Properly plugins usage

Hello!

Currently i'm creating a simple app.
And want to use some plugins, such as Google Maps.
I've read https://market.ionic.io/starters/google-maps starter and have some questions about using plugins with ionic.
Here the my controller

.controller('PlaylistsCtrl', function($scope, $ionicPlatform) {
    $ionicPlatform.ready(function() {
        var div = document.getElementById("map_canvas");
        console.log(JSON.stringify(div));

        // Invoking Map using Google Map SDK v2 by dubcanada
        var map = plugin.google.maps.Map.getMap(div,{
        'camera': {
            'latLng': setPosition(-19.9178713, -43.9603117),
            'zoom': 10
        }
        });


        // Capturing event when Map load are ready.
        map.addEventListener(plugin.google.maps.event.MAP_READY, function(){

        // Defining markers for demo
        var markers = [{
            position: setPosition(-19.9178713, -43.9603117),
            title: "Marker 1"
        }, {
            position: setPosition(-19.8363826, -43.9787167),
            title: "Marker 2"
        }];

        // Bind markers
        for (var i = 0; i < markers.length; i++) {
            map.addMarker({
            'marker': markers[i],
            'position': markers[i].position
            }, function(marker) {

            // Defining event for each marker
            marker.on("click", function() {
                alert(marker.get('marker').title);
            });

            });
        }
        });


        // Function that return a LatLng Object to Map
        function setPosition(lat, lng) {
        return new plugin.google.maps.LatLng(lat, lng);
        }
    });

    $scope.playlists = [
        { title: 'Reggae', id: 1 },
        { title: 'Chill', id: 2 },
        { title: 'Dubstep', id: 3 },
        { title: 'Indie', id: 4 },
        { title: 'Rap', id: 5 },
        { title: 'Cowbell', id: 6 }
    ];
    })

In template i have div with id map_canvas.
Plugin are installed and keys passed with installation.
Running on device with live reload.
But console.log(JSON.stringify(div)); empty

How properly use plugin in this case?

Thanks!