Adding Custom Element for Ionic Modals

Adding dynamic features to a static site.

This is a multi part series covering all the different types of Web Components I am using on the https://ajonp.com site currently. I just wanted to show how you can use each of them at a somewhat high level.

I was inspired to share more by Max's post:

Why We Use Web Components

Max Lynch for Ionic ・ Jul 8 '19

#webcomponents #shadowdom #ionicframework #stencil

Adding Web Component for Ionic Modals

So for this Web Component we are going to code a Custom Element from scratch, not using Stencil, Polymer, or Angular.

This just builds a simple search modal that allows for Algolia search searchResults:

Modal Code

I don’t know if I can add much more than what Eric Bidelman wrote for Custom Elements. I would just say you can basically put anything in them, just make sure you have the connectedCallback() in place if you need to run code each iteration.

connectedCallback: Called every time the element is inserted into the DOM. Useful for running setup code, such as fetching resources or rendering. Generally, you should try to delay work until this time.

customElements.define(
  'modal-search',
  class extends HTMLElement {
    constructor() {
      super();
      this.attachShadow({ mode: 'open' });
    }
    connectedCallback() {
      const ionHeader = document.createElement('ion-header');
      const ionToolbar = document.createElement('ion-toolbar');
      const ionTitle = document.createElement('ion-title');
      ionTitle.innerHTML = `<ion-label color='primary'>Search Purr-fectly</ion-label>`
      const ionButtons = document.createElement('ion-buttons');
      ionButtons.setAttribute('slot', 'primary');

      const ionButton = document.createElement('ion-button');
      ionButton.addEventListener('click', async () => {
        const modalController = document.querySelector('ion-modal-controller');
        await modalController.dismiss({
          'dismissed': true
        });
      })

      const ionIconClose = document.createElement('ion-icon');
      ionIconClose.setAttribute('slot','icon-only');
      ionIconClose.setAttribute('name', 'close');

      ionButton.appendChild(ionIconClose);
      ionButtons.appendChild(ionButton);
      ionToolbar.appendChild(ionButtons);

      ionToolbar.appendChild(ionTitle);
      ionHeader.appendChild(ionToolbar);

      const ionSearchbar = document.createElement('ion-searchbar');
      const searchContent = document.createElement('ion-content');
      ionSearchbar.addEventListener('ionChange', async ev => {
        try {
          const searchResults = await index.search({ query: ev.detail.value });
          const ionList = document.createElement('ion-list');
          searchResults.hits.forEach(hit => {
            const ionItem = document.createElement('ion-item');
            ionItem.setAttribute('href', hit.url);
            const ionLabel = document.createElement('ion-label');

            const title = document.createElement('h2');
            title.innerHTML = hit._highlightResult.title.value;
            ionLabel.appendChild(title);
            const summary = document.createElement('p');
            summary.innerHTML = hit._highlightResult.summary.value;
            ionLabel.appendChild(summary);

            ionItem.appendChild(ionLabel);
            ionList.appendChild(ionItem);
          });
          searchContent.innerHTML = ionList.innerHTML
        } catch (err) {
          console.log(err);
          console.log(err.debugData);
        }
      });
      this.shadowRoot.appendChild(ionHeader);
      this.shadowRoot.appendChild(ionSearchbar);
      this.shadowRoot.appendChild(searchContent);
    }
  }
);

Event Listener for 🔍️

This is utilizing Ionic’s Modal. Please also not you MUST include the <ion-modal-controller> in your site or this will not work (trust me lost hours of my life on that one)!

Notice in modalController.create we are passing a component: 'modal-search' property. This is the name of custom element that we created above.

mainSearch.forEach(b => {
  b.addEventListener('click', async event => {
    // initialize controller
    const modalController = document.querySelector('ion-modal-controller');
    await modalController.componentOnReady();

    // present the modal
    const modalElement = await modalController.create({
      animated: true,
      component: 'modal-search',
      componentProps: {
        search: event.currentTarget.getAttribute('search')
      }
    });
    await modalElement.present();
  });
});

The BEST Part

Now I could package this up and add it to NPM as a nice package. Better yet we could create it from a Stencil component next.

Let me know what you think!