当我尝试在angular 2应用程序中使用angular2-material时，什么都不渲染

Question

这是我的app.module.ts代码。我正在尝试创建一个消息传递应用程序，但它不运行任何角度材料模块

import { NgModule }      from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { MaterialModule } from '@angular/material';
import { AppComponent }  from './app.component';
import { MessagesComponent} from './messages-component';


@NgModule({
  imports:      [ BrowserModule,MaterialModule],
  declarations: [ AppComponent, MessagesComponent ],
  bootstrap:    [ AppComponent ]
})
export class AppModule { }

下面是我的message-components.ts文件

import { Component } from '@angular/core';
//this is a component a basic building block of angular this ,components run like trees

@Component({
    selector : 'messages',
    template : `

    <div *ngFor="let message of messages">

        <md-card>{{message.owner}}<md-card>
        {{message.text}} 

    </div>
    `

})
export class MessagesComponent {

    messages =[{text:'some text',owner:'Bruce'}, {text:'hello',owner:'Caleb'}];
}
//the template for the component, every component must have a template

她的是我的system.js文件

'@angular/material': 'npm:@angular/material/bundles/material.umd.js'
    },

这是我的错误消息0 info如果它以ok 1 verbose cli [ 'C:\Program Files\nodejs\node.exe'，1 verbose cli结束

'C:\\Users\\bruce\\AppData\\Roaming\\npm\\node_modules\\npm\\bin\\npm-cli.js',
1 verbose cli   'start' ]
2 info using npm@5.3.0
3 info using node@v8.2.1
4 verbose run-script [ 'prestart', 'start', 'poststart' ]
5 info lifecycle angular-quickstart@1.0.0~prestart: angular-quickstart@1.0.0
6 verbose lifecycle angular-quickstart@1.0.0~prestart: unsafe-perm in lifecycle true
7 verbose lifecycle angular-quickstart@1.0.0~prestart: PATH: C:\Users\bruce\AppData\Roaming\npm\node_modules\npm\bin\node-gyp-bin;C:\Users\bruce\Desktop\dev\messageboard\frontend\node_modules\.bin;C:\Program Files\Microsoft MPI\Bin\;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\Program Files\Microsoft SQL Server\130\Tools\Binn\;C:\Program Files\dotnet\;C:\Program Files\Anaconda3;C:\Program Files\Anaconda3\Scripts;C:\Program Files\Anaconda3\Library\bin;C:\Program Files\Git\cmd;C:\Program Files (x86)\GtkSharp\2.12\bin;C:\Program Files\nodejs\;C:\Users\bruce\AppData\Local\Microsoft\WindowsApps;C:\Program Files (x86)\Microsoft VS Code\bin;C:\Users\bruce\AppData\Roaming\npm
8 verbose lifecycle angular-quickstart@1.0.0~prestart: CWD: C:\Users\bruce\Desktop\dev\messageboard\frontend
9 silly lifecycle angular-quickstart@1.0.0~prestart: Args: [ '/d /s /c', 'npm run build' ]
10 silly lifecycle angular-quickstart@1.0.0~prestart: Returned: code: 2  signal: null
11 info lifecycle angular-quickstart@1.0.0~prestart: Failed to exec prestart script
12 verbose stack Error: angular-quickstart@1.0.0 prestart: `npm run build`
12 verbose stack Exit status 2
12 verbose stack     at EventEmitter.<anonymous> (C:\Users\bruce\AppData\Roaming\npm\node_modules\npm\lib\utils\lifecycle.js:289:16)
12 verbose stack     at emitTwo (events.js:125:13)
12 verbose stack     at EventEmitter.emit (events.js:213:7)
12 verbose stack     at ChildProcess.<anonymous> (C:\Users\bruce\AppData\Roaming\npm\node_modules\npm\lib\utils\spawn.js:40:14)
12 verbose stack     at emitTwo (events.js:125:13)
12 verbose stack     at ChildProcess.emit (events.js:213:7)
12 verbose stack     at maybeClose (internal/child_process.js:921:16)
12 verbose stack     at Process.ChildProcess._handle.onexit (internal/child_process.js:211:5)
13 verbose pkgid angular-quickstart@1.0.0
14 verbose cwd C:\Users\bruce\Desktop\dev\messageboard\frontend
15 verbose Windows_NT 10.0.15063
16 verbose argv "C:\\Program Files\\nodejs\\node.exe" "C:\\Users\\bruce\\AppData\\Roaming\\npm\\node_modules\\npm\\bin\\npm-cli.js" "start"
17 verbose node v8.2.1
18 verbose npm  v5.3.0
19 error code ELIFECYCLE
20 error errno 2
21 error angular-quickstart@1.0.0 prestart: `npm run build`
21 error Exit status 2
22 error Failed at the angular-quickstart@1.0.0 prestart script.
22 error This is probably not a problem with npm. There is likely additional logging output above.
23 verbose exit [ 2, true ]

这是我的index.html文件

<!DOCTYPE html>
<html>
  <head>
    <title>Angular QuickStart</title>
    <base href="/">
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel="stylesheet" href="styles.css">
   <link href="node_modules/@angular/material/prebuilt-themes/indigo-pink.css" rel="stylesheet">

    <!-- Polyfill(s) for older browsers -->
    <script src="node_modules/core-js/client/shim.min.js"></script>

    <script src="node_modules/zone.js/dist/zone.js"></script>
    <script src="node_modules/systemjs/dist/system.src.js"></script>

    <script src="systemjs.config.js"></script>
    <script>
      System.import('main.js').catch(function(err){ console.error(err); });
    </script>
  </head>

  <body>
    <my-app>Loading AppComponent content here ...</my-app>
  </body>
</html>

Answer 1

最新的angular2和angular2-material已经改变了他们设置系统的方式

您可以尝试执行以下步骤-

• 添加到您的systemjs.config.js作为：

map: {
  // our app is within the app folder
  app: 'app',
    :
    '@angular/material': 'npm:@angular/material/material.umd.js',
    :
}

更改您的app.module.ts:的

from

@NgModule({
      imports:      [ BrowserModule, MaterialModule],
to

 @NgModule({
      imports:      [ BrowserModule, MaterialModule.forRoot()],