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

Code Example 1

import { Component } from '@angular/core';
import { PopoverController } from '@ionic/angular';
import { PopoverComponent } from '../../component/popover/popover.component';

@Component({
  selector: 'popover-example',
  templateUrl: 'popover-example.html',
  styleUrls: ['./popover-example.css']
})
export class PopoverExample {
  constructor(public popoverController: PopoverController) {}

  async presentPopover(ev: any) {
    const popover = await this.popoverController.create({
      component: PopoverComponent,
      event: ev,
      translucent: true
    });
    return await popover.present();
  }
}

Learn ReactJs, React Native from akashmittal.com