Fix Menu Anchor Loss On Resize In Equinor Design System

Have you ever experienced the frustration of a menu component detaching from its anchor point when you resize your screen or switch your mobile device from portrait to landscape mode? It's a common issue, especially in responsive design systems, and we're going to dive deep into why this happens and, more importantly, how to fix it. This article will explore the problem within the Equinor Design System, but the concepts and solutions discussed are applicable to many React-based UI libraries.

The Problem: Menu Component Misalignment

Let's talk about the menu component issue. Imagine you're using a sleek menu component that's perfectly anchored to a specific element on your page. Everything looks great, right? But then, you resize your browser window or, if you're on a mobile device, you rotate your screen. Suddenly, the menu is no longer aligned with its anchor. It's floating off in some random corner of the screen, looking completely out of place. This is exactly the problem reported within the Equinor Design System, and it's a headache for both developers and users.

This misalignment occurs because the menu's position is initially calculated based on the viewport's dimensions and the anchor element's location. When the viewport changes, this calculation becomes outdated, and the menu needs to be repositioned. The core of the issue lies in how the menu component tracks and responds to these changes. Without a mechanism to dynamically update its position, the menu will remain stuck at its initial coordinates, leading to the dreaded misalignment. For users, this translates to a broken and confusing experience. Imagine trying to navigate a website on your phone, only to have the menus jump around every time you switch from portrait to landscape. It's not just visually unappealing, it actively hinders usability. Therefore, fixing this issue is crucial for creating a robust and user-friendly design system.

Steps to Reproduce the Issue

To really understand the problem, it's helpful to reproduce the menu behavior ourselves. Here’s how you can replicate this issue, specifically within the Equinor Design System context, but adaptable to other React-based systems:

1. Mobile Device Testing: The easiest way to see this in action is on a mobile device. This is because orientation changes (portrait to landscape and vice versa) trigger the screen resize event that causes the problem.
2. Open a View with a Menu: Navigate to a part of your application that uses the Menu component. This menu should be anchored to a specific element on the page – think of a dropdown menu attached to a button or an options panel linked to an icon.
3. Switch Device Orientation: While the menu is open and visible, rotate your mobile device from portrait to landscape or back again. This will force a screen resize event.
4. Observe the Misalignment: You'll likely see the menu jump away from its anchor element. It might appear in a completely different part of the screen, overlap other elements, or simply be positioned incorrectly.

By following these steps, you can directly witness the issue. This hands-on approach makes it easier to grasp the problem's impact and appreciate the need for a solution. It’s one thing to read about a bug; it’s another to see it happen right in front of you. This reproduction method is also valuable for testing the effectiveness of any proposed fixes. Once you've implemented a solution, you can repeat these steps to ensure the menu now stays anchored correctly during screen resizes.

Expected Behavior: Staying Anchored

So, what should happen when the screen resizes? Let's define the expected behavior of the menu. Ideally, the menu component should automatically adjust its position to remain correctly anchored to its trigger element, regardless of screen size changes. This means that when you rotate your device or resize the browser window, the menu should seamlessly reposition itself, maintaining its visual connection to the element that opened it. This behavior is crucial for a consistent and intuitive user experience.

Imagine a user interacting with a website on their tablet. They tap a button to open a menu, and then they rotate their device to get a better view. If the menu behaves as expected, it will smoothly reposition itself alongside the button, allowing the user to continue their task without interruption. However, if the menu detaches and floats away, the user will be momentarily disoriented. They might have to hunt for the menu, re-open it, or even refresh the page – all of which are frustrating and time-consuming. Therefore, the expected behavior is not just a nice-to-have feature; it's a fundamental aspect of a well-designed user interface. It ensures that the interface remains predictable and responsive, empowering users to interact with the application confidently. By prioritizing this behavior, we can create a more polished and user-friendly experience for everyone.

Possible Cause: Floating-UI and autoUpdate

Let's get technical and explore a possible cause of the menu misalignment. The issue seems to be related to a library called Floating UI, specifically its React implementation (floating-ui/react). Floating UI is a popular library for creating floating elements like menus, tooltips, and popovers. It handles the complex calculations needed to position these elements correctly, taking into account factors like viewport boundaries and element collisions. However, like any library, it needs to be configured correctly to work as expected.

According to the Floating UI documentation, there's a setting called autoUpdate that can address this very issue. When enabled, autoUpdate automatically repositions the floating element whenever its anchor element changes size or position, or when the viewport changes. This is precisely the behavior we need to ensure the menu stays anchored during screen resizes. The documentation suggests using the whileElementsMounted option for components that are conditionally rendered. This option ensures that the auto-update mechanism is active only when both the anchor and the floating element are present in the DOM. However, there's a caveat. This behavior might not be suitable for all scenarios. For instance, if the menu is always rendered, regardless of its visibility, whileElementsMounted might not be the optimal choice. This is why the proposed solution involves making this behavior configurable. By exposing an option to control the autoUpdate setting, developers can fine-tune the menu's behavior to fit their specific needs.

Proposed Solution: Expose a Configurable Prop

Okay, so we know the problem and a potential cause. Now, let's talk about the proposed solution for menu alignment. The suggestion is to expose a prop, perhaps named whileElementsMounted or an autoUpdate toggle, on the MenuProps interface. This would give developers the flexibility to control the auto-update behavior of the menu component. By making this configurable, we can cater to different use cases and ensure the menu works correctly in various scenarios.

For example, if a menu is conditionally rendered (appearing only when a button is clicked), setting whileElementsMounted to true would be the ideal solution. This would ensure that Floating UI automatically updates the menu's position whenever the viewport changes, keeping it anchored to its trigger element. On the other hand, if a menu is always rendered, but its visibility is toggled, a different approach might be needed. In this case, developers might prefer to manually trigger updates or use a different auto-update strategy. By exposing a configurable prop, we empower developers to make these choices and optimize the menu's behavior for their specific application. This approach aligns with the principles of a well-designed component library. It provides a balance between ease of use and flexibility, allowing developers to adapt the component to their needs without sacrificing simplicity. This also prevents introducing breaking changes or unexpected behavior for existing users of the component.

Environment and Additional Notes

To give you the full picture, here's some context about the environment where this issue was observed:

• Affected Package: @equinor/eds-core-react (This indicates the specific package within the Equinor Design System where the menu component resides.)
• Browsers: Mobile Safari / Chrome (This highlights that the issue is prevalent on mobile browsers, likely due to the frequent orientation changes on these devices.)
• Device: Mobile (orientation changes) (This reinforces the role of mobile devices and orientation changes in triggering the bug.)

This information helps pinpoint the problem's scope and prioritize the fix. Knowing that the issue affects mobile browsers is crucial, as it suggests that users on these devices are more likely to encounter the bug. The fact that it was reported within @equinor/eds-core-react helps developers focus their efforts on the relevant codebase.

Additionally, the bug was initially reported on a Slack channel dedicated to the EDS design system by Marius Backer. This highlights the importance of communication channels within development teams. By providing a platform for reporting issues and discussing solutions, teams can collaborate more effectively and resolve problems faster. The report also included a link to the Floating UI documentation, specifically the section on autoUpdate. This demonstrates the value of referencing external resources and documentation when troubleshooting issues. By sharing this information, the reporter helped guide the investigation and suggested a potential solution. This collaborative approach is essential for maintaining a healthy and efficient development process.

Conclusion: A Path to a More Stable Menu

The issue of menu anchor loss on screen resize is a common challenge in responsive web design, but it's one that can be effectively addressed with the right approach. By understanding the underlying cause, leveraging libraries like Floating UI, and providing developers with the flexibility to configure component behavior, we can create more robust and user-friendly interfaces. The proposed solution of exposing a configurable prop for auto-update behavior is a step in the right direction for the Equinor Design System, and it offers valuable lessons for any team building UI components.

By tackling this issue head-on, we not only improve the stability and reliability of our menus but also enhance the overall user experience. A menu that stays anchored is a menu that empowers users to navigate and interact with our applications seamlessly, regardless of their device or screen size. And that's a goal worth striving for.