'mat-toolbar' is not a known element - Angular 5

Question

I have created a new project, and I am trying to add angular-material.

I have created material.module.ts in my app folder:

Answer 1

That's because you have to import a module to the module which contains the component declaration, not into the component itself:

app.module.ts

import { MaterialModule } from './material.module';

@NgModule({
  imports: [
    // ...
    MaterialModule
  ],
  declarations: [
    MyCoolComponent,
    // ...
  ]
})

P.S. The correct way to use a material icon is to use the MatIcon component. Example usage:

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