问题在代码中使用Angular Material提供的CDK Overlay模块。

代码示例：

首先，引入Overlay模块：

import { OverlayModule } from '@angular/cdk/overlay';

然后，创建一个主题工厂：

import { ThemePalette } from '@angular/material/core'; import { MatButton } from '@angular/material/button';

@Injectable() export class MyButtonThemeFactory { constructor(private _palette: ThemePalette) {}

createButtonWithTheme(): typeof MatButton { const MyButtonWithTheme = class extends MatButton { constructor(...args: any[]) { super(...args); this.color = this._palette; } };

return MyButtonWithTheme;

} }

然后，在组件中使用CDK Overlay模块创建一个新的按钮：

import { Overlay } from '@angular/cdk/overlay';

@Component({ template: Open Overlay , }) export class MyComponent { @ViewChild('buttonRef') buttonRef: MatButton;

constructor( private _overlay: Overlay, private _buttonThemeFactory: MyButtonThemeFactory, ) {}

ngAfterViewInit() { const MyButtonWithTheme = this._buttonThemeFactory.createButtonWithTheme();

const positionStrategy = this._overlay
  .position()
  .flexibleConnectedTo(this.buttonRef._elementRef)
  .withPositions([
    {
      originX: 'center',
      originY: 'bottom',
      overlayX: 'center',
      overlayY: 'top',
    },
  ]);

const overlayRef = this._overlay.create({
  positionStrategy,
  scrollStrategy: this._overlay.scrollStrategies.reposition(),
  hasBackdrop: true,
  backdropClass: 'cdk-overlay-transparent-backdrop',
  panelClass: 'my-panel',
});

overlayRef
  .backdropClick()
  .subscribe(() => overlayRef.detach());

const buttonPortal = new ComponentPortal(MyButtonWithTheme);

const buttonRef = overlayRef.attach(buttonPortal);

} }

这样就可以在Angular Material v15里更新工程中遗留的按钮样式，保证所设置的主题可以应用于所有按钮。