = calculateCurrentIndex(scrollPos, this.itemSize);
|
|
const triggerIndex = calculateTriggerIndex(currentIndex, this.first, this.last, this.numItemsInViewport, this.d_numToleratedItems, isScrollDownOrRight);
|
|
|
|
newFirst = calculateFirst(currentIndex, triggerIndex, this.first, this.last, this.numItemsInViewport, this.d_numToleratedItems, isScrollDownOrRight);
|
|
newLast = calculateLast(currentIndex, newFirst, this.last, this.numItemsInViewport, this.d_numToleratedItems);
|
|
isRangeChanged = newFirst !== this.first || newLast !== this.last || this.isRangeChanged;
|
|
newScrollPos = scrollPos;
|
|
}
|
|
}
|
|
|
|
return {
|
|
first: newFirst,
|
|
last: newLast,
|
|
isRangeChanged,
|
|
scrollPos: newScrollPos
|
|
};
|
|
},
|
|
onScrollChange(event) {
|
|
const { first, last, isRangeChanged, scrollPos } = this.onScrollPositionChange(event);
|
|
|
|
if (isRangeChanged) {
|
|
const newState = { first, last };
|
|
|
|
this.setContentPosition(newState);
|
|
|
|
this.first = first;
|
|
this.last = last;
|
|
this.lastScrollPos = scrollPos;
|
|
|
|
this.$emit('scroll-index-change', newState);
|
|
|
|
if (this.lazy && this.isPageChanged(first)) {
|
|
const lazyLoadState = {
|
|
first: this.step ? Math.min(this.getPageByFirst(first) * this.step, this.items.length - this.step) : first,
|
|
last: Math.min(this.step ? (this.getPageByFirst(first) + 1) * this.step : last, this.items.length)
|
|
};
|
|
const isLazyStateChanged = this.lazyLoadState.first !== lazyLoadState.first || this.lazyLoadState.last !== lazyLoadState.last;
|
|
|
|
isLazyStateChanged && this.$emit('lazy-load', lazyLoadState);
|
|
this.lazyLoadState = lazyLoadState;
|
|
}
|
|
}
|
|
},
|
|
onScroll(event) {
|
|
this.$emit('scroll', event);
|
|
|
|
if (this.delay && this.isPageChanged()) {
|
|
if (this.scrollTimeout) {
|
|
clearTimeout(this.scrollTimeout);
|
|
}
|
|
|
|
if (!this.d_loading && this.showLoader) {
|
|
const { isRangeChanged } = this.onScrollPositionChange(event);
|
|
const changed = isRangeChanged || (this.step ? this.isPageChanged() : false);
|
|
|
|
changed && (this.d_loading = true);
|
|
}
|
|
|
|
this.scrollTimeout = setTimeout(() => {
|
|
this.onScrollChange(event);
|
|
|
|
if (this.d_loading && this.showLoader && (!this.lazy || this.loading === undefined)) {
|
|
this.d_loading = false;
|
|
this.page = this.getPageByFirst();
|
|
}
|
|
}, this.delay);
|
|
} else {
|
|
this.onScrollChange(event);
|
|
}
|
|
},
|
|
onResize() {
|
|
if (this.resizeTimeout) {
|
|
clearTimeout(this.resizeTimeout);
|
|
}
|
|
|
|
this.resizeTimeout = setTimeout(() => {
|
|
if (DomHandler.isVisible(this.element)) {
|
|
const both = this.isBoth();
|
|
const vertical = this.isVertical();
|
|
const horizontal = this.isHorizontal();
|
|
const [width, height] = [DomHandler.getWidth(this.element), DomHandler.getHeight(this.element)];
|
|
const [isDiffWidth, isDiffHeight] = [width !== this.defaultWidth, height !== this.defaultHeight];
|
|
const reinit = both ? isDiffWidth || isDiffHeight : horizontal ? isDiffWidth : vertical ? isDiffHeight : false;
|
|
|
|
if (reinit) {
|
|
this.d_numToleratedItems = this.numToleratedItems;
|
|
this.defaultWidth = width;
|
|
this.defaultHeight = height;
|
|
this.defaultContentWidth = DomHandler.getWidth(this.content);
|
|
this.defaultContentHeight = DomHandler.getHeight(this.content);
|
|
|
|
this.init();
|
|
}
|
|
}
|
|
}, this.resizeDelay);
|
|
},
|
|
bindResizeListener() {
|
|
if (!this.resizeListener) {
|
|
this.resizeListener = this.onResize.bind(this);
|
|
|
|
window.addEventListener('resize', this.resizeListener);
|
|
window.addEventListener('orientationchange', this.resizeListener);
|
|
}
|
|
},
|
|
unbindResizeListener() {
|
|
if (this.resizeListener) {
|
|
window.removeEventListener('resize', this.resizeListener);
|
|
window.removeEventListener('orientationchange', this.resizeListener);
|
|
this.resizeListener = null;
|
|
}
|
|
},
|
|
getOptions(renderedIndex) {
|
|
const count = (this.items || []).length;
|
|
const index = this.isBoth() ? this.first.rows + renderedIndex : this.first + renderedIndex;
|
|
|
|
return {
|
|
index,
|
|
count,
|
|
first: index === 0,
|
|
last: index === count - 1,
|
|
even: index % 2 === 0,
|
|
odd: index % 2 !== 0
|
|
};
|
|
},
|
|
getLoaderOptions(index, extOptions) {
|
|
let count = this.loaderArr.length;
|
|
|
|
return {
|
|
index,
|
|
count,
|
|
first: index === 0,
|
|
last: index === count - 1,
|
|
even: index % 2 === 0,
|
|
odd: index % 2 !== 0,
|
|
...extOptions
|
|
};
|
|
},
|
|
getPageByFirst(first) {
|
|
return Math.floor(((first ?? this.first) + this.d_numToleratedItems * 4) / (this.step || 1));
|
|
},
|
|
isPageChanged(first) {
|
|
return this.step ? this.page !== this.getPageByFirst(first ?? this.first) : true;
|
|
},
|
|
setContentEl(el) {
|
|
this.content = el || this.content || DomHandler.findSingle(this.element, '.p-virtualscroller-content');
|
|
},
|
|
elementRef(el) {
|
|
this.element = el;
|
|
},
|
|
contentRef(el) {
|
|
this.content = el;
|
|
}
|
|
},
|
|
computed: {
|
|
containerClass() {
|
|
return [
|
|
'p-virtualscroller',
|
|
{
|
|
'p-virtualscroller-inline': this.inline,
|
|
'p-virtualscroller-both p-both-scroll': this.isBoth(),
|
|
'p-virtualscroller-horizontal p-horizontal-scroll': this.isHorizontal()
|
|
},
|
|
this.class
|
|
];
|
|
},
|
|
contentClass() {
|
|
return [
|
|
'p-virtualscroller-content',
|
|
{
|
|
'p-virtualscroller-loading': this.d_loading
|
|
}
|
|
];
|
|
},
|
|
loaderClass() {
|
|
return [
|
|
'p-virtualscroller-loader',
|
|
{
|
|
'p-component-overlay': !this.$slots.loader
|
|
}
|
|
];
|
|
},
|
|
loadedItems() {
|
|
if (this.items && !this.d_loading) {
|
|
if (this.isBoth()) return this.items.slice(this.appendOnly ? 0 : this.first.rows, this.last.rows).map((item) => (this.columns ? item : item.slice(this.appendOnly ? 0 : this.first.cols, this.last.cols)));
|
|
else if (this.isHorizontal() && this.columns) return this.items;
|
|
else return this.items.slice(this.appendOnly ? 0 : this.first, this.last);
|
|
}
|
|
|
|
return [];
|
|
},
|
|
loadedRows() {
|
|
return this.d_loading ? (this.loaderDisabled ? this.loaderArr : []) : this.loadedItems;
|
|
},
|
|
loadedColumns() {
|
|
if (this.columns) {
|
|
const both = this.isBoth();
|
|
const horizontal = this.isHorizontal();
|
|
|
|
if (both || horizontal) {
|
|
return this.d_loading && this.loaderDisabled ? (both ? this.loaderArr[0] : this.loaderArr) : this.columns.slice(both ? this.first.cols : this.first, both ? this.last.cols : this.last);
|
|
}
|
|
}
|
|
|
|
return this.columns;
|
|
}
|
|
}
|
|
};
|
|
</script>
|
|
|
|
<style>
|
|
.p-virtualscroller {
|
|
position: relative;
|
|
overflow: auto;
|
|
contain: strict;
|
|
transform: translateZ(0);
|
|
will-change: scroll-position;
|
|
outline: 0 none;
|
|
}
|
|
|
|
.p-virtualscroller-content {
|
|
position: absolute;
|
|
top: 0;
|
|
left: 0;
|
|
/* contain: content; */
|
|
min-height: 100%;
|
|
min-width: 100%;
|
|
will-change: transform;
|
|
}
|
|
|
|
.p-virtualscroller-spacer {
|
|
position: absolute;
|
|
top: 0;
|
|
left: 0;
|
|
height: 1px;
|
|
width: 1px;
|
|
transform-origin: 0 0;
|
|
pointer-events: none;
|
|
}
|
|
|
|
.p-virtualscroller .p-virtualscroller-loader {
|
|
position: sticky;
|
|
top: 0;
|
|
left: 0;
|
|
width: 100%;
|
|
height: 100%;
|
|
}
|
|
|
|
.p-virtualscroller-loader.p-component-overlay {
|
|
display: flex;
|
|
align-items: center;
|
|
justify-content: center;
|
|
}
|
|
|
|
.p-virtualscroller-loading-icon {
|
|
font-size: 2rem;
|
|
}
|
|
|
|
.p-virtualscroller-horizontal > .p-virtualscroller-content {
|
|
display: flex;
|
|
}
|
|
|
|
/* Inline */
|
|
.p-virtualscroller-inline .p-virtualscroller-content {
|
|
position: static;
|
|
}
|
|
</style>
|