fix: Allow dynamic value change for checkbox #1154

[marek-mihok]

The PR fulfills these requirements: (check all the apply)

• It's submitted to the main branch.
• When resolving a specific issue, it's referenced in the PR's title (e.g. feat: Add a button #xxx, where "xxx" is the issue number).
• When resolving a specific issue, the PR description includes Closes #xxx, where "xxx" is the issue number.
• If changes were made to ui folder, unit tests (make test) still pass.
• New/updated tests are included

---

This PR partially resolves issue #1154.

NOTE: Do not forget to update status in this comment once merged.

[mturoci]

Seems to not work for me, or maybe I am missing something?

from h2o_wave import main, app, Q, ui


@app('/demo')
async def serve(q: Q):
    if not q.client.initialized:
        q.page['form'] = ui.form_card(box='1 1 5 5', items=[
            ui.checkbox(name='checkbox', label='Checkbox', value=True),
            ui.button(name='toggle', label='Toggle'),
        ])
        q.client.initialized = True

    if q.args.toggle:
        q.page['form'].checkbox.value = True

    await q.page.save()

Screen.Recording.2023-07-31.at.10.05.42.AM.mov

[marek-mihok]

Good catch @mturoci! I've updated my solution and test cases. Now it should be working as expected.

[mturoci]

LGTM. Please go through the rest of your PRs and check them in the same manner. Thanks!