ionic-framework/core/src/components/toast-controller/toast-controller.tsx

import { Component, Method, Prop } from '@stencil/core';

import { OverlayController, ToastOptions } from '../../interface';
import { createOverlay, dismissOverlay, getOverlay } from '../../utils/overlays';

@Component({
  tag: 'ion-toast-controller'
})
export class ToastController implements OverlayController {

  @Prop({ context: 'document' }) doc!: Document;

  /**
   * Create a toast overlay with toast options.
   */
  @Method()
  create(opts?: ToastOptions): Promise<HTMLIonToastElement> {
    return createOverlay(this.doc.createElement('ion-toast'), opts);
  }

  /**
   * Dismiss the open toast overlay.
   */
  @Method()
  dismiss(data?: any, role?: string, toastId?: number) {
    return dismissOverlay(this.doc, data, role, 'ion-toast', toastId);
  }

  /**
   * Get the most recently opened toast overlay.
   */
  @Method()
  getTop(): HTMLIonToastElement {
    return getOverlay(this.doc, 'ion-toast') as HTMLIonToastElement;
  }
}