The coherent-gameface-carousel is part of the Gameface custom components suite. As most of the components in this suite it uses slots to allow dynamic content.

Usage

The coherent-gameface-carousel component comes with UMD and CJS builds.

Usage with UMD modules:

<script src="./node_modules/coherent-gameface-carousel/dist/carousel.production.min.js"></script>

• add the coherent-gameface-carousel component to your html:

<gameface-carousel>
    <div slot="carousel-content">0</div>
    <div slot="carousel-content">1</div>
    <div slot="carousel-content">2</div>
    <div slot="carousel-content">3</div>
    <div slot="carousel-content">4</div>
    <div slot="carousel-content">5</div>
    <div slot="carousel-content">6</div>
    <div slot="carousel-content">7</div>
</gameface-carousel>

This is all! Load the file in Gameface to see the coherent-gameface-carousel.

Usage with JavaScript:

If you wish to import the modules using JavaScript you can remove the script tags which import the components and the coherent-gameface-carousel from the node_modules folder and import them like this:

import { Carousel } from 'coherent-gameface-carousel';

or simply

import 'coherent-gameface-carousel';

Note that this approach requires a module bundler like Webpack or Rollup to resolve the modules from the node_modules folder.

Public API

Properties

currentItemIndex

This is the index of the active item. It returns a number. You can set it and the carousel will scroll to the specified element. You must pass a number corresponding to an existing item in the carousel.

document.querySelector('gameface-carousel').currentItemIndex = 0;

When the currentItemIndex is modified, the carousel will automatically apply the carousel-current-item class to the active item. This class is available for styling purposes on the active item.

items

Returns an array of HTMLElements - the carousel items. Setting it will replace all current items with the ones from the array.

document.querySelector('gameface-carousel').items = [HTMLElementInstance, HTMLElementInstance1, HTMLElementInstanceN, ...];

currentPage

Returns the index of the currently active page. Setting it will scroll the carousel to specified page.

document.querySelector('gameface-carousel').currentPage = 1;

Available Slots

carousel-content

The carousel supports a dynamic slot that is supposed to hold its items - carousel-content. To add an item into this slot specify its slot attribute:

<div slot="carousel-content">7</div>

All elements that have this slot attribute will be initially added to the carousel.

carousel-next and carousel-previous

These slots are reserved for the navigation controls that change the currently active carousel items. By default they are right and left pointing arrows. Set the slot attribute to next or previous to an element to use custom navigation controls:

<gameface-carousel>
    <button slot="carousel-next">Next</div>
    <button slot="carousel-previous">Prev</div>
<gameface-carousel>

Adding items to the carousel

addItem(element, index)

Use the addItem method to add a new item:

Parameters

• element - the new carousel item that should be added
• [index] - the index at which to add the new item

const carouselItem = document.createElement('div');
carouselItem.textContent = 'Hello, there!';

document.querySelector('gameface-carousel').addItem(carouselItem);

Removing items from the carousel

removeItem(index)

Use the removeItem method to remove an item:

Parameters

• [index] - the index of the item that is to be removed, if omitted - will remove the first element

document.querySelector('gameface-carousel').removeItem();

Updating the page size

Use the pageSize setter to change the number of simultaneously visible elements.

document.querySelector('gameface-carousel').pageSize = 3;

Navigating the carousel

Sometimes it may be necessary to navigate the carousel programmatically. This can be achieved by using the next() and previous() properties of the carousel.

For example if we want to use the mouse scroll to navigate:

document.querySelector('gameface-carousel').addEventListener('wheel', (e) => {               
    if (e.deltaY > 0) {
        document.querySelector('gameface-carousel').next();
    } else {
        document.querySelector('gameface-carousel').previous();
    }
});

Or if we want to use the left and right keyboard keys:

document.addEventListener('keydown', (e) => {
    if (e.keyCode === 39) {
        document.querySelector('gameface-carousel').next();
    }
    
    if (e.keyCode === 37) {
        document.querySelector('gameface-carousel').previous();
    }
});

Limitations

Currently all items in the carousel must have the same width and height otherwise the component will not be properly resized.

Usage with data-bindings (Coherent Gameface only)

Using the carousel component with data-binding is straightforward.

We add our data-bindings to the <component-slot> like this:

<gameface-carousel class="carousel-component">
    <div
        slot="carousel-content"
        class="box"
        data-bind-for="item:{{carousel.items}}"
    >
    <div 
        data-bind-value="{{item.id}}"
        data-bind-style-background-color="{{item.color}}">
        </div>
    </div>
</gameface-carousel>

And then we need to re-render the controls:

document.querySelector('gameface-carousel').rerenderControls();

The reason we do that is because, the carousel will intialize before the data-binding and the control won't be rendered properly. The same principle applies every time we change the number of elements in the model, since the carousel controls won't be changed automatically.