Enable ionViewWillEnter in tabs ionic, https://github.com/ionic-team/ionic/issues/16834

payment.js

import { Component, OnInit, OnDestroy, ViewChild } from '@angular/core';
import { IonTabs } from '@ionic/angular';
import { Subscription } from 'rxjs';

export interface Tab {
  tabsWillEnter();
  tabsDidEnter();
  tabsWillLeave();
  tabsDidLeave();
}
@Component({
  selector: 'app-payment',
  templateUrl: './payment.page.html',
  styleUrls: ['./payment.page.scss'],
})

export class PaymentPage implements OnInit, OnDestroy {
  @ViewChild('tabs', { static: true }) tabs: IonTabs;
  private subs = new Subscription();
  private currentTab: Tab;
  private tabsDidEnter = false;
  constructor() { }

  ngOnInit() {
    const tabSub = this.tabs.ionTabsDidChange.subscribe(() => {
      this.currentTab = this.tabs.outlet.component as Tab;
    });
    this.subs.add(tabSub);
  }

  ionViewWillEnter() {
    if (this.tabsDidEnter) { // Do not fire on initial load - ionViewWillEnter of child tab will fire
      this.currentTab.tabsWillEnter(); 
    }
  }

  ionViewDidEnter() {
    if (this.tabsDidEnter) { // Do not fire on initial load - ionViewDidEnter of child tab will fire
      this.currentTab.tabsDidEnter(); 
    }
    this.tabsDidEnter = true;
  }

  ionViewWillLeave() {
    this.currentTab.tabsWillLeave();
  }

  ionViewDidLeave() {
    this.currentTab.tabsDidLeave();
  }

  ngOnDestroy() {
    this.subs.unsubscribe();
  }

}