refactor(radio): handleMouseDown focus logic

CHANGELOG.en-US.md

@@ -1,7 +1,7 @@
 # CHANGELOG
 ## PENDING
 ### Refactors
-- Refactor `n-tag` styles
+- Refactor `n-tag` styles.
 - Fix the problem that `n-data-table`'s `max-height` style is broken. https://bugs.chromium.org/p/chromium/issues/detail?id=1107223
 
 ## 1.5.1 (2020-07-20)

CHANGELOG.zh-CN.md

@@ -6,7 +6,7 @@
 
 ## 1.5.1 (2020-07-20)
 ### Features
-- 为 `n-time-picker`　增加了　`disabled`　属性.
+- 为 `n-time-picker`　增加了　`disabled`　属性
 ### Fixes
 - 修正了 `n-radio`下的子元素无法获取焦点的问题
 

src/Radio/src/radioMixin.js

@@ -75,10 +75,13 @@ export default {
     handleKeyUpEnter () {
       this.toggle()
     },
-    handleMouseDown (e) {
+    handleMouseDown () {
       if (this.syntheticDisabled) return
-      // e.preventDefault()
-      this.$refs.input.focus()
+      setTimeout(() => {
+        if (!this.$el.contains(document.activeElement)) {
+          this.$refs.input.focus()
+        }
+      }, 0)
     },
     handleClick (e) {
       this.$emit('click', e)