Unable to get the sidemenu in ionic2

Ionic Framework ionic-v3
1 
Hello, I get the error as 'Cannot read property 'enable' of undefined'

My sidemenu.ts code:

import {Page,NavController,NavParams,IonicApp,MenuController} from 'ionic-angular';
@Page({
    templateUrl: 'build/pages/sidemenu/sidemenu.html'
})
export class SideMenu {
private nav,app,menu;

constructor(public platform: Platform, nav : NavController,public navParams: NavParams,app: IonicApp,menu: MenuController){

this.app = app;

        this.menu = menu;

    app.getComponent('leftMenu').enable(true);
}
}


My sidemenu.html code:

<ion-navbar *navbar hideBackButton>
    <button menuToggle="leftMenu">
        <ion-icon name='menu'></ion-icon>
    </button>
 <ion-title>Select an App</ion-title>
</ion-navbar>

What could be the issue for this? Please Help.
2

I think you must do : this.menu.open();