Patrick H. Lauke
8dbd24699f
Logically moves the various `role` and `aria-` attributes to the `.progress` element itself, leaving the `.progress-bar` to be used purely for the visual presentation. This fixes the problem #36736 that in certain browser/AT combinations, zero-value/zero-width progress bars are completely ignored and not announced. For multiple/stacked progress bars, this PR introduces a new wrapper and class `.progress-stacked`, to accommodate for the fact that with the more logical structure above, we need full `.progress` elements with child `.progress-bar` elements, and can't get away with the fudge we had before of having a single `.progress` with multiple `.progress-bar`s. Note that the old markup structures still work with this change, so this could be considered a non-breaking change - though one we definitely want to highlight as it's more accessible (as it now guarantees that zero-value/zero-width progress bars, whether on their own or as part of a multi/stacked bar, are actually announced)
7.6 KiB
layout, title, description, group, toc
| layout | title | description | group | toc |
|---|---|---|---|---|
| docs | Progress | Documentation and examples for using Bootstrap custom progress bars featuring support for stacked bars, animated backgrounds, and text labels. | components | true |
How it works
Progress components are built with two HTML elements, some CSS to set the width, and a few attributes. We don't use the HTML5 <progress> element, ensuring you can stack progress bars, animate them, and place text labels over them.
- We use the
.progressas a wrapper to indicate the max value of the progress bar. - The
.progresswrapper also requires arole="progress"andariaattributes to make it accessible, including an accessible name (usingaria-label,aria-labelledby, or similar). - We use the inner
.progress-barpurely for the visual bar and label. - The
.progress-barrequires an inline style, utility class, or custom CSS to set its width. - We provide a special
.progress-stackedclass to create multiple/stacked progress bars.
Put that all together, and you have the following examples.
{{< example >}}
Bootstrap provides a handful of [utilities for setting width]({{< docsref "/utilities/sizing" >}}). Depending on your needs, these may help with quickly configuring progress.
{{< example >}}
Labels
Add labels to your progress bars by placing text within the .progress-bar.
{{< example >}}
Height
We only set a height value on the .progress, so if you change that value the inner .progress-bar will automatically resize accordingly.
{{< example >}}
Backgrounds
Use background utility classes to change the appearance of individual progress bars.
{{< example >}}
{{< callout info >}} {{< partial "callout-warning-color-assistive-technologies.md" >}} {{< /callout >}}
Multiple bars
You can include multiple progress components inside a container with .progress-stacked to create a single stacked progress bar. Note that in this case, the styling to set the visual width of the progress bar must be applied to the .progress elements, rather than the .progress-bars.
{{< example >}}
Striped
Add .progress-bar-striped to any .progress-bar to apply a stripe via CSS gradient over the progress bar's background color.
{{< example >}}
Animated stripes
The striped gradient can also be animated. Add .progress-bar-animated to .progress-bar to animate the stripes right to left via CSS3 animations.
{{< example >}}
CSS
Variables
{{< added-in "5.2.0" >}}
As part of Bootstrap's evolving CSS variables approach, progress bars now use local CSS variables on .progress for enhanced real-time customization. Values for the CSS variables are set via Sass, so Sass customization is still supported, too.
{{< scss-docs name="progress-css-vars" file="scss/_progress.scss" >}}
Sass variables
{{< scss-docs name="progress-variables" file="scss/_variables.scss" >}}
Keyframes
Used for creating the CSS animations for .progress-bar-animated. Included in scss/_progress-bar.scss.
{{< scss-docs name="progress-keyframes" file="scss/_progress.scss" >}}