How to call a function within an addeventlistener?

Question

I wonder if it is possible to call a function within a given event using addeventlistener().

I have this function, which adds a reward to the database :

    //Função que adiciona uma recompensa ao banco de dados
addReward(){
    if(!this.isEditing){
    this.addDocument(this.caminho, this.recompensa).then(()=>{
      //this.loadData();//refresh view
    });
  }else{
    this.updateDocument(this.caminho, this.recompensa.key, 
    this.recompensa).then(()=>{
      this.loadData();//refresh view
    });
  }
  this.isEditing = false;
  //clear form
  this.recompensa.valor;
  this.recompensa.data;
}

here I have the function that displays a particular ad to the user, I need that when the user closes the video, the above function is executed by sending the value of its reward to the database, but always returns me an error :

videosInmobi() {
    let carregar = this.loading.create({content : "Carregando..."});
    carregar.present();
    let rewardConfig: AdMobFreeRewardVideoConfig = {
        isTesting: true,
        autoShow: true,
        id: 'ca-app-pub-8000726989219599/6974786599' //id videos InMobi
    };
    this.admob.rewardVideo.config(rewardConfig);
    this.admob.rewardVideo.prepare().then((result) => {
        carregar.dismissAll();
        this.recompensa.data = moment().format('L');
        this.recompensa.valor = 0.03;
        //tento fazer assim atualmente, porém ele sempre retorna um erro quando fecho o vídeo
        document.addEventListener('admob.rewardvideo.events.CLOSE', function(event) {
            console.log(event)
            this.addReward(this.recompensa);
        })
    }), carregar.dismissAll();   
}

the error that returns me is from the image below :

Answer 1

Directly answering the question:

How to call a function within an addeventlistener?

Eventtarget.addeventlistener() needs at least two parameters. One type of event and a Listener, which can be an Eventlistener-like object or, more simply, a function as in the example below.

const element = document.querySelector('.js-button')

element.addEventListener('click', function() {
  alert('Obrigado!')
})

<div class="js-button"> CLICA EM MIM </div>

Responding to the context:

The error in your code is in calling a this.addReward that does not exist. If you give a console.log to this inside addeventlistener you will see that this method does not exist because this corresponds to the context of the System.

document.addEventListener('admob.rewardvideo.events.CLOSE', function(event) { console.log(event) this.addReward(this.recompensa); })

I don’t know how your code is formatted but maybe just call addReward(this.recompensa) resolve.