svelte-progress-bar

The idea is a little Svelte component that shows a cool progress bar, like what's on YouTube, or this cool thing.

If you're using it in your JavaScript, you'd probably have something like:

const ProgressBar = require('svelte-progress-bar')
const progress = new ProgressBar({
    // you need to 'attach' it to some element on the page
    target: document.querySelector('#my-progress-bar')
})

Then if you were using some sort of single-page app with a page/state change event emitter, it might look like:

const router = // some sort of page/state change event emitter
router.on('stateChangeStart', () => {
    progress.start()
})
router.on('stateChangeEnd', () => {
    progress.complete()
})

Or if you had some progress event emitter that actually told you the percent of progress, you might set the progress bar width manually with something like this:

const dataLoad = // some sort of data load progress event emitter
dataLoad.on('percentDone', percent => {
    progress.set({ width: percent / 100 }) // must be a ratio
})
dataLoad.on('end', () => {
    progress.complete()
})

Or if you are using the progress bar inside a Svelte template, you might use it like this:

<ProgressBar width="{{width}}" />

<script>
import ProgressBar from 'svelte-progress-bar'
export default {
    components: { ProgressBar }
    // somewhere later: this.set({ width: 0.4 })
}
</script>

bar color

The progress bar does not have a default color, so you will need to set one. You can either set the color as a data property or override the CSS.

JavaScript:

const progress = new ProgressBar({
    target: document.querySelector('#my-progress-bar'),
    data: { color: 'blue' }
})

Svelte component:

<ProgressBar width="{{width}}" color="blue" />

CSS:

.svelte-progress-bar, .svelte-progress-bar-leader {
    background-color: blue;
}
.svelte-progress-bar-leader {
    color: blue;
}

other styles

If you are using some type of navbar at the top of the page, like Bootstrap's, it is likely that you will need to change the z-index to get the progress bar to appear over the navbar:

.svelte-progress-bar {
    z-index: 100;
}
.svelte-progress-bar-leader {
    z-index: 101;
}

options

The properties available are:

• minimum (number, range: 0-1, default: 0.08): The starting percent width to use when the bar starts. Starting at 0 doesn't usually look very good.
• maximum (number, range: 0-1, default: 0.994): The maximum percent width value to use when the bar is at the end but not marked as complete. Letting the bar stay at 100% width for a while doesn't usually look very good either.
• intervalTime (number, default: 800): Milliseconds to wait between incrementing bar width when using the start (auto-increment) method.
• settleTime (number, default: 700): Milliseconds to wait after the complete method is called to hide the progress bar. Letting it sit at 100% width for a very short time makes it feel more fluid.

methods

These additional methods are available on an instantiated progress bar:

• start(): Set the width to the minimum and increment until maximum width.
• complete(): Set the width to 100% and then hide after settleTime.
• reset(): Set the width to minimum but do not start incrementing.
• continue(): Start incrementing from whatever the current width is.
• stop(): Stop incrementing and take no further action.

license

Published and released under the Very Open License.