[improvement] Checkbox: use relation mixin

packages/mixins/checkbox.js

@@ -2,10 +2,10 @@
  * Common part of Checkbox & Radio
  */
 import Icon from '../icon';
-import { FindParentMixin } from './find-parent';
+import { ChildrenMixin } from './relation';
 
 export const CheckboxMixin = (parent, bem) => ({
-  mixins: [FindParentMixin],
+  mixins: [ChildrenMixin(parent)],
 
   props: {
     name: null,
@@ -20,10 +20,6 @@ export const CheckboxMixin = (parent, bem) => ({
     }
   },
 
-  created() {
-    this.findParent(parent);
-  },
-
   computed: {
     isDisabled() {
       return (this.parent && this.parent.disabled) || this.disabled;

packages/mixins/find-parent.js

@@ -1,24 +0,0 @@
-/**
- * find parent component by name
- */
-
-export const FindParentMixin = {
-  data() {
-    return {
-      parent: null
-    };
-  },
-
-  methods: {
-    findParent(name) {
-      let parent = this.$parent;
-      while (parent) {
-        if (parent.$options.name === name) {
-          this.parent = parent;
-          break;
-        }
-        parent = parent.$parent;
-      }
-    }
-  }
-};

packages/mixins/relation.js

@@ -1,6 +1,10 @@
 export function ChildrenMixin(parent) {
   return {
-    inject: [parent],
+    inject: {
+      [parent]: {
+        default: null
+      }
+    },
 
     computed: {
       parent() {
@@ -18,11 +22,17 @@ export function ChildrenMixin(parent) {
     },
 
     beforeDestroy() {
-      this.parent.children = this.parent.children.filter(item => item !== this);
+      if (this.parent) {
+        this.parent.children = this.parent.children.filter(item => item !== this);
+      }
     },
 
     methods: {
       bindRelation() {
+        if (!this.parent) {
+          return;
+        }
+
         const { children } = this.parent;
 
         if (children.indexOf(this) === -1) {