first

packages/infinite-scroll/index.js

@@ -0,0 +1,8 @@
+import InfiniteScroll from './src/main.js';
+
+/* istanbul ignore next */
+InfiniteScroll.install = function(Vue) {
+  Vue.directive(InfiniteScroll.name, InfiniteScroll);
+};
+
+export default InfiniteScroll;

packages/infinite-scroll/src/main.js

@@ -0,0 +1,150 @@
+import throttle from 'throttle-debounce/debounce';
+import {
+  isHtmlElement,
+  isFunction,
+  isUndefined,
+  isDefined
+} from 'element-ui/src/utils/types';
+import {
+  getScrollContainer
+} from 'element-ui/src/utils/dom';
+
+const getStyleComputedProperty = (element, property) => {
+  if (element === window) {
+    element = document.documentElement;
+  }
+
+  if (element.nodeType !== 1) {
+    return [];
+  }
+  // NOTE: 1 DOM access here
+  const css = window.getComputedStyle(element, null);
+  return property ? css[property] : css;
+};
+
+const entries = (obj) => {
+  return Object.keys(obj || {})
+    .map(key => ([key, obj[key]]));
+};
+
+const getPositionSize = (el, prop) => {
+  return el === window || el === document
+    ? document.documentElement[prop]
+    : el[prop];
+};
+
+const getOffsetHeight = el => {
+  return getPositionSize(el, 'offsetHeight');
+};
+
+const getClientHeight = el => {
+  return getPositionSize(el, 'clientHeight');
+};
+
+const scope = 'ElInfiniteScroll';
+const attributes = {
+  delay: {
+    type: Number,
+    default: 200
+  },
+  distance: {
+    type: Number,
+    default: 0
+  },
+  disabled: {
+    type: Boolean,
+    default: false
+  },
+  immediate: {
+    type: Boolean,
+    default: true
+  }
+};
+
+const getScrollOptions = (el, vm) => {
+  if (!isHtmlElement(el)) return {};
+
+  return entries(attributes).reduce((map, [key, option]) => {
+    const { type, default: defaultValue } = option;
+    let value = el.getAttribute(`infinite-scroll-${key}`);
+    value = isUndefined(vm[value]) ? value : vm[value];
+    switch (type) {
+      case Number:
+        value = Number(value);
+        value = Number.isNaN(value) ? defaultValue : value;
+        break;
+      case Boolean:
+        value = isDefined(value) ? value === 'false' ? false : Boolean(value) : defaultValue;
+        break;
+      default:
+        value = type(value);
+    }
+    map[key] = value;
+    return map;
+  }, {});
+};
+
+const getElementTop = el => el.getBoundingClientRect().top;
+
+const handleScroll = function(cb) {
+  const { el, vm, container, observer } = this[scope];
+  const { distance, disabled } = getScrollOptions(el, vm);
+
+  if (disabled) return;
+
+  const containerInfo = container.getBoundingClientRect();
+  if (!containerInfo.width && !containerInfo.height) return;
+
+  let shouldTrigger = false;
+
+  if (container === el) {
+    // be aware of difference between clientHeight & offsetHeight & window.getComputedStyle().height
+    const scrollBottom = container.scrollTop + getClientHeight(container);
+    shouldTrigger = container.scrollHeight - scrollBottom <= distance;
+  } else {
+    const heightBelowTop = getOffsetHeight(el) + getElementTop(el) - getElementTop(container);
+    const offsetHeight = getOffsetHeight(container);
+    const borderBottom = Number.parseFloat(getStyleComputedProperty(container, 'borderBottomWidth'));
+    shouldTrigger = heightBelowTop - offsetHeight + borderBottom <= distance;
+  }
+
+  if (shouldTrigger && isFunction(cb)) {
+    cb.call(vm);
+  } else if (observer) {
+    observer.disconnect();
+    this[scope].observer = null;
+  }
+
+};
+
+export default {
+  name: 'InfiniteScroll',
+  inserted(el, binding, vnode) {
+    const cb = binding.value;
+
+    const vm = vnode.context;
+    // only include vertical scroll
+    const container = getScrollContainer(el, true);
+    const { delay, immediate } = getScrollOptions(el, vm);
+    const onScroll = throttle(delay, handleScroll.bind(el, cb));
+
+    el[scope] = { el, vm, container, onScroll };
+
+    if (container) {
+      container.addEventListener('scroll', onScroll);
+
+      if (immediate) {
+        const observer = el[scope].observer = new MutationObserver(onScroll);
+        observer.observe(container, { childList: true, subtree: true });
+        onScroll();
+      }
+    }
+  },
+  unbind(el) {
+    const { container, onScroll } = el[scope];
+    if (container) {
+      container.removeEventListener('scroll', onScroll);
+    }
+  }
+};
+