[improvement] Rate: support touch move select (#1951)

packages/rate/index.vue

@@ -1,11 +1,12 @@
 <template>
-  <div :class="b()">
+  <div :class="b()" @touchmove="onTouchMove">
     <svg
       v-for="(isFull, index) in list"
       :fill="disabled ? disabledColor : isFull ? color : voidColor"
       viewBox="0 0 32 32"
       :style="style"
       :class="b('item')"
+      :data-index="index"
       @click="onSelect(index)"
     >
       <path :d="isFull ? 'M32 12.408l-11.056-1.607-4.944-10.018-4.944 10.018-11.056 1.607 8 7.798-1.889 11.011 9.889-5.199 9.889 5.199-1.889-11.011 8-7.798z' : 'M32 12.408l-11.056-1.607-4.944-10.018-4.944 10.018-11.056 1.607 8 7.798-1.889 11.011 9.889-5.199 9.889 5.199-1.889-11.011 8-7.798zM16 23.547l-6.983 3.671 1.334-7.776-5.65-5.507 7.808-1.134 3.492-7.075 3.492 7.075 7.807 1.134-5.65 5.507 1.334 7.776-6.983-3.671z'" />
@@ -66,6 +67,24 @@ export default create({
         this.$emit('input', index + 1);
         this.$emit('change', index + 1);
       }
+    },
+
+    onTouchMove(event) {
+      if (!document.elementFromPoint) {
+        return;
+      }
+
+      event.preventDefault();
+      const { clientX, clientY } = event.touches[0];
+      const target = document.elementFromPoint(clientX, clientY);
+      if (target && target.dataset) {
+        const { index } = target.dataset;
+
+        /* istanbul ignore else */
+        if (index) {
+          this.onSelect(+index);
+        }
+      }
     }
   }
 });