Keep awake

It is never a bare activate: a screen that holds the display on and never releases it is a phone that never sleeps, which the user experiences as a battery fault and never attributes to the app that caused it. hold() always returns the function that releases it.

Install

npx expo install expo-keep-awake

import { KeepAwake } from '@ng-native/expo/keep-awake';

The smallest useful example

import { Component, DestroyRef, inject } from '@angular/core';
import { KeepAwake } from '@ng-native/expo/keep-awake';

@Component({
  selector: 'app-recording',
  template: `<text>Recording...</text>`,
})
export class Recording {
  constructor() {
    inject(DestroyRef).onDestroy(inject(KeepAwake).hold('recording'));
  }
}

What it does

• hold(tag) - holds the screen on under that tag, and returns the function that releases it. The tag defaults to a package-wide constant. Holds are counted per tag, so two screens holding the same tag, or the default, each keep the screen on until their own hold is released; naming the tag is what tells them apart in holders.
• holders - a signal of the set of tags currently holding the screen on, for a debug screen that wants to say which.
• active - whether anything currently holds the screen on, computed from whether holders is non-empty.

Releasing the same hold twice does nothing the second time.

Without the module

On iOS and Android, a missing expo-keep-awake - never installed, or installed without the app being rebuilt since - throws a MissingModuleError when the service first reaches for it. Its message names the module and the commands that fix it; see Using a module.

On the web, and in a test that provides no fake, hold() still tracks the tag in holders and active, but nothing on the device changes and stop calls into a module that is not there safely.

Reference