How to Design a Toggle
A toggle is a control that can be either on or off. It is common in modern interfaces.
However, the use of a toggle is not always appropriate. There are many cases where it may be better to use a button instead. Toggles are notoriously confusing for users and can cause frustration. They are often a poor choice when the control should be obvious or have a specific purpose. For example, using a toggle to download content is a bad idea because downloading only happens once and turning the toggle off doesn’t undownload it.
When used correctly, a toggle can be very effective for users. They enforce a mutually exclusive state and are easy to understand when placed in context. Toggles also allow for a large number of possible configurations to be made within a limited space. However, there are some important things to consider when designing a toggle.
First, it is essential to consider accessibility. Toggles are commonly inaccessible for users with disabilities. This can be due to lack of awareness amongst web developers and designers or intentional design decisions that don’t make a toggle accessible. For instance, using the color red to indicate an “on” state is counterintuitive for users with color blindness and can be a major source of confusion. Additionally, it’s crucial to use high contrast colors to indicate the state of a toggle. In addition to this, it is important to think about cultural and societal implications of the states you choose for your toggles. For example, the YMCA has a guide for accessibility and has found that using white as a default for an “on” state is not the best option for people with color blindness because they often confuse white and green as the same color.
There are several approaches to managing feature flags ranging from the use of the preprocessor’s #ifdef feature through to more sophisticated and dynamic solutions like code snippets and plugins. The most important thing to remember when choosing a method for managing toggles is that it needs to be flexible enough to allow for the dynamic in-memory re-configuration of the toggle. This can be a critical factor when running experimentation on an application since it can dramatically reduce the amount of time needed to test new feature variants by avoiding the need to re-deploy the artifact in order to swap the toggle between different paths.
Savvy teams view the Feature Toggles in their codebase as inventory which comes with a cost and they seek to keep this inventory as low as possible. One way to do this is to implement an “expiration date” for each toggle which will trigger a manual removal task on the team’s backlog when the toggle is no longer needed. This prevents the accidental re-introduction of a toggle which could introduce bugs or confusion. Other teams go so far as to create a time bomb which will fail an automated test if a toggle is still in place after the expiration date.