electron/docs/api/system-preferences.md
Shelley Vohr 280f9bf49c
feat: allow immediate MacOS notifications (#16060)
* feat: allow immediate MacOS notifications

* fix args->GetNext

* update docs/api/system-preferences.md

Co-Authored-By: codebytere <codebytere@github.com>

* address feedback from @ckerr's review
2018-12-14 13:46:46 -08:00

13 KiB

systemPreferences

Get system preferences.

Process: Main

const { systemPreferences } = require('electron')
console.log(systemPreferences.isDarkMode())

Events

The systemPreferences object emits the following events:

Event: 'accent-color-changed' Windows

Returns:

  • event Event
  • newColor String - The new RGBA color the user assigned to be their system accent color.

Event: 'color-changed' Windows

Returns:

  • event Event

Event: 'inverted-color-scheme-changed' Windows

Returns:

  • event Event
  • invertedColorScheme Boolean - true if an inverted color scheme (a high contrast color scheme with light text and dark backgrounds) is being used, false otherwise.

Event: 'high-contrast-color-scheme-changed' Windows

Returns:

  • event Event
  • highContrastColorScheme Boolean - true if a high contrast theme is being used, false otherwise.

Event: 'appearance-changed' macOS

Returns:

  • newAppearance String - Can be dark or light

NOTE: This event is only emitted after you have called startAppLevelAppearanceTrackingOS

Methods

systemPreferences.isDarkMode() macOS

Returns Boolean - Whether the system is in Dark Mode.

systemPreferences.isSwipeTrackingFromScrollEventsEnabled() macOS

Returns Boolean - Whether the Swipe between pages setting is on.

systemPreferences.postNotification(event, userInfo[, deliverImmediately]) macOS

  • event String
  • userInfo Object
  • deliverImmediately Boolean (optional) - true to post notifications immediately even when the subscribing app is inactive.

Posts event as native notifications of macOS. The userInfo is an Object that contains the user information dictionary sent along with the notification.

systemPreferences.postLocalNotification(event, userInfo) macOS

  • event String
  • userInfo Object

Posts event as native notifications of macOS. The userInfo is an Object that contains the user information dictionary sent along with the notification.

systemPreferences.postWorkspaceNotification(event, userInfo) macOS

  • event String
  • userInfo Object

Posts event as native notifications of macOS. The userInfo is an Object that contains the user information dictionary sent along with the notification.

systemPreferences.subscribeNotification(event, callback) macOS

  • event String
  • callback Function
    • event String
    • userInfo Object

Returns Number - The ID of this subscription

Subscribes to native notifications of macOS, callback will be called with callback(event, userInfo) when the corresponding event happens. The userInfo is an Object that contains the user information dictionary sent along with the notification.

The id of the subscriber is returned, which can be used to unsubscribe the event.

Under the hood this API subscribes to NSDistributedNotificationCenter, example values of event are:

  • AppleInterfaceThemeChangedNotification
  • AppleAquaColorVariantChanged
  • AppleColorPreferencesChangedNotification
  • AppleShowScrollBarsSettingChanged

systemPreferences.subscribeLocalNotification(event, callback) macOS

  • event String
  • callback Function
    • event String
    • userInfo Object

Returns Number - The ID of this subscription

Same as subscribeNotification, but uses NSNotificationCenter for local defaults. This is necessary for events such as NSUserDefaultsDidChangeNotification.

systemPreferences.subscribeWorkspaceNotification(event, callback) macOS

  • event String
  • callback Function
    • event String
    • userInfo Object

Same as subscribeNotification, but uses NSWorkspace.sharedWorkspace.notificationCenter. This is necessary for events such as NSWorkspaceDidActivateApplicationNotification.

systemPreferences.unsubscribeNotification(id) macOS

  • id Integer

Removes the subscriber with id.

systemPreferences.unsubscribeLocalNotification(id) macOS

  • id Integer

Same as unsubscribeNotification, but removes the subscriber from NSNotificationCenter.

systemPreferences.unsubscribeWorkspaceNotification(id) macOS

  • id Integer

Same as unsubscribeNotification, but removes the subscriber from NSWorkspace.sharedWorkspace.notificationCenter.

systemPreferences.registerDefaults(defaults) macOS

  • defaults Object - a dictionary of (key: value) user defaults

Add the specified defaults to your application's NSUserDefaults.

systemPreferences.getUserDefault(key, type) macOS

  • key String
  • type String - Can be string, boolean, integer, float, double, url, array or dictionary.

Returns any - The value of key in NSUserDefaults.

Some popular key and types are:

  • AppleInterfaceStyle: string
  • AppleAquaColorVariant: integer
  • AppleHighlightColor: string
  • AppleShowScrollBars: string
  • NSNavRecentPlaces: array
  • NSPreferredWebServices: dictionary
  • NSUserDictionaryReplacementItems: array

systemPreferences.setUserDefault(key, type, value) macOS

Set the value of key in NSUserDefaults.

Note that type should match actual type of value. An exception is thrown if they don't.

Some popular key and types are:

  • ApplePressAndHoldEnabled: boolean

systemPreferences.removeUserDefault(key) macOS

  • key String

Removes the key in NSUserDefaults. This can be used to restore the default or global value of a key previously set with setUserDefault.

systemPreferences.isAeroGlassEnabled() Windows

Returns Boolean - true if DWM composition (Aero Glass) is enabled, and false otherwise.

An example of using it to determine if you should create a transparent window or not (transparent windows won't work correctly when DWM composition is disabled):

const { BrowserWindow, systemPreferences } = require('electron')
let browserOptions = { width: 1000, height: 800 }

// Make the window transparent only if the platform supports it.
if (process.platform !== 'win32' || systemPreferences.isAeroGlassEnabled()) {
  browserOptions.transparent = true
  browserOptions.frame = false
}

// Create the window.
let win = new BrowserWindow(browserOptions)

// Navigate.
if (browserOptions.transparent) {
  win.loadURL(`file://${__dirname}/index.html`)
} else {
  // No transparency, so we load a fallback that uses basic styles.
  win.loadURL(`file://${__dirname}/fallback.html`)
}

systemPreferences.getAccentColor() Windows

Returns String - The users current system wide accent color preference in RGBA hexadecimal form.

const color = systemPreferences.getAccentColor() // `"aabbccdd"`
const red = color.substr(0, 2) // "aa"
const green = color.substr(2, 2) // "bb"
const blue = color.substr(4, 2) // "cc"
const alpha = color.substr(6, 2) // "dd"

systemPreferences.getColor(color) Windows

  • color String - One of the following values:
    • 3d-dark-shadow - Dark shadow for three-dimensional display elements.
    • 3d-face - Face color for three-dimensional display elements and for dialog box backgrounds.
    • 3d-highlight - Highlight color for three-dimensional display elements.
    • 3d-light - Light color for three-dimensional display elements.
    • 3d-shadow - Shadow color for three-dimensional display elements.
    • active-border - Active window border.
    • active-caption - Active window title bar. Specifies the left side color in the color gradient of an active window's title bar if the gradient effect is enabled.
    • active-caption-gradient - Right side color in the color gradient of an active window's title bar.
    • app-workspace - Background color of multiple document interface (MDI) applications.
    • button-text - Text on push buttons.
    • caption-text - Text in caption, size box, and scroll bar arrow box.
    • desktop - Desktop background color.
    • disabled-text - Grayed (disabled) text.
    • highlight - Item(s) selected in a control.
    • highlight-text - Text of item(s) selected in a control.
    • hotlight - Color for a hyperlink or hot-tracked item.
    • inactive-border - Inactive window border.
    • inactive-caption - Inactive window caption. Specifies the left side color in the color gradient of an inactive window's title bar if the gradient effect is enabled.
    • inactive-caption-gradient - Right side color in the color gradient of an inactive window's title bar.
    • inactive-caption-text - Color of text in an inactive caption.
    • info-background - Background color for tooltip controls.
    • info-text - Text color for tooltip controls.
    • menu - Menu background.
    • menu-highlight - The color used to highlight menu items when the menu appears as a flat menu.
    • menubar - The background color for the menu bar when menus appear as flat menus.
    • menu-text - Text in menus.
    • scrollbar - Scroll bar gray area.
    • window - Window background.
    • window-frame - Window frame.
    • window-text - Text in windows.

Returns String - The system color setting in RGB hexadecimal form (#ABCDEF). See the Windows docs for more details.

systemPreferences.isInvertedColorScheme() Windows

Returns Boolean - true if an inverted color scheme (a high contrast color scheme with light text and dark backgrounds) is active, false otherwise.

systemPreferences.isHighContrastColorScheme() Windows

Returns Boolean - true if a high contrast theme is active, false otherwise.

systemPreferences.getEffectiveAppearance() macOS

Returns String - Can be dark, light or unknown.

Gets the macOS appearance setting that is currently applied to your application, maps to NSApplication.effectiveAppearance

Please note that until Electron is built targeting the 10.14 SDK, your application's effectiveAppearance will default to 'light' and won't inherit the OS preference. In the interim in order for your application to inherit the OS preference you must set the NSRequiresAquaSystemAppearance key in your apps Info.plist to false. If you are using electron-packager or electron-forge just set the enableDarwinDarkMode packager option to true. See the Electron Packager API for more details.

systemPreferences.getAppLevelAppearance() macOS

Returns String | null - Can be dark, light or unknown.

Gets the macOS appearance setting that you have declared you want for your application, maps to NSApplication.appearance. You can use the setAppLevelAppearance API to set this value.

systemPreferences.setAppLevelAppearance(appearance) macOS

  • appearance String | null - Can be dark or light

Sets the appearance setting for your application, this should override the system default and override the value of getEffectiveAppearance.

systemPreferences.getMediaAccessStatus(mediaType) macOS

  • mediaType String - microphone or camera.

Returns String - Can be not-determined, granted, denied, restricted or unknown.

This user consent was not required until macOS 10.14 Mojave, so this method will always return granted if your system is running 10.13 High Sierra or lower.

systemPreferences.askForMediaAccess(mediaType) macOS

  • mediaType String - the type of media being requested; can be microphone, camera.

Returns Promise<Boolean> - A promise that resolves with true if consent was granted and false if it was denied. If an invalid mediaType is passed, the promise will be rejected. If an access request was denied and later is changed through the System Preferences pane, a restart of the app will be required for the new permissions to take effect. If access has already been requested and denied, it must be changed through the preference pane; an alert will not pop up and the promise will resolve with the existing access status.

Important: In order to properly leverage this API, you must set the NSMicrophoneUsageDescription and NSCameraUsageDescription strings in your app's Info.plist file. The values for these keys will be used to populate the permission dialogs so that the user will be properly informed as to the purpose of the permission request. See Electron Application Distribution for more information about how to set these in the context of Electron.

This user consent was not required until macOS 10.14 Mojave, so this method will always return true if your system is running 10.13 High Sierra or lower.