System API
isAppInstalled()
New in SDK 5.1
Checks if an app is installed given a UUID
import { isAppInstalled } from "system";
if (isAppInstalled("12345678-1234-5678-1234-567812345678")) {
console.log('App is installed!');
} else {
console.log('App is NOT installed!');
}
system.isAppInstalled(uuid: string)
Parameters
uuid: string
The UUID of the app to check presence of. The expected format is
12345678-1234-5678-1234-567812345678
launchApp()
New in SDK 3.0
Launches an app given a UUID
import { launchApp } from "system";
const args = { name: "Phil", number: 42, list: ["one", "two", "three"] }
launchApp("12345678-1234-5678-1234-567812345678", args);
system.launchApp(uuid: string, launchArguments?: any)
Parameters
uuid: string
The UUID of the app to launch. The expected format is
12345678-1234-5678-1234-567812345678
(optional) launchArguments: any
Arguments which are passed to the app being launched.
Variable: memory
Type: Memory
The Memory API provides information about the system's native memory usage, and the memory usage of the current application.
import { memory } from "system";
console.log("JS memory: " + memory.js.used + "/" + memory.js.total);
Interface: Memory
Memory interface.
Properties
readonly js
Memory usage details for JavaScript memory.
readonly monitor
Memory pressure monitor.
readonly native
Memory usage details for Native memory (graphics, operating system libraries, etc.)
Interface: MemoryPressureMonitor
Monitor for memory pressure events.
Properties
onmemorypressurechange
((this: MemoryPressureMonitor, event: Event) => any) or undefined
Event listener for changes in memory pressure conditions.
readonly pressure
"normal" or "high" or "critical"
Memory pressure condition.
"normal"
means that the application's memory usage is normal."high"
means that the memory usage is high, and the application should try to release some memory as soon as possible."critical"
means that the application is close to running out of memory and risks being killed if some memory is not released immediately.
Interface: MemoryUsage
Memory usage details
Properties
readonly peak
number
Maximum memory used since the application was launched, in bytes.
readonly total
number
Total memory available in bytes.
readonly used
number
Current memory in use, in bytes.