[new feature] add List component (#682)

packages/list/index.vue

@@ -0,0 +1,118 @@
+<template>
+  <div class="van-list">
+    <slot />
+    <div class="van-list__loading" v-show="loading">
+      <slot name="loading">
+        <loading />
+        <span class="van-list__loading-text">{{ $t('loadingTip') }}</span>
+      </slot>
+    </div>
+  </div>
+</template>
+
+<script>
+import create from '../utils/create';
+import utils from '../utils/scroll';
+import { on, off } from '../utils/event';
+
+export default create({
+  name: 'van-list',
+
+  model: {
+    prop: 'loading'
+  },
+
+  props: {
+    loading: Boolean,
+    finished: Boolean,
+    immediateCheck: {
+      type: Boolean,
+      default: true
+    },
+    offset: {
+      type: Number,
+      default: 300
+    }
+  },
+
+  mounted() {
+    this.scroller = utils.getScrollEventTarget(this.$el);
+    this.handler(true);
+
+    if (this.immediateCheck) {
+      this.$nextTick(this.onScroll);
+    }
+  },
+
+  destroyed() {
+    this.handler(false);
+  },
+
+  activated() {
+    /* istanbul ignore next */
+    this.handler(true);
+  },
+
+  deactivated() {
+    /* istanbul ignore next */
+    this.handler(false);
+  },
+
+  watch: {
+    loading() {
+      this.$nextTick(this.onScroll);
+    },
+
+    finished() {
+      this.$nextTick(this.onScroll);
+    }
+  },
+
+  methods: {
+    onScroll() {
+      if (this.loading || this.finished) {
+        return;
+      }
+
+      const el = this.$el;
+      const { scroller } = this;
+      const scrollerHeight = utils.getVisibleHeight(scroller);
+
+      /* istanbul ignore next */
+      if (!scrollerHeight) {
+        return;
+      }
+
+      const scrollTop = utils.getScrollTop(scroller);
+      const targetBottom = scrollTop + scrollerHeight;
+
+      let reachBottom = false;
+
+      /* istanbul ignore next */
+      if (el === scroller) {
+        reachBottom = scroller.scrollHeight - targetBottom < this.offset;
+      } else {
+        const elBottom =
+          utils.getElementTop(el) -
+          utils.getElementTop(scroller) +
+          utils.getVisibleHeight(el);
+        reachBottom = elBottom - scrollerHeight < this.offset;
+      }
+
+      /* istanbul ignore else */
+      if (reachBottom) {
+        this.$emit('input', true);
+        this.$emit('load');
+      }
+    },
+
+    handler(bind) {
+      /* istanbul ignore else */
+      if (this.binded !== bind) {
+        this.binded = bind;
+        (bind ? on : off)(this.scroller, 'scroll', this.onScroll);
+      }
+    }
+  }
+});
+</script>