Ionic 2 customize back button action

Question

I want to customize the click-action of the back button mentioned in this screen capture. I want that by clicking I do not return to the previous page but to a page that I specify myself, or do a treatment before going back.

Answer 1

For customize default back button action you need override the backButtonClick() method of the NavBar component.

Step 1: In your "custom-class.ts" import Navbar component. Create auxMethod for override the default behavior and called in your ionViewDidLoad method.

import { Navbar } from 'ionic-angular';
import { ViewChild } from '@angular/core';

export class myCustomClass {
    @ViewChild(Navbar) navBar: Navbar;

    ionViewDidLoad() {
        this.setBackButtonAction()
    }

    //Method to override the default back button action
    setBackButtonAction(){
       this.navBar.backButtonClick = () => {
       //Write here wherever you wanna do
          this.navCtrl.pop()
       }
    }
}

This code has been tested in ionic 3.

Answer 2

You can try to use ionViewCanLeave or ionViewWillLeave event.

See this issue #9533 with proposal to distinguish leave events for "back" navigation. This can be handy for your use case once implemented.