tab2.page.html

    1. <ion-content>
    2.   <ion-button color="primary" (click)="presentAlert()">Primary</ion-button>
    3. </ion-content>

    tab2.page.ts

    1. export class Tab2Page {
    2.   constructor(public alertController: AlertController) {}
    3.   async presentAlert() {
    4.     const alert = await this.alertController.create({
    5.       header: 'Alert',
    6.       subHeader: 'Subtitle',
    7.       message: 'This is an alert message.',
    8.       buttons: ['OK']
    9.     });
    10.     await alert.present();
    11.   }
    12. }