I am trying to create a single page todo app with plain javascript. There is a button on the page that takes the text value from textbox and creates a button with that input value. What I am trying to do is passing a button's text value, which is created by user dynamically, to another element, a h2 element for example. Here are screenshots to explain what I mean;

Type a list name and click Create List button;

A button is created with the input text value. Now when you click the List 1 button, text value of that button, "List 1", should pass to h2 element on the right;

Here is my code so far;

<div class="container" id="table-and-list-names">
  <div class="row">
    <div class="col-3">
      <ul class="nav flex-column" id="list-names">
        <!--Names of Lists created by user will be here-->
      </ul>
    </div>

    <!--TABLE-->
    <div class="col-9">
      <h2 id="current-list-name">Select Todo List</h2>
      //...

Create button;

export function createButton(listName) {
    const listOfLists = document.querySelector('#list-names');
    const newList = document.createElement('li');
    const newListButton = document.createElement('button');
   
    newListButton.classList.add("btn", "btn-sm", "btn-outline-primary", "created-list");

    newListButton.innerText = listName;

    newList.appendChild(newListButton);
    listOfLists.appendChild(newList);
}

I tried to pass the text value with this code but didn't work;

const currListName = document.querySelector('#current-list-name');

var buttons = document.getElementsByClassName('.created-list');
var buttonCount = buttons.length;

for (var i = 0; i <= length; ++i)
    buttons[i].onClick = function(e) {
        currListName.textContent = buttons[i].textContent;
    };

Nothing happens when I click the button, no errors on the browser console. I only get an error when I refresh the page and it says "Uncaught TypeError: can't access property "onClick", buttons[i] is undefined". I think that is because there is no button when I refresh the page. Any suggestions?