docs(uni-app x): plugins and globalData

docs/uni-app-x/tutorial/codegap.md

@@ -269,6 +269,50 @@ request({url: 'https://www.example.com/request'} as RequestOptions)
 
 ![](../static/go-to-definition.png)
 
+## 插件
+
+- uni-app x 暂不支持 i18n、Vuex、Pinia 等插件。
+
+## 全局变量
+
+可通过一个专用模块组织和管理全局变量，例如：
+
+```ts
+// store/index.uts
+export type State = {
+  globalNum: number
+}
+
+export const state = reactive({ globalNum: 0 } as State)
+
+export const setGlobalNum = (num: number) => {
+  state.globalNum = num
+}
+```
+
+```ts
+// pages/index/index.uvue
+<template>
+	<text @click="plus">{{ globalNum }}</text>
+</template>
+
+<script>
+	import { state, setGlobalNum } from '@/store/index.uts'
+	export default {
+		computed: {
+			globalNum(): number {
+				return state.globalNum
+			}
+		},
+		methods: {
+			plus(){
+				setGlobalNum(state.globalNum + 1)
+			}
+		}
+	}
+</script>
+```
+
 ## uts不支持js的一些功能和特性
 
 - 不支持undefined。任何变量被定义后，都需要赋值