Angular Material无法正常使用颜色和动画

Question

嗨，伙计们，我正在关注MEAN堆栈的Max的Udemy教程，我遇到了Material问题，现在元素没有显示出来。

材料和* ngFor曾经在我使计算机进入睡眠状态之前工作。 我的设置：Ubuntu，VSCode，节点：10.15.3，npm：6.7.0

这是我的repo

angular-cli也向我显示此警告：

  

您的全局Angular CLI版本（7.3.6）大于本地版本   版本（7.0.7）。使用本地Angular CLI版本。

<mat-accordion>
  <mat-expansion-panel *ngFor="let post of posts">
    <mat-expansion-panel-header>
      {{post.title}}
    </mat-expansion-panel-header>
    <p>{{post.content}}</p>
  </mat-expansion-panel>
</mat-accordion>

package.json

{
  "name": "mean-course",
  "version": "0.0.0",
  "scripts": {
    "ng": "ng",
    "start": "ng serve",
    "build": "ng build",
    "test": "ng test",
    "lint": "ng lint",
    "e2e": "ng e2e"
  },
  "private": true,
  "dependencies": {
    "@angular/animations": "~7.0.0",
    "@angular/cdk": "~7.3.5",
    "@angular/common": "~7.0.0",
    "@angular/compiler": "~7.0.0",
    "@angular/core": "~7.0.0",
    "@angular/forms": "~7.0.0",
    "@angular/http": "~7.0.0",
    "@angular/material": "^7.3.5",
    "@angular/platform-browser": "~7.0.0",
    "@angular/platform-browser-dynamic": "~7.0.0",
    "@angular/router": "~7.0.0",
    "core-js": "^2.5.4",
    "rxjs": "~6.3.3",
    "zone.js": "~0.8.26"
  },
  "devDependencies": {
    "@angular-devkit/build-angular": "~0.10.0",
    "@angular/cli": "~7.0.3",
    "@angular/compiler-cli": "~7.0.0",
    "@angular/language-service": "~7.0.0",
    "@types/node": "~8.9.4",
    "@types/jasmine": "~2.8.8",
    "@types/jasminewd2": "~2.0.3",
    "codelyzer": "~4.5.0",
    "jasmine-core": "~2.99.1",
    "jasmine-spec-reporter": "~4.2.1",
    "karma": "~3.0.0",
    "karma-chrome-launcher": "~2.2.0",
    "karma-coverage-istanbul-reporter": "~2.0.1",
    "karma-jasmine": "~1.1.2",
    "karma-jasmine-html-reporter": "^0.2.2",
    "protractor": "~5.4.0",
    "ts-node": "~7.0.0",
    "tslint": "~5.11.0",
    "typescript": "~3.1.1"
  }
}

Answer 1

将post-list.component.html的第n°9行更改为

<p class="info-text mat-body-1" ngIf="posts.length <= 0"> No posts yet!</p>

到

<p class="info-text mat-body-1" *ngIf="posts.length <= 0"> No posts yet!</p>

您错过了*中的*ngIf。

---

为警告起见，它只是说您在全局（npm install -g）上安装的@ angular / cli比您的package.json中的一个更大，但这不是问题的根源。