# nativeTheme

> Read and respond to changes in Chromium's native color theme.

Process: [Main](../glossary.md#main-process)

## Events

The `nativeTheme` module emits the following events:

### Event: 'updated'

Emitted when something in the underlying NativeTheme has changed. This normally
means that either the value of `shouldUseDarkColors`,
`shouldUseHighContrastColors` or `shouldUseInvertedColorScheme` has changed.
You will have to check them to determine which one has changed.

## Properties

The `nativeTheme` module has the following properties:

### `nativeTheme.shouldUseDarkColors` _Readonly_

A `boolean` for if the OS / Chromium currently has a dark mode enabled or is
being instructed to show a dark-style UI.  If you want to modify this value you
should use `themeSource` below.

### `nativeTheme.themeSource`

A `string` property that can be `system`, `light` or `dark`.  It is used to override and supersede
the value that Chromium has chosen to use internally.

Setting this property to `system` will remove the override and
everything will be reset to the OS default.  By default `themeSource` is `system`.

Settings this property to `dark` will have the following effects:

* `nativeTheme.shouldUseDarkColors` will be `true` when accessed
* Any UI Electron renders on Linux and Windows including context menus, devtools, etc. will use the dark UI.
* Any UI the OS renders on macOS including menus, window frames, etc. will use the dark UI.
* The [`prefers-color-scheme`](https://developer.mozilla.org/en-US/docs/Web/CSS/@media/prefers-color-scheme) CSS query will match `dark` mode.
* The `updated` event will be emitted

Settings this property to `light` will have the following effects:

* `nativeTheme.shouldUseDarkColors` will be `false` when accessed
* Any UI Electron renders on Linux and Windows including context menus, devtools, etc. will use the light UI.
* Any UI the OS renders on macOS including menus, window frames, etc. will use the light UI.
* The [`prefers-color-scheme`](https://developer.mozilla.org/en-US/docs/Web/CSS/@media/prefers-color-scheme) CSS query will match `light` mode.
* The `updated` event will be emitted

The usage of this property should align with a classic "dark mode" state machine in your application
where the user has three options.

* `Follow OS` --> `themeSource = 'system'`
* `Dark Mode` --> `themeSource = 'dark'`
* `Light Mode` --> `themeSource = 'light'`

Your application should then always use `shouldUseDarkColors` to determine what CSS to apply.

### `nativeTheme.shouldUseHighContrastColors` _macOS_ _Windows_ _Readonly_

A `boolean` for if the OS / Chromium currently has high-contrast mode enabled
or is being instructed to show a high-contrast UI.

### `nativeTheme.shouldUseInvertedColorScheme` _macOS_ _Windows_ _Readonly_

A `boolean` for if the OS / Chromium currently has an inverted color scheme
or is being instructed to use an inverted color scheme.

### `nativeTheme.inForcedColorsMode` _Windows_ _Readonly_

A `boolean` indicating whether Chromium is in forced colors mode, controlled by system accessibility settings.
Currently, Windows high contrast is the only system setting that triggers forced colors mode.

### `nativeTheme.prefersReducedTransparency` _Readonly_

A `boolean` that indicates the whether the user has chosen via system accessibility settings to reduce transparency at the OS level.