Hardware backbutton doesn't close app

[dankawka]

I'm submitting a ... (check one with "x")
[X] bug report
[ ] feature request
[ ] support request => Please do not submit support requests here, use one of these channels: https://forum.ionicframework.com/ or http://ionicworldwide.herokuapp.com/

Current behavior:
When I tap hardware back button on my Galaxy S8 application does not close when there are no more "possibilities" to go back.

Expected behavior:
After going back through all pages and being on the last, hardware button should close the app.

Steps to reproduce:

1. Run app on device
2. Click any event
3. Event details page opens
4. Tap hardware back button
5. We are back at list of events
6. Tap hardware back button
7. Nothing happens <- at this point application should close.

[kangjichang2009]

how to exitApp? ionic3 this platForm.exitApp() has No effect!

[dankawka]

Switch to Flutter.

[kangjichang2009]

ionic4 how to exitApp?

[WouterWidgets]

I'm using this:

In app.component.ts (e.g. inside initializeApp() method)

this.platform.backButton.subscribeWithPriority(0, () => {
  if (!document.querySelector('.ion-page.can-go-back:not(.ion-page-hidden)')) {
    (navigator as any).app.exitApp();
  }
});