[improvement] rename packages dir to src (#3659)

src/index-anchor/index.js

@@ -0,0 +1,60 @@
+import { createNamespace } from '../utils';
+import { ChildrenMixin } from '../mixins/relation';
+
+const [createComponent, bem] = createNamespace('index-anchor');
+
+export default createComponent({
+  mixins: [ChildrenMixin('vanIndexBar', { indexKey: 'childrenIndex' })],
+
+  props: {
+    index: [String, Number]
+  },
+
+  data() {
+    return {
+      top: 0,
+      active: false
+    };
+  },
+
+  computed: {
+    sticky() {
+      return this.active && this.parent.sticky;
+    },
+
+    anchorStyle() {
+      if (this.sticky) {
+        return {
+          transform: `translate3d(0, ${this.top}px, 0)`,
+          color: this.parent.highlightColor,
+          zIndex: `${this.parent.zIndex}`
+        };
+      }
+    }
+  },
+
+  mounted() {
+    this.height = this.$el.offsetHeight;
+  },
+
+  methods: {
+    scrollIntoView() {
+      this.$el.scrollIntoView();
+    }
+  },
+
+  render(h) {
+    const { sticky } = this;
+
+    return (
+      <div style={{ height: sticky ? `${this.height}px` : null }}>
+        <div
+          style={this.anchorStyle}
+          class={[bem({ sticky }), { 'van-hairline--bottom': sticky }]}
+        >
+          {this.slots('default') || this.index}
+        </div>
+      </div>
+    );
+  }
+});