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Motion · 02 Initial and Animate
Series contents · Technology map
Stage: State and Transition · Editable example · Storage ID: motion-step-02
Goals and learning outcomes
- Learning outcome: Explain the role of Initial. Input case: First mount and state changes.
- Deliverable: A table of styles on first appearance and after transitions. Connect your rationale for handling First appearance to the code.
Prerequisites
Prepare the results of the Target state and API boundary exercises from Unit 1, “State-Based Animation”.
Key concepts and explanations
Initial
initial is the starting state when an element first appears. It is not always the same as the current selected state.
First appearance
Use initial=false to skip the initial motion. Distinguish remounting from a normal render.
Practice setup
First check the execution scope guidance on the example screen. The following describes the environment needed to extend the assignment in a separate project. The existing motion-01·02·03 examples are limited examples based on Motion JS animate. For React layout, AnimatePresence, and hooks exercises, install motion in a separate local React project and import from motion/react. Do not assume JSX runs directly in the editor; preserve CSP and isolation.
The linked example is a starting point. It does not implement every task below. Complete work beyond its supported scope in a separate project.
Practice tasks
- In src/day-2.tsx of a separate exercise project, create versions with motion.div initial and animate, and a version with initial=false. Use the existing Unit 1·14·28 examples only as starting points.
- Input condition: First mount and state changes. Baseline: Explicit starting values. Run under the baseline condition, then record observations and errors in notes/day-2.md.
- Variable to change: initial; new value: false. Run again with the same input path. Deliverable to save: A table of styles on first appearance and after transitions. Hypothesis to test: The initial entrance is skipped, while subsequent state transitions remain. Compare it with the actual results and record whether they agree and the causes of any differences.
Variables to observe
| Variable | Baseline | Change | Expected change / hypothesis |
|---|---|---|---|
| initial | Explicit starting values | false | The initial entrance is skipped, while subsequent state transitions remain. |
Predictions in this table are not measured results. Change one condition at a time and record why the actual result differs.
Completion criteria
- Required deliverable: A table of styles on first appearance and after transitions. You have results for both the baseline and changed conditions, allowing a comparison of 2 conditions, and have recorded the input values and execution environment.
- Your explanation of the differences between the two conditions connects both concepts: Initial and First appearance. For unexpected items, give at least 1 cause or reason they remain unresolved.
Self-check
- Which processing stage does Initial affect in this exercise? Input case: First mount and state changes.
- Variable to change: initial. Hypothesis to test: The initial entrance is skipped, while subsequent state transitions remain. Did the actual results agree with the hypothesis? Explain your evidence in terms of First appearance.
Official references
Linked example and execution scope
Example source · Runtime environments and limits
Interactive Initial and Animate experiment with cleanup of the resources used.
Source code and records are not overwritten automatically. Resetting an existing example also preserves your notes.
Next learning
Previous: State-Based Animation · Next: Configuring Transition