NativeScript Performance Monitor

Measure and show FPS and (on iOS) CPU usage!

20 sec video, showing off the plugin on iOS and Android

Installation

From the command prompt go to your app's root folder and execute:

tns plugin add nativescript-performance-monitor

Start monitoring

After adding the plugin you can start monitoring from code. There are a few options you can pass in as well (the options object itself is optional as well):

Option	iOS?	Android?	Description
`onSample?`	:white_check_mark:	:white_check_mark:	A callback function that gets invoked on every sample. If you don't want to use the default UI of this plugin you can use this to render your own UI. See the examples below for the function spec.
`hide?`	:white_check_mark:	:white_check_mark:	Set to `true` if you don't want the default UI to show. So roll your own or go ito stealth mode entirely.
`textColor?`	:white_check_mark:	:white_check_mark:	The text color of the monitor view (default white).
`backgroundColor?`	:white_check_mark:	:white_medium_square:	Background color of the monitor view (default black).
`borderColor?`	:white_check_mark:	:white_medium_square:	The border color of the monitor view (default black).

TypeScript

import { PerformanceMonitor, PerformanceMonitorSample } from 'nativescript-performance-monitor';
import { Color } from "color";

const performanceMonitor: PerformanceMonitor = new PerformanceMonitor();

// this would suffice..
performanceMonitor.start();

// .. but we want to show off the options ;)
performanceMonitor.start({
  textColor: new Color("white"),
  backgroundColor: new Color("black"),
  borderColor: new Color("black"),
  hide: false,
  onSample: (sample: PerformanceMonitorSample) => {
    console.log("FPS: " + sample.fps);
    if (sample.cpu) { // iOS only
      console.log("CPU %: " + sample.cpu);
    }
  }
});

JavaScript

var perfMon = require("nativescript-performance-monitor");
var color = require("color");

var performanceMonitor = new perfMon.PerformanceMonitor();

performanceMonitor.start({
  textColor: new color.Color("white"),
  backgroundColor: new color.Color("black"),
  borderColor: new color.Color("black"),
  hide: false,
  onSample: function (sample) {
    console.log("FPS: " + sample.fps);
    if (sample.cpu) { // iOS only
      console.log("CPU %: " + sample.cpu);
    }
  }
});

Stop monitoring

To stop receiving measurements and hide the monitor UI you can simply do this:

performanceMonitor.stop();

Usage with Angular

In any component, or even app.module.ts add:

import { PerformanceMonitor } from "nativescript-performance-monitor";

export class MyComponent {
  // use the constructor, or OnInit, or trigger from a button, or whatever really
  constructor() {
    new PerformanceMonitor().start({
      // options
    });
  }
}

Known issues (Android)

May crash when a Toast is shown on newer Android versions while you're using the default UI.
UI will hide when app is pauzed / resumed.