[4.0.0-rc.0] Android back button can unexpectedly switch tabs

[qiluo]

Bug Report

Ionic version:

[x] 4.x

Current behavior:

When you tap on Android back button, it can unexpectedly switch tabs

Expected behavior:

On the tabs layout, Android back button should do nothing, since tabs layout is root component already

Steps to reproduce:

1. create a new project from tabs starter
2. add platform android
3. run app on Android device
4. randomly tap on any tab to generate a navigation history
5. keep tapping on Android back button, the app just went way back of all its navigation history

Related code:

insert short code snippets here

Other information:

Ionic info:

Ionic:

   ionic (Ionic CLI)             : 4.6.0 (/usr/local/lib/node_modules/ionic)
   Ionic Framework               : @ionic/angular 4.0.0-rc.0
   @angular-devkit/build-angular : 0.11.4
   @angular-devkit/schematics    : 7.1.4
   @angular/cli                  : 7.1.4
   @ionic/angular-toolkit        : 1.2.2

Cordova:

   cordova (Cordova CLI) : 8.1.2 (cordova-lib@8.1.1)
   Cordova Platforms     : android 7.1.4
   Cordova Plugins       : cordova-plugin-ionic-keyboard 2.1.3, cordova-plugin-ionic-webview 2.3.1, (and 4 other plugins)

System:

   Android SDK Tools : 26.1.1 (/Users/Dev/Android/android-sdk-macosx)
   ios-deploy        : 1.9.4
   ios-sim           : 6.1.2
   NodeJS            : v10.14.2 (/usr/local/bin/node)
   npm               : 6.4.1
   OS                : macOS Sierra
   Xcode             : Xcode 9.2 Build version 9C40b

[amitairos]

I would suggest differentiating between top tabs to bottom tabs. Top tabs should not respond to back button, while bottom tabs should maybe navigate to the home button.

[qiluo]

I would suggest differentiating between top tabs to bottom tabs. Top tabs should not respond to back button, while bottom tabs should maybe navigate to the home button.

In my case, it's bottom tabs. But if you look at native apps, they don't really switch either top or bottom tabs by Android back button in most cases

[paulstelzer]

This is something for #16611

[ionitron-bot]

Thanks for the issue! This issue is being closed due to inactivity. If this is still an issue with the latest version of Ionic, please create a new issue and ensure the template is fully filled out.

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