[improvement] Collapse: jsx (#2501)

packages/collapse/index.js

@@ -0,0 +1,32 @@
+import { use } from '../utils';
+
+const [sfc, bem] = use('collapse');
+
+export default sfc({
+  props: {
+    accordion: Boolean,
+    value: [String, Number, Array]
+  },
+
+  data() {
+    return {
+      items: []
+    };
+  },
+
+  methods: {
+    switch(name, expanded) {
+      if (!this.accordion) {
+        name = expanded
+          ? this.value.concat(name)
+          : this.value.filter(activeName => activeName !== name);
+      }
+      this.$emit('change', name);
+      this.$emit('input', name);
+    }
+  },
+
+  render(h) {
+    return <div class={[bem(), 'van-hairline--top-bottom']}>{this.$slots.default}</div>;
+  }
+});