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JavaScript JavaScript and the DOM Making Changes to the DOM Remove Nodes

lythila
lythila
2,958 Points
Posted by lythila
lythila
2,958 Points

One step further - hiding the remove button when there are no more items

Hello!

I wanted to test my learnings and go one step further and hide the remove task button once there were no more items in the list and then reshow it once an item was added.

Based on the information from this track does this seem like an efficient solution or is there a better way to do this?

const btnCreate = document.querySelector('.btn-main');
const btnToggle = document.querySelector('.btn-toggle');
const btnRemove = document.querySelector('.btn-remove');
const elements = document.querySelector('ul').getElementsByTagName('li');

btnCreate.addEventListener('click', () => {
 const input = document.querySelector('.input-main');
 const list = document.querySelector('ul');

 list.insertAdjacentHTML(
  'afterbegin',
   `<li>${input.value}</li>`
 );
 input.value = '';

 if (btnRemove.style.display === 'none') {
   btnRemove.style.display = 'block';
 }
});

btnToggle.addEventListener('click', () => {
  const listContainer = document.querySelector('.list-container');

  if (listContainer.style.display === 'none') {
    btnToggle.textContent = 'Hide List';
    listContainer.removeAttribute('style');
  } else {
    btnToggle.textContent = 'Show List';
      listContainer.style.display = 'none';
  }
});

btnRemove.addEventListener('click', () => {
  const lastItem = document.querySelector('li:last-child');
  lastItem.remove();

  if (elements.length === 0) {
    btnRemove.style.display = 'none';
  }
});

2 Answers

Steven Parker
Steven Parker
231,198 Points
Steven Parker
Steven Parker
231,198 Points

It seems a bit awkward to handle button display different ways at different times. So instead of completely removing the "style" attribute in one handler, you might just set style.display to "block" as is done in the other handler.

This can lead to a small efficiency improvement, as you won't have to test if it is already "none" when you want it to be "block".

lythila
lythila
2,958 Points
lythila
lythila
2,958 Points

Ohhh I see what you're saying! That makes a lot of sense. Thanks for the input!!