Check out example codes for "ionic toast". It will help you in understanding the concepts better.

Code Example 1

constructor(public toastController: ToastController) {}

async presentToast() {
  const toast = await this.toastController.create({
    message: 'Your settings have been saved.',
    duration: 2000
  });
  toast.present();
}

Code Example 2

import { Component } from '@angular/core';
import { ToastController } from '@ionic/angular';

@Component({
  selector: 'toast-example',
  templateUrl: 'toast-example.html',
  styleUrls: ['./toast-example.css'],
})
export class ToastExample {

  constructor(public toastController: ToastController) {}

  async presentToast() {
    const toast = await this.toastController.create({
      message: 'Your settings have been saved.',
      duration: 2000
    });
    toast.present();
  }

  async presentToastWithOptions() {
    const toast = await this.toastController.create({
      header: 'Toast header',
      message: 'Click to Close',
      position: 'top',
      buttons: [
        {
          side: 'start',
          icon: 'star',
          text: 'Favorite',
          handler: () => {
            console.log('Favorite clicked');
          }
        }, {
          text: 'Done',
          role: 'cancel',
          handler: () => {
            console.log('Cancel clicked');
          }
        }
      ]
    });
    toast.present();
  }

}

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