Materializecss 1.0

i successfully implemented to use materializecss 1.0 ion my ionc3 project.

but when i try to use it i get this error

Unhandled Promise rejection: – "invalid views to insert" – "; Zone:" 
– "<root>" – "; Task:" – "Promise.then" – "; Value:" – 
"invalid views to insert" – undefined

for intilizate the materialize tab i use this code in the .ts file

var tabs = document.querySelectorAll('.tabs')
    console.log(" tabs ", tabs[i])
    for (var i = 0; i < tabs.length; i++){
      console.log(" tab ", tabs[i])

this for the html file

<div class="row">
        <div class="col s12">
            <ul class="tabs">
                <li class="tab col s3"><a href="#compl">Completate</a></li>
                <li class="tab col s3"><a class="active" href="#nocompl">Non Completate</a></li>
        <div id="compl" class="col s12">
                <ion-item *ngFor="let item of praticheComp">
                    <h4 item-start>{{ item.IDPratiche }}</h4>
                    <h3> - {{ item.NomeServizio }}</h3>

        <div id="nocompl" class="col s12">
                <ion-item-sliding *ngFor="let item of praticheNoComp">
                    <ion-item (click)="itemSelected(item)">
                        <h4>{{ item.IDPratiche }} - {{ item.NomeServizio }}</h4>
                    <ion-item-options side="right">
                        <button ion-button (click)="itemSelected(item)">
                      <ion-icon name="text"></ion-icon>
                        <button ion-button color="danger" (click)="itemDeleted(item)"><ion-icon name="trash"></ion-icon> Cancella</button>



some help for this problem ?