Uncaught TypeError: Cannot read properties of undefined (reading ‘meta‘)

项目场景：

记录第一次编写uniapp遇到的报错
注意，我写的是app。

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问题描述

新建项目，抄了一个组件，HBuilder X选择运行到浏览器，F12发现报错

• 报错信息如下

Uncaught TypeError: Cannot read properties of undefined (reading 'meta')
    at uni-h5.es.js:19551:24
    at callWithErrorHandling (vue.runtime.esm.js:1309:22)
    at callWithAsyncErrorHandling (vue.runtime.esm.js:1318:21)
    at ReactiveEffect.getter [as fn] (vue.runtime.esm.js:2938:24)
    at ReactiveEffect.run (vue.runtime.esm.js:187:25)
    at doWatch (vue.runtime.esm.js:3046:16)
    at watchEffect (vue.runtime.esm.js:2858:12)
    at useSwitchTab (uni-h5.es.js:19550:3)
    at setup (uni-h5.es.js:19497:25)
    at callWithErrorHandling (vue.runtime.esm.js:1309:22)

• 报出的警示信息如下

App.vue:4 当前组件仅支持 uni_modules 目录结构 ，请升级 HBuilderX 到 3.1.0 版本以上！
onLaunch @ App.vue:4
App.vue:5 App Launch
App.vue:8 App Show
uni-h5.es.js:14220 [Vue warn]: injection "Symbol([vue-router]: route location)" not found. 
 at <TabBar>
at <Layout>
at <App>
warnHandler @ uni-h5.es.js:14220
uni-h5.es.js:14220 [Vue warn]: Unhandled error during execution of watcher callback 
 at <TabBar>
at <Layout>
at <App>
warnHandler @ uni-h5.es.js:14220
uni-h5.es.js:14220 [Vue warn]: Unhandled error during execution of setup function 
 at <TabBar>
at <Layout>
at <App>
warnHandler @ uni-h5.es.js:14220

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原因分析：

报错信息如图：

原因很明显，route不能是undefined，报错位置发生在自定义的tabbar中；
那么是谁调用了useSwitchTab这个方法呢我们找一下。

我稍微往上找了以下，发现是这里调用的

这里是我在pages.json中的tabbar配置的数据
很明显，这三个文件我还没创建，所以我报错了。嗯嗯，骂早了不好意思我道歉。

默默地把这几个文件补上，然后重启。

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值得一提的是
警示类型的这段代码是app.vue写不想看就删掉。

App.vue:4 当前组件仅支持 uni_modules 目录结构 ，请升级 HBuilderX 到 3.1.0 版本以上！

路径方面看看官网给的示例：

这个示例给你之后，你能用个der，少给你写了点东西

你的像下面这么写

{
	"pages": [
		{
			"path": "pages/home/index",
			"style": {
				"navigationBarTitleText": "主页",
				"enablePullDownRefresh": true
				// "navigationStyle": "custom"
			}
		}, {
			"path": "pages/my/index",
			"style": {
				"navigationBarTitleText": "我的",
				"enablePullDownRefresh": true
				// "navigationStyle": "custom"
			}
		}
	],
	"globalStyle": {
		"navigationBarTextStyle": "black",
		"navigationBarTitleText": "uni-app",
		"navigationBarBackgroundColor": "#F8F8F8",
		"backgroundColor": "#F8F8F8",
		"app-plus": {
			"background": "#efeff4"
		}
	},
	"tabBar": {
		"color": "#7A7E83",
		"selectedColor": "#3cc51f",
		"borderStyle": "black",
		"backgroundColor": "#ffffff",
		"list": [{
			"pagePath": "pages/home/index",
			"iconPath": "static/img/tabber/c1.png",
			"selectedIconPath": "static/img/tabber/c2.png",
			"text": "主页"
		}, {
			"pagePath": "pages/my/index",
			"iconPath": "static/img/tabber/c3.png",
			"selectedIconPath": "static/img/tabber/c4.png",
			"text": "我的"
		}]
	}
}

效果