mirror of https://github.com/electron/electron
111 lines
3.6 KiB
Markdown
111 lines
3.6 KiB
Markdown
# powerMonitor
|
|
|
|
> Monitor power state changes.
|
|
|
|
Process: [Main](../glossary.md#main-process)
|
|
|
|
## Events
|
|
|
|
The `powerMonitor` module emits the following events:
|
|
|
|
### Event: 'suspend'
|
|
|
|
Emitted when the system is suspending.
|
|
|
|
### Event: 'resume'
|
|
|
|
Emitted when system is resuming.
|
|
|
|
### Event: 'on-ac' _macOS_ _Windows_
|
|
|
|
Emitted when the system changes to AC power.
|
|
|
|
### Event: 'on-battery' _macOS_ _Windows_
|
|
|
|
Emitted when system changes to battery power.
|
|
|
|
### Event: 'thermal-state-change' _macOS_
|
|
|
|
* `state` string - The system's new thermal state. Can be `unknown`, `nominal`, `fair`, `serious`, `critical`.
|
|
|
|
Emitted when the thermal state of the system changes. Notification of a change
|
|
in the thermal status of the system, such as entering a critical temperature
|
|
range. Depending on the severity, the system might take steps to reduce said
|
|
temperature, for example, throttling the CPU or switching on the fans if
|
|
available.
|
|
|
|
Apps may react to the new state by reducing expensive computing tasks (e.g.
|
|
video encoding), or notifying the user. The same state might be received
|
|
repeatedly.
|
|
|
|
See https://developer.apple.com/library/archive/documentation/Performance/Conceptual/power_efficiency_guidelines_osx/RespondToThermalStateChanges.html
|
|
|
|
### Event: 'speed-limit-change' _macOS_ _Windows_
|
|
|
|
* `limit` number - The operating system's advertised speed limit for CPUs, in percent.
|
|
|
|
Notification of a change in the operating system's advertised speed limit for
|
|
CPUs, in percent. Values below 100 indicate that the system is impairing
|
|
processing power due to thermal management.
|
|
|
|
### Event: 'shutdown' _Linux_ _macOS_
|
|
|
|
Emitted when the system is about to reboot or shut down. If the event handler
|
|
invokes `e.preventDefault()`, Electron will attempt to delay system shutdown in
|
|
order for the app to exit cleanly. If `e.preventDefault()` is called, the app
|
|
should exit as soon as possible by calling something like `app.quit()`.
|
|
|
|
### Event: 'lock-screen' _macOS_ _Windows_
|
|
|
|
Emitted when the system is about to lock the screen.
|
|
|
|
### Event: 'unlock-screen' _macOS_ _Windows_
|
|
|
|
Emitted as soon as the systems screen is unlocked.
|
|
|
|
### Event: 'user-did-become-active' _macOS_
|
|
|
|
Emitted when a login session is activated. See [documentation](https://developer.apple.com/documentation/appkit/nsworkspacesessiondidbecomeactivenotification?language=objc) for more information.
|
|
|
|
### Event: 'user-did-resign-active' _macOS_
|
|
|
|
Emitted when a login session is deactivated. See [documentation](https://developer.apple.com/documentation/appkit/nsworkspacesessiondidresignactivenotification?language=objc) for more information.
|
|
|
|
## Methods
|
|
|
|
The `powerMonitor` module has the following methods:
|
|
|
|
### `powerMonitor.getSystemIdleState(idleThreshold)`
|
|
|
|
* `idleThreshold` Integer
|
|
|
|
Returns `string` - The system's current idle state. Can be `active`, `idle`, `locked` or `unknown`.
|
|
|
|
Calculate the system idle state. `idleThreshold` is the amount of time (in seconds)
|
|
before considered idle. `locked` is available on supported systems only.
|
|
|
|
### `powerMonitor.getSystemIdleTime()`
|
|
|
|
Returns `Integer` - Idle time in seconds
|
|
|
|
Calculate system idle time in seconds.
|
|
|
|
### `powerMonitor.getCurrentThermalState()` _macOS_
|
|
|
|
Returns `string` - The system's current thermal state. Can be `unknown`, `nominal`, `fair`, `serious`, or `critical`.
|
|
|
|
### `powerMonitor.isOnBatteryPower()`
|
|
|
|
Returns `boolean` - Whether the system is on battery power.
|
|
|
|
To monitor for changes in this property, use the `on-battery` and `on-ac`
|
|
events.
|
|
|
|
## Properties
|
|
|
|
### `powerMonitor.onBatteryPower`
|
|
|
|
A `boolean` property. True if the system is on battery power.
|
|
|
|
See [`powerMonitor.isOnBatteryPower()`](#powermonitorisonbatterypower).
|