Event "backKeyDown" doesnt work

1

Hello!
I need to call an event to going back on mobile.
i just add "backKeydown to events in app (app.js)
but it does not react. Any ideas?

var app = new Framework7({
...,
 view: {
        pushState: true
    },
	 pushState: true,
...
     on: {
        init: function () {
          var f7 = this;
          if (f7.device.cordova) {
            // Init cordova APIs (see cordova-app.js)
            cordovaApp.init(f7);
          }
        },
    	 backKeyDown: function() {
    		alert('1')
               if (app.views.main.router.url == '/') {

                        navigator.app.exitApp();
                } else {
    			mainView.router.navigate('/', {});
                
               }

    }
      },
  
});
2

“backKeyDown” isn’t a Framework7 event.
“backKeyDown” (backbutton actually) is a Cordova event, if you looked inside cordova-app.js you will see the subscription to the backbutton event.