StimulusJS Tag Component

form.html.erb

                <div class="mt-6">
                  <%= f.label :tags, class: 'form-label' %>
                  <div class="border border-gray-300 rounded-md flex-1 block w-full transition duration-150 ease-in-out pt-1.5 px-2 mt-1" data-controller="tags" data-tags-tag-collection data-tags-autocomplete="true" data-tags-show-dropdown="" data-target="tags.container">
                    <div class="flex flex-wrap cursor-text" data-action="click->tags#active">
                      <div class="flex flex-wrap" data-target="tags.tags">
                        <div class="text-sm p-2 bg-gray-100 rounded-md flex items-center space-x-1.5 mb-1.5 mr-2">
                          <p>tag</p>
                          <div class="inline-flex bg-gray-500 text-gray-100 rounded-full p-1 hover:bg-gray-700 cursor-pointer">
                            <svg class="h-3 w-3" fill="none" stroke-linecap="round" stroke-linejoin="round" stroke-width="2" viewBox="0 0 24 24" stroke="currentColor"><path d="M6 18L18 6M6 6l12 12"></path></svg>
                          </div>
                        </div>
                        <div class="text-sm p-2 bg-gray-100 rounded-md flex items-center space-x-1.5 mb-1.5 mr-2">
                          <p>stimulusjs</p>
                          <div class="inline-flex bg-gray-500 text-gray-100 rounded-full p-1 hover:bg-gray-700 cursor-pointer">
                            <svg class="h-3 w-3" fill="none" stroke-linecap="round" stroke-linejoin="round" stroke-width="2" viewBox="0 0 24 24" stroke="currentColor"><path d="M6 18L18 6M6 6l12 12"></path></svg>
                          </div>
                        </div>
                      </div>
                      <div class="mb-1.5 mr-2">
                        <%= text_field_tag :tags, nil, class: "text-sm appearance-none outline-none p-2", data: { target: "tags.input", action: "keyup->tags#inputTag keydown->tags#backspaceTag" } %>
                      </div>
                      <div class="hidden absolute text-gray-900 right-0 inset-y-0 flex items-center">
                        <svg class="h-4 w-4" fill="none" stroke-linecap="round" stroke-linejoin="round" stroke-width="2" viewBox="0 0 24 24" stroke="currentColor"><path d="M19 9l-7 7-7-7"></path></svg>
                      </div>
                    </div>
                    <%= f.hidden_field :tag_list, data: { target: "tags.data" } %>
                  </div>
                  <p class="input-hint">
                    Make your submission more discoverable with some tags.
                  </p>
                </div>

tags_controller.js

import { Controller } from "stimulus";

export default class extends Controller {
  static targets = ["input", "outer-input", "container", "tags", "data"];

  initialize() {
    // If we click outside the tag element we need to unfocus it
    document.addEventListener("click", (e) => {
      if (!this.containerTarget.contains(e.target)) {
        // Outside tags input has been clicked

        // If tag input has tag when unfocused make it a pill
        if (this.inputTarget.value.length > 0) {
          this.setTag(this.inputTarget.value);
        }
        this.containerTarget.classList.remove(
          "border-indigo-700",
          "shadow-outline-indigo"
        );
      } else {
        // Inside of tags input has been clicked
        this.containerTarget.classList.add(
          "border-indigo-700",
          "shadow-outline-indigo"
        );
      }
    });

    document.addEventListener("focusin", (e) => {
      if (this.inputTarget == e.target) {
        this.containerTarget.classList.add(
          "border-indigo-700",
          "shadow-outline-indigo"
        );
      }
    });

    document.addEventListener("focusout", (e) => {
      if (this.inputTarget == e.target) {
        // If tag input has tag when unfocused make it a pill
        if (this.inputTarget.value.length > 0) {
          this.setTag(this.inputTarget.value);
        }
        this.containerTarget.classList.remove(
          "border-indigo-700",
          "shadow-outline-indigo"
        );
      }
    });
  }

  connect() {
    this.renderTags();
  }

  active() {
    this.inputTarget.focus();
  }

  toggle(event) {
    event.preventDefault();
    this.formTarget.classList.toggle("hidden");
  }

  inputTag(event) {
    if (event.code === "Space" || event.code === "Comma") {
      this.tags = this.inputTarget.value;
      this.inputTarget.value = "";
      this.renderTags();
    }
  }

  setTag(tag) {
    this.tags = tag;
    this.inputTarget.value = "";
    this.renderTags();
  }

  backspaceTag(event) {
    if (event.code === "Backspace" && this.inputTarget.value === "") {
      console.log("backspaced!");
      this.removeLastTag();
    }
  }

  renderTags() {
    // get template, and render
    fetch("/tags/template.html")
      .then((response) => response.text())
      .then((html) => {
        let template = document.createElement("template");
        template.innerHTML = html;
        this.tagsTarget.innerHTML = "";
        this.tags.forEach((tag) => {
          let tagElem = template.content.cloneNode(true);
          let tagText = tagElem.querySelector("p");
          tagText.textContent = tag;
          this.tagsTarget.appendChild(tagElem);
        });
      });
  }

  removeTag(event) {
    // console.log(event.currentTarget.parentElement);
    let tag = event.currentTarget.parentElement.querySelector("p").textContent;

    if (tag !== null || tag !== undefined) {
      let tags = this.tags;
      let tagIndex = tags.indexOf(tag);
      tags.splice(tagIndex, 1);
      this.updateTags = tags;
      this.renderTags();
    }
  }

  removeLastTag() {
    let tags = this.tags;
    tags.splice(tags.length - 1, 1);
    this.updateTags = tags;
    this.renderTags();
  }

  set updateTags(tags) {
    this.data.set("tagCollection", JSON.stringify(tags));
    this.dataTarget.value = tags;
  }

  set tags(value) {
    // Maybe strip non text characters?
    let tag = value.toLowerCase().trim().replace(/,/g, "");
    let tags = this.tags;
    if (tags.indexOf(tag) === -1) {
      tags.push(tag);
      this.data.set("tagCollection", JSON.stringify(tags));
      this.dataTarget.value = tags;
    }
  }

  get tags() {
    return this.data.get("tagCollection")
      ? JSON.parse(this.data.get("tagCollection"))
      : [];
  }

  get dropdownActive() {
    return this.data.get("showDropdown") || false;
  }
}

template.html

<div
  class="text-sm p-2 bg-gray-100 rounded-md flex items-center space-x-1.5 mb-1.5 mr-2"
>
  <p></p>
  <div
    class="inline-flex bg-gray-500 text-gray-100 rounded-full p-1 hover:bg-gray-700 cursor-pointer"
    data-action="click->tags#removeTag"
  >
    <svg
      class="h-3 w-3"
      fill="none"
      stroke-linecap="round"
      stroke-linejoin="round"
      stroke-width="2"
      viewBox="0 0 24 24"
      stroke="currentColor"
    >
      <path d="M6 18L18 6M6 6l12 12"></path>
    </svg>
  </div>
</div>

https://twitter.com/i/status/1284766061586337792