Use key as main identity for st.camera_input widget

[lukasmasuch]

Describe your changes

If a custom key is passed to a st.camera_input widget it will be used as the main identity. This allows for dynamically changing other parameters in between reruns without causing the widgets to be recreated in the frontend.

GitHub Issue Link (if applicable)

• Related to [Coming soon] Persist widget identity when key is set, even if the parameters change #11277

Testing Plan

• Added unit and e2e tests.

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Contribution License Agreement

By submitting this pull request you agree that all contributions to this project are made under the Apache 2.0 license.

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Note

Use the widget key as the main identity for st.camera_input, and add unit/E2E tests (including a dynamic props scenario) to verify stable IDs and behavior.

• Camera Input Widget
  • Use key as main identity by setting key_as_main_identity=True in lib/streamlit/elements/widgets/camera_input.py.
• Unit Tests
  • Add test_stable_id_with_key ensuring the widget ID remains stable across rerenders with the same key.
• E2E Demo & Tests
  • App: add a dynamic st.camera_input controlled by a toggle to change label, help, and width while preserving state (e2e_playwright/st_camera_input.py).
  • Tests: introduce NUM_CAMERA_INPUT_WIDGETS=5 and update counts; add test_dynamic_camera_input_props validating label/help updates, width, and preserved value; import/utilize helpers click_toggle, expect_help_tooltip, expect_prefixed_markdown.

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[Copilot]

Pull Request Overview

This PR updates the st.camera_input widget to use the key parameter as the main identity when provided, allowing for dynamic parameter changes without recreating the widget in the frontend.

• Changed key_as_main_identity from False to True in the camera input implementation
• Added comprehensive unit tests to verify stable widget ID behavior when using keys
• Added end-to-end tests to validate dynamic property updates while maintaining widget state

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
lib/streamlit/elements/widgets/camera_input.py	Updated key_as_main_identity parameter to True for stable widget identity
lib/tests/streamlit/elements/camera_input_test.py	Added unit test to verify widget ID stability with custom keys
e2e_playwright/st_camera_input_test.py	Added e2e test for dynamic property updates and updated widget count constants
e2e_playwright/st_camera_input.py	Added test case with dynamic camera input properties controlled by toggle

[github-actions]

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