When to use this component
Use product alerts to tell the user about something they need to know about, but that’s not directly related to the page content, for example:
A significant situation, such as a site-wide service disruption, or other critical information that will impact most users
Important recent or upcoming changes to a process or service
When not to use this component
Do not use product alerts to tell the user about validation errors – Use In-line alerts instead
Do not use product alerts for information that is directly relevant to the thing the user is doing on that page – Use Page alerts instead
Do not use product alerts just for styling regular content (for emphasis or highlighting)
Best practices
Do
Write concise headings and copy
Place product alerts at the top of the page above the main heading or global header bar, as applicable
Remove alert text once the issue is resolved or enough time has passed that the information provided is no longer new
Describe the impact on the user
Use product alerts sparingly to avoid alert fatigue
Use an appropriate status – Please see the Alerts article
Don’t
Stack product alert banners
Tips
Consider how tall the product alert banner will appear on mobile screens
Since product alerts can impact the visibility of other content, use a link or call to action to direct users to further information, as needed
Accessibility
The WCAG criteria outlined in this section were chosen because they represent some of the most common failures when designing and implementing these components. For a comprehensive list, please see Web Content Accessibility Guidelines (WCAG) 2.1 (w3.org).
1.4.3 Contrast (Minimum)
The intent of this success criterion is to provide enough contrast between text and its background so that it can be read by people with moderately low vision (who do not use contrast-enhancing assistive technology). Text that is larger and has wider character strokes is easier to read at lower contrast. The contrast requirement for larger text is therefore lower.
It is recommended to check colour contrast between the text and background using a contrast checking tool like the one provided by WebAIM WebAIM: Contrast Checker.
Understanding Success Criterion 1.4.3: Contrast (Minimum) | WAI | W3C
1.4.11 Non-text Contrast
The intent of this success criterion is to ensure that active user interface components (i.e., controls) and meaningful graphics are distinguishable by people with moderately low vision. Low contrast controls are more difficult to perceive, and may be completely missed by people with a visual impairment.
It is recommended to check that UI components have a contrast ratio of at least 3:1 against adjacent colours using a contrast checking tool like the one provided by WebAIM WebAIM: Contrast Checker.
Tip: There are contrast checking features built into some automated accessibility testing tools. However, these tools are not always capable of checking the contrast of different UI component states. For instance, if your page alert uses a dismiss button, it is recommended to manually test the contrast of its hover and focused states.
Understanding Success Criterion 1.4.11: Non-text Contrast | WAI | W3C
4.1.3 Status Messages
This criterion requires that, in content implemented using markup languages, status messages can be programmatically determined through role or properties such that they can be presented to the user by assistive technologies without receiving focus.
The intent of this success criterion is to make users aware of important changes in content that are not given focus, and to do so in a way that doesn't unnecessarily interrupt their work.
The intended beneficiaries are blind and low vision users of assistive technologies with screen reader capabilities.
Understanding Success Criterion 4.1.3: Status Messages | WAI | W3C
Key component features
Telerik provides four built-in notification types that can be modified for use as product alerts: error, warning, info and success. They also offer the option to define your own type by customizing the template and setting options for size, colour and position.
Blazor Notification Demos - Overview | Telerik UI for Blazor
Examples
Note: The following example is a visual illustration of how this component could be used in a MAACE application. Live examples of the Telerik UI component implemented in MAACE applications will be added when available.
Resources
Government of Canada resources
Contextual alerts - Canada.ca design pattern - Canada.ca
Alert fatigue during COVID-19 | Canada.ca blog
External resources
Critical alerts | Ontario Design System
Notification banner – GOV.UK Design System (design-system.service.gov.uk)