add anchor component

src/components/anchor/anchor.vue

@@ -0,0 +1,189 @@
+<template>
+    <component :is="wrapperComponent" :offset-top="offsetTop" :offset-bottom="offsetBottom" @on-change="handleAffixStateChange">
+		<div :class="`${prefix}-wrapper`" :style="wrapperStyle">
+            <div :class="`${prefix}`">
+                <div :class="`${prefix}-ink`">
+                    <span v-show="showInkBall" :class="`${prefix}-ink-ball`" :style="{top: `${inkTop}px`}"></span>
+                </div>
+                <slot></slot>
+            </div>
+        </div>
+	</component>
+</template>
+<script>
+import { scrollTop, findComponentDownward, findComponentsDownward, sharpMatcherRegx } from '../../utils/assist';
+import { on, off } from '../../utils/dom';
+export default {
+    name: 'Anchor',
+    data () {
+        return {
+            prefix: 'ivu-anchor',
+            isAffixed: false, // current affixed state
+            inkTop: 0,
+            linkHeight: 0,
+            animating: false, // if is scrolling now
+            currentLink: '', // current show link =>  #href -> currentLink = #href
+            currentId: '', // current show title id =>  #href -> currentId = href
+            scrollContainer: null,
+            scrollElement: null,
+            titlesOffsetArr: [],
+            wrapperTop: 0,
+            upperFirstTitle: true
+        };
+    },
+    props: {
+        affix: {
+            type: Boolean,
+            default: true
+        },
+        offsetTop: {
+            type: Number,
+            default: 0
+        },
+        offsetBottom: Number,
+        bounds: {
+            type: Number,
+            default: 5
+        },
+        container: [String, HTMLElement],
+        showInkInFixed: {
+            type: Boolean,
+            default: false
+        }
+    },
+    computed: {
+        wrapperComponent () {
+            return this.affix ? 'Affix' : 'div';
+        },
+        wrapperStyle () {
+            return {
+                maxHeight: this.offsetTop ? `calc(100vh - ${this.offsetTop}px)` : '100vh'
+            };
+        },
+        containerIsWindow () {
+            return this.scrollContainer === window;
+        },
+        showInkBall () {
+            return this.showInkInFixed && (this.isAffixed || (!this.isAffixed && !this.upperFirstTitle && this.scrollContainer !== window));
+        }
+    },
+    methods: {
+        handleAffixStateChange (state) {
+            this.isAffixed = this.affix && state;
+        },
+        handleScroll (e) {
+            this.upperFirstTitle = e.target.scrollTop < this.titlesOffsetArr[0].offset;
+            if (this.animating) return;
+            this.updateTitleOffset();
+            const scrollTop = document.documentElement.scrollTop || document.body.scrollTop || e.target.scrollTop;
+            this.getCurrentScrollAtTitleId(scrollTop);
+        },
+        turnTo (href) {
+            const oldHref = this.currentLink;
+            this.currentLink = href;
+            this.$router.push({
+                path: href
+            });
+            this.$emit('on-select', href);
+        },
+        handleHashChange () {
+            const url = window.location.href;
+            const sharpLinkMatch = sharpMatcherRegx.exec(url);
+            this.currentLink = sharpLinkMatch[0];
+            this.currentId = sharpLinkMatch[1];
+        },
+        handleScrollTo () {
+            const anchor = document.getElementById(this.currentId);
+            if (!anchor) return;
+            const offsetTop = anchor.offsetTop - this.wrapperTop;
+            this.animating = true;
+            scrollTop(this.scrollContainer, this.scrollElement.scrollTop, offsetTop, 600, () => {
+                this.animating = false;
+            });
+            this.handleSetInkTop();
+        },
+        handleSetInkTop () {
+            const currentLinkElementA = document.querySelector(`a[data-href="${this.currentLink}"]`);
+            if (!currentLinkElementA) return;
+            const elementATop = currentLinkElementA.offsetTop;
+            const top = (elementATop < 0 ? this.offsetTop : elementATop);
+            this.inkTop = top;
+        },
+        updateTitleOffset () {
+            const links = findComponentsDownward(this, 'AnchorLink').map(link => {
+                return link.href;
+            });
+            const offsetArr = links.map(link => {
+                const id = link.split('#')[1];
+                const titleEle = document.getElementById(id);
+                return {
+                    link: link,
+                    offset: titleEle.offsetTop - this.scrollElement.offsetTop
+                };
+            });
+            this.titlesOffsetArr = offsetArr;
+        },
+        getCurrentScrollAtTitleId (scrollTop) {
+            let i = -1;
+            let len = this.titlesOffsetArr.length;
+            let titleItem = {
+                link: '#',
+                offset: 0
+            };
+            scrollTop += this.bounds;
+            while (++i < len) {
+                let currentEle = this.titlesOffsetArr[i];
+                let nextEle = this.titlesOffsetArr[i + 1];
+                if (scrollTop >= currentEle.offset && scrollTop < ((nextEle && nextEle.offset) || Infinity)) {
+                    titleItem = this.titlesOffsetArr[i];
+                    break;
+                }
+            }
+            this.currentLink = titleItem.link;
+            this.handleSetInkTop();
+        },
+        getContainer () {
+            this.scrollContainer = this.container ? (typeof this.container === 'string' ? document.querySelector(this.container) : this.container) : window;
+            this.scrollElement = this.container ? this.scrollContainer : (document.documentElement || document.body);
+        },
+        removeListener () {
+            off(this.scrollContainer, 'scroll', this.handleScroll);
+            off(window, 'hashchange', this.handleHashChange);
+        },
+        init () {
+            const anchorLink = findComponentDownward(this, 'AnchorLink');
+            this.linkHeight = anchorLink ? anchorLink.$el.getBoundingClientRect().height : 0;
+            this.handleHashChange();
+            this.$nextTick(() => {
+                this.removeListener();
+                this.getContainer();
+                this.wrapperTop = this.containerIsWindow ? 0 : this.scrollElement.offsetTop;
+                this.handleScrollTo();
+                this.handleSetInkTop();
+                this.updateTitleOffset();
+                this.upperFirstTitle = this.scrollElement.scrollTop < this.titlesOffsetArr[0].offset;
+                on(this.scrollContainer, 'scroll', this.handleScroll);
+                on(window, 'hashchange', this.handleHashChange);
+            });
+        }
+    },
+    watch: {
+        '$route' () {
+            this.handleHashChange();
+            this.handleScrollTo();
+        },
+        container () {
+            this.init();
+        },
+        currentLink (newHref, oldHref) {
+            this.$emit('on-change', newHref, oldHref);
+        }
+    },
+    mounted () {
+        this.init()
+    },
+    beforeDestroy () {
+        this.removeListener();
+    }
+};
+</script>