[IONIC 4] Get current tab index

Hey guys,

I’m working on an app created with Ionic Tabs, and I’m wondering how to get a tab index when I change from a tab to another.
I’ve found how to do it with Ionic 2 and 3, but this doesn’t work anymore with Ionic 4.

I need it in order to show a nice page transition between my tabs when the user navigates from one to another.

If you need some code, feel free to ask, but I don’t know what to show here ^^

If you have any ideas…
Thanks !