State Change Animations
Apply Disney's 12 principles when elements transform without leaving.
Principle Application
Squash & Stretch: Elements compress before expanding. A toggle switch squashes 5% before sliding.
Anticipation: Wind up before the change. Slight reverse movement (2-3px) before expanding.
Staging: Keep transformations centered on user focus. Don't let state changes distract from the interaction point.
Straight Ahead vs Pose-to-Pose: Define exact states. Button has rest, hover, active, disabled - each precisely designed.
Follow Through & Overlapping: Parts transform at different rates. Icon rotates before label fades in.
Slow In/Slow Out: Use ease-in-out for bidirectional changes: cubic-bezier(0.4, 0, 0.2, 1).
Arcs: Rotating elements follow natural arcs. Chevrons rotate on their center point, not linearly.
Secondary Action: Pair the primary change with supporting motion. Toggle sliding + color shift + icon swap.
Timing:
- Micro-states: 100-150ms (checkbox tick, radio fill)
- Standard states: 150-250ms (toggles, accordions)
- Complex states: 250-400ms (multi-part transformations)
Exaggeration: Overshoot slightly on state changes. Toggle goes 2px past, then settles.
Solid Drawing: Maintain element integrity during transformation. No distortion that breaks visual consistency.
Appeal: State changes should feel satisfying. Users clicked with intent - reward that intent.
Timing Recommendations
| State Change | Duration | Easing | Notes |
|---|---|---|---|
| Checkbox | 150ms | ease-out | Tick draws in |
| Toggle Switch | 200ms | ease-in-out | Overshoot slightly |
| Radio Button | 150ms | ease-out | Scale in from center |
| Accordion | 250ms | ease-in-out | Height + rotation |
| Tab Switch | 200ms | ease-in-out | Indicator slides |
| Button Active | 100ms | ease-out | Scale to 0.97 |
| Card Expand | 300ms | ease-in-out | All properties together |
Implementation Pattern
css.toggle { transition: all 200ms cubic-bezier(0.4, 0, 0.2, 1); } .toggle-knob { transition: transform 200ms cubic-bezier(0.34, 1.56, 0.64, 1); /* Overshoot */ } .toggle.active .toggle-knob { transform: translateX(20px); }
Accordion Pattern
css.accordion-content { display: grid; grid-template-rows: 0fr; transition: grid-template-rows 250ms ease-in-out; } .accordion.open .accordion-content { grid-template-rows: 1fr; }
Key Rule
State changes are reversible. The animation to state B should be the inverse of animation to state A. Test both directions.
