chore: use the function replace expression

src/index.vue

@@ -527,7 +527,7 @@ export default {
     },
     handleFocus (event) {
       if (!this.popupVisible) {
-        this.popupVisible = true
+        this.showPopup()
       }
       this.$emit('focus', event)
     },
@@ -536,10 +536,10 @@ export default {
       // Tab 9 or Enter 13
       if (keyCode === 9 || keyCode === 13) {
         // ie emit the watch before the change event
+        event.stopPropagation()
         this.handleChange()
         this.userInput = null
-        this.popupVisible = false
-        event.stopPropagation()
+        this.closePopup()
       }
     },
     handleInput (event) {