JavaScript- Hold Shift to Check Multiple Checkboxes!

So I am back after another tough challenge from Wes Bos's JavaScript30! Today's challenge was much more work than I first assumed. Holding shift to check multiple boxes is such a common practice I was surprised to see that it isn't built in to websites automatically and that you had to manually code it yourself. Obviously if that was the case then this lesson wouldn't exist but you know what I mean.

With full transparency I gave up and followed along with Wes for this lesson. The video even started with him encouraging us to take the reigns and figure it out ourselves. After over an hour and a half of googling and attempting any kind of real progress I gave up and followed along with this lesson. I'm not proud of giving up on this one but I was definitely falling down a rabbit-hole of irrelevant information and I doubt I would have came up with an actual solution anytime this week! So yeah...with my head low I followed along with Wes.

This lesson is very self explanatory. You are given a basic checklist and then are asked to make it possible to check multiple boxes by holding down shift while checking a box. Cool. This turned out to be much more complicated than I thought. Before we dive into the actual lesson and what was necessary on our part there is one thing I do want to call out.

    input:checked + p {
      background: #F9F9F9;
      text-decoration: line-through;
    }

This very simple line of CSS was cool to me. I knew it was possible to make a checkbox with HTML with but I was not aware that you can change the properties of the checkbox/the div the checkbox is in with CSS just by checking the box. I also want to note here that Wes also mentioned how often he said the word "check" because it was a lot in the video...fair warning it will be just as much in this post.

  let log = document.querySelector('#log');
  document.addEventListener("click", logKey)
  function logKey(e) {
    console.log(`The shift key is pressed: ${e.shiftKey}`);}

function validate() {
  if (document.getElementsByClassName('item').checked) {
    alert('checked');
  } else { alert('you didnt check it!')} }
validate()  
  let checkBoxes = document.querySelectorAll('checkbox');
  let selected = [];
  for (let i=0; i < checkBoxes.length; i++) {
    if (checkBoxesp[i].checked) {
      selected.push(checkBoxes[i].value)} }

Everything in the code block above this line was a failure. These were just a few of my attempts at trying to figure out the solution myself. I did feel as if I was on the right track a few times. For example the first part with function logKey(e) I was so proud for finding how to call when the shift key was pressed during a click and when it was not. After that...I couldn't even guess how to proceed. Again I was stuck.

const checkboxes = document.querySelectorAll('.inbox input[type="checkbox"]')
let lastChecked

function handleCheck(e) {
  let inBetween = false
if (e.shiftKey && this.checked){
  checkboxes.forEach (checkbox => {
    console.log(checkbox)
    if (checkbox === this || checkbox === lastChecked) {
      inBetween =!inBetween;
    }
    if(inBetween) {
      checkbox.checked = true
    }
  })
}
  lastChecked = this;
}
checkboxes.forEach(checkbox => checkbox.addEventListener('click', handleCheck));

Wes was here to save the day with this. He did state it would be possible to check multiple boxes by calling the parent/child in the HTML, but this could be easily broken by changes made to the HTML. Instead he had us use a for loop, or at least a forEach. This did make a lot of sense to me. It is a fairly simple way to go through each part of the HTML while checking if a box was checked along the way. That was just half the battle though.
After using forEach we had to make a new variable to determine which element was between the first element checked and the last element checked. This would be how we would check the remaining boxes and change their properties to reflect that of the elements that were initially checked. There were so many lines here that had me a little lost...again using the || and using an ! before a variable are strange concepts to me. I have to look into them more before my next project.
Before I knew what was happening somehow we already finished the challenge. It just worked. It was in that moment that I saw that this challenge was much more simple than I thought. It wasn't that much code when all is said and done. Being able to use all the parts together was the complicated part. I might have been able to solve this myself, but even in saying that, I doubt I could have come up with a viable solution by the end of this week.
Well, that about wraps up this post! Today's lesson wasn't the best for me, but it was a good reminder that I still have a long long way to go. I hope you come back to check out my next post with the next part of Wes Bos's JavaScript 30 with - 11 Custom HTML5 Video player!

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