问云开发教程里的教程，我按照步骤做怎么就出错？

云开发教程里的教程，我按照步骤做怎么就出错，添加图书这一课

VM11511:1 appServiceSDKScriptErro

Cannot read property 'mode' of undefined;at api onAppEnterBackground callback function

TypeError: Cannot read property 'mode' of undefined

at Bt.<anonymous> (http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:525987)

at Bt.emit (http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:305615)

at Object.emit (http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:324480)

at Bt.<anonymous> (http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:330528)

at Bt.emit (http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:305657)

at Object.emit (http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:324480)

at http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:325658

at http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:262652

at e (http://127.0.0.1:22791/appservice/appservice?t=1547345599650:3690:2640)

at n.registerCallback.t (http://127.0.0.1:22791/appservice/appservice?t=1547345599650:3690:2903)

console.error @ VM11511:1

errorReport @ WAService.js:1

(anonymous) @ WAService.js:1

(anonymous) @ WAService.js:1

e @ appservice?t=1547345599650:3690

n.registerCallback.t @ appservice?t=1547345599650:3690

l.forEach.t @ appservice?t=1547345599650:3690

(anonymous) @ appservice?t=1547345599650:3690

s.onmessage @ appservice?t=1547345599650:3690

VM11511:1 thirdScriptErro

console.errot is not a function;at api cloud.callFunction fail callback function

TypeError: console.errot is not a function

at Function.fail (http://127.0.0.1:22791/appservice/pages/scancode/scancode.js:70:21)

at Function.<anonymous> (http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:101864)

at http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:196767

at i (http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:196476)

at http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:196745

at i (http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:132207)

at Object.t.invokeFailCompleteCallbacks (http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:132534)

at http://127.0.0.1:22791/appservice/__dev__/WAService.js:1:175728

at <anonymous>