Transitions are a powerful way to communicate a change in a user interface. They can be used in apps to help offload a lot of the cognitive work into the visual cortex: they help transport users between navigational contexts, explain changes in the arrangement of elements on a screen, and reinforce element hierarchy. They are an essential element of interaction design.
How do you define a good transition? Successful animated transition possesses the following five characteristics:
State changes in UI often involve hard cuts by default, which can make them difficult to follow. In the real world, most things don’t just appear or disappear immediately. When something has two or more states, then changes between states will be much easier for users to understand if the transitions are animated instead of being instantaneous. Let’s look at an example below where the user selects an item in a list to zoom into its detailed view. During expansion, the small card moves in an arc towards its destination as it expands into a larger card. This movement is inspired by the real world forces.
A well-staged animated transition guides your user’s attention and clarifies change states. This characteristic is directly related to the user focus and continuity. A good transition helps direct user’s focus to the right spot at the right time, it puts emphasis on the right elements depending on what the objective is. In the example below, the floating action button (FAB) transforms into header navigation elements comprised of three buttons. The first-time user cannot really predict an interaction that is about to happen, but properly animated transition helps the user stay oriented and not feel that content has suddenly changed. This transition helps guide the user to the next step of an interaction.