Dash

Added

- [2276](https://github.com/plotly/dash/pull/2276) Python typing definition generation for components `__init__`.
- [3035](https://github.com/plotly/dash/pull/3035) `PropType` generation for Typescript components allowing runtime prop validation when in debug mode.
- [3066](https://github.com/plotly/dash/pull/3066) Adds `window.dash_component_api` for components developer as alternative to removed `_dashprivate` props.
- Add `dash_component_api.useDashContext`, `dash_component_api.DashContext` to access the redux store and loading mechanisms.
- `DashContext.componentPath` hold the path to the current component.
- `DashContext.useLoading(options?)` selector to get a boolean if the component is loading.
- `DashContext.isLoading` in case you need to use outside of a functional component.
- `DashContext.useSelector` to create custom selectors for the connected redux store.
- `DashContext.useStore` get the Dash app redux store.
- `DashContext.useDispatch` to dispatch new actions on the Dash redux store.
- Add `dash_component_api.getLayout(path)` to replace `_dashprivate_layout`.
- [3029](https://github.com/plotly/dash/pull/3029) Add pip install based hooks to Dash functionalities.
- Packages can add an `entry_points` with key `dash-hooks` to their `setup.py` for a module to be run when a Dash app is started.
- Add `dash.hooks` methods to hook into Dash apps.
- `hooks.layout` takes the layout as argument and must return a layout, can be used to wrap or add to the layout of Dash apps.
- `hooks.callback` defines a callback to be added to Dash apps.
- `hooks.clientside_callback` defines a clientside callback to be added to Dash apps.
- `hooks.setup` is called before a Dash app is started to get an instance of the app as first argument.
- `hooks.error` to receive all callback errors.
- `hooks.index` to change the `Dash.index_string`.
- `hooks.route` to add a Flask route to the Dash app.

Removed

- [3066](https://github.com/plotly/dash/pull/3066) `loading_state` removed from components props.
- [3078](https://github.com/plotly/dash/pull/3078) Deprecations removals
- Removed `dash.development.component_loader`, components libraries now required to generate the components with `dash-generate-components`.
- `Dash.run_server` has been removed in favor of `Dash.run`.
- Removed `dcc.LogoutButton` component.
- Renamed all `long` references to `background`.

Changed

- [3093](https://github.com/plotly/dash/pull/3093) Changed default React version to 18.3.1
- `defaultProps` on functional components now emits a deprecation warning.
- Deprecation notice on strings refs.

Fixed

- [3080](https://github.com/plotly/dash/pull/3080) Fix docstring generation for components using single-line or nonstandard-indent leading comments
- [3103](https://github.com/plotly/dash/pull/3103) Fix Graph component becomes unresponsive if an invalid figure is passed
- [3190](https://github.com/plotly/dash/pull/3190) Fix issue with cache key generation by adding option to include triggered inputs. Fixes [#3189](https://github.com/plotly/dash/issues/3189)
- [3130](https://github.com/plotly/dash/pull/3130) Fix HOST variable when using conda.
- [3066](https://github.com/plotly/dash/pull/3066) Improve performance of context components re-rendering.

[2.19.1](https://github.com/plotly/plotly.js/releases/tag/v2.19.1) fix various bugs.

Added

- [2881](https://github.com/plotly/dash/pull/2881) Add outputs_list to window.dash_clientside.callback_context. Fixes [#2877](https://github.com/plotly/dash/issues/2877).
- [2903](https://github.com/plotly/dash/pull/2903) Add callback on_error handler, either globally on Dash init or per callback basis. Receives the exception as first argument, can return output(s) or None for `no_update`. Access to original callback context is preserved and `set_props` works inside the error handler.
- [2936](https://github.com/plotly/dash/pull/2936) Adds support for TypeScript 5.5+.
- [2789](https://github.com/plotly/dash/pull/2789) Add library loading capacity to `_allow_dynamic_callbacks`

Fixed

- [2898](https://github.com/plotly/dash/pull/2898) Fix error thrown when using non-existent components in callback running keyword. Fixes [#2897](https://github.com/plotly/dash/issues/2897).
- [2892](https://github.com/plotly/dash/pull/2860) Fix ensures dcc.Dropdown menu maxHeight option works with Datatable. Fixes [#2529](https://github.com/plotly/dash/issues/2529) [#2225](https://github.com/plotly/dash/issues/2225)
- [2896](https://github.com/plotly/dash/pull/2896) The tabIndex parameter of Div can accept number or string type. Fixes [#2891](https://github.com/plotly/dash/issues/2891)
- [2900](https://github.com/plotly/dash/pull/2900) Allow strings in layout list. Fixes [#2890](https://github.com/plotly/dash/issues/2890)
- [2908](https://github.com/plotly/dash/pull/2908) Fix when environment variables are ignored by Dash.run() at runtime. Fixes [#2902](https://github.com/plotly/dash/issues/2902)
- [2888](https://github.com/plotly/dash/pull/2888) Add id to dcc.Loading DOM. Fixes [#2878](https://github.com/plotly/dash/issues/2878)
- [2922](https://github.com/plotly/dash/pull/2922) Fix background callback hash_function when source is unavailable. Fixes [#1885](https://github.com/plotly/dash/issues/1885)
- [2915](https://github.com/plotly/dash/pull/2915) Fix 'AttributeError' when layout is a function that returns a list of components. Fixes [#2905](https://github.com/plotly/dash/issues/2905)
- [2956](https://github.com/plotly/dash/pull/2956) Add missing useEffect dependency to dcc.Loading component.
- [2909](https://github.com/plotly/dash/pull/2909) Rehighlights dcc.Markdown when it is updated, fixes [#2895](https://github.com/plotly/dash/issues/2895)

Fixed

- [2860](https://github.com/plotly/dash/pull/2860) Fix dcc.Loading to apply overlay_style only to the children and not the spinner. Fixes [#2858](https://github.com/plotly/dash/issues/2858)
- [2854](https://github.com/plotly/dash/pull/2854) Fix dcc.Dropdown resetting empty values to null and triggering callbacks. Fixes [#2850](https://github.com/plotly/dash/issues/2850)
- [2859](https://github.com/plotly/dash/pull/2859) Fix base patch operators. fixes [#2855](https://github.com/plotly/dash/issues/2855)
- [2856](https://github.com/plotly/dash/pull/2856) Fix multiple consecutive calls with same id to set_props only keeping the last props. Fixes [#2852](https://github.com/plotly/dash/issues/2852)
- [2867](https://github.com/plotly/dash/pull/2867) Fix clientside no output callback. Fixes [#2866](https://github.com/plotly/dash/issues/2866)
- [2876](https://github.com/plotly/dash/pull/2876) Fix pattern matching in callback running argument. Fixes [#2863](https://github.com/plotly/dash/issues/2863)