可以先贴个代码，字面意思来讲是canvas画布没找到。
phpget_footer();?> And I'm trying to access it in a JS file: varcanvas=document.getElementById('menu_class');varctx=canvas.getContext('2d'); But when I run my program, I get this error: Uncaught TypeError: Cannot read property 'getContext' of nullat app.js?ver=4.8.1:2 So, I...
[Vue warn]: Error in mounted hook: "TypeError: Cannot read property 'getContext' of null" found in ---> <Index> at src/pages/index/index.vue <Anonymous> <Anonymous> <Root> TypeError: Cannot read property 'getContext' of null at createCanvasContext (createCanvasContext.js?306b:13) at...
Link.js:11UncaughtTypeError:Cannotread property'context'ofnullat handleClick (http://localhost:3000/static/js/bundle.js:33792:12)atObject.ReactErrorUtils.invokeGuardedCallback(http://localhost:3000/static/js/bundle.js:17162:17)at executeDispatch (http://localhost:3000/static/js/bundle.js:16945:22...
Cannot read property "getContext" of undefined It only happen after i package the app, not in dev mode, where everything works as expected. here my code from the window import{ ipcRenderer }from"electron";letcanvasEl, stage, queue; ipcRenderer.on("render-spritesheets",(_, data) =>{co...
Steps to reproduce Uncaught (in promise) TypeError: Cannot read property 'appContext' of null 1.0.2-beta.54 版本报这个错 What is Expected? 不报错 What is actually happening? 不报错 Translation of this issue: Element Plus version 1.0.2-beta.54 ...
uniapp 根组建内 获取webview 使用代码 // #ifdef APP-PLUS var currentWebview = this.$scope.$getAppWebview() //此对象相当于html5plus里的plus.webview.currentWebview()。在uni-app里vue页面直接使用plus.webview.currentWebview()无效,非v3编译模式使用this.$mp.page.$getAppWebview() ...
I get this Build error when using appdir experimental / swcNo error when not using appdir experimental TypeError: Cannot read properties of null (reading 'useContext') -- 21:43:44.798 | at exports.useContext (/vercel/path0/node_modules/react/cjs/react.production.min.js:24:118) 21:4...
TypeError: Cannot read property '$options' of undefined 先渲染,后获值。建议使用async函数做个串联顺序控制。 添加“runValidators:true”后,我的Mongoose update函数出错,“cannot read property”ownerDocument为null` 如果使用mongoose-unique-validator插件和findOneAndUpdate和相关方法,则需要将context选项设置为'query...
typeError: cannot read property 'appId' of undefine - 预期表现 什么叫预期表现 - 复现路径 什么路径 - 提供一个最简复现 Demo 什么demo 就提个问题 这么多事儿 代码片段 // page/editcard/editcard.js var app = getApp() Page({ /** * 页面的初始数据 */ data: { userName: "司马相如"...