Skip to content
  • Home
  • Agro
    • Agro
    • Akuaponik
    • Hidroponik
    • Ayam Kampung
  • DIY
    • DIY
    • Rumah Kampung
  • Tech
    • Tech
    • Titanium Mobile
  • Media
    • Media
    • Downloads
    • Dashcam Drive
  • Misc
    • Pelbagai
    • Makanan
    • Fotografi
    • Idea
    • E-mau
  • Home
  • Agro
    • Agro
    • Akuaponik
    • Hidroponik
    • Ayam Kampung
  • DIY
    • DIY
    • Rumah Kampung
  • Tech
    • Tech
    • Titanium Mobile
  • Media
    • Media
    • Downloads
    • Dashcam Drive
  • Misc
    • Pelbagai
    • Makanan
    • Fotografi
    • Idea
    • E-mau
blog.azwan082.my


Blog ini tidak lagi dikemaskini, sila ke
👉 azwan082.my 👈
untuk dapatkan kandungan terbaru.

#CommonJS  #Javascript  #NodeJS  #Titanium Mobile

Lazyloading JS modules in Titanium app

On 1 November 2014 in Tech

In NodeJS project, usually modules are loaded at the beginning of the file:

var fs = require('fs');
var path = require('path');
var express = require('express');

When this NodeJS application being run, it loads all of the dependencies & start executing the program. In large application, there will be delay before the application can start operating, because of the dependencies loading.

For desktop or server application, this won’t be much issue, but in mobile app like Titanium, if it loads the whole dependencies during app launch, it might cause unresponsive app & consume large memory, even when those modules haven’t being used yet.

Another problem is there might be circular dependencies issue, in which module A require module B, but module B also require module A, and this lead to module A variable in B to become an empty object. Example:

// db.js - database module
var Person = require('model/Person');
Person.setup();

// Person.js - data model
var db = require('db');
db.execute('sql'); // TypeError, undefined is not a function

Restructuring the code flow is one method to fix, but in my experience, it cause a lot of repeated code

// Person.js
var Person = {};
Person.setup = function() {
     var db = require('db');
};

Person.getById = function() {
     var db = require('db');
};

Person.getAll = function() {
     var db = require('db');
};

Because of this, I use the lazyloading approach & make use of JS object getter to both solve the problem & make the code cleaner. The idea is to have a global variable, which will be included in each of the modules we have in a Titanium app, and this global object holds a reference to every modules we packaged into the app. This reference will then call a getter to do require() and return the actual module to the caller.

In addition, modules are categorized into folders which can act as namespace, to eliminate class name conflict

// globals.js
var g = {};

var modules = [
     'window/MainWindow',
     'ui/ContactList',
     'ui/ContactListItem',
     'model/Contact',
     'core/Db',
     'core/Http'
];

modules.forEach(function(mod) {
     var parts = mod.split('/');
     var namespace = parts[0];
     var className = parts[1];
     var obj = g[namespace];
     if (!obj) {
          obj = {};
     }
     Object.defineProperty(obj, className, {
          get: (function(path) {
               return function() {
                    return require(path);
               };
          })(mod),
          set: function() {}
     });
});

module.exports = g;

Now, the Person model class can be refactored like below:

// Person.js
var g = require('globals');
var Person = {};
Person.setup = function() {
     g.core.Db.execute('sql');
};
Person.getAll = function() {
     g.core.Db.execute('sql');
};

This is just a basic implementation of the idea, and you can extend it to support subnamespace & native module.

Share this post:
  • Share
  • Tweet
  • LinkedIn

Related posts:

  • Setup Titanium Studio environment for developing Titanium module (Android) on Windows
  • Android BOOT_COMPLETED handler module
  • Method calling thread for Titanium module (Android)
  • Titanium Studio unbound classpath container error
  • Webview evalJS return null in Android 4.2.2
  • Creating [object] in a different context than the calling function.
  • Enable x86 libs in production build Titanium app
  • Ti.Network.registerForPushNotifications no response
  • ScrollableView in ListView
  • Titanium iOS “build” is an unrecognized command

Filed under Tech with tags CommonJS, Javascript, NodeJS, Titanium Mobile

Post navigation

Previous Post Previous post:
Git download specific tag
Next Post Next post:
JS parseBool()

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Media sosial

  • facebook
  • instagram
  • twitter
  • pinterest
  • youtube

Carian

Artikel popular

  • Saiz standard kayu, papan dan plywood
  • Pemasangan dinding plywood rumah kampung secara solo
  • 3 Jenis Asas Sistem Hidroponik Yang Digunakan Dalam Akuaponik Serta Variasinya
  • Kepincangan dalam menggunakan paip PVC sebagai saluran NFT hidroponik
  • Cara membuat sistem NFT untuk akuaponik – Saliran masuk
  • Cara pasang pintu rumah
  • Jenis skru kayu
  • Pemasangan pagar reban ayam kampung

Artikel terkini

  • 2 video #emau dari 2020/0221 February 2020
  • Gaya hidup minimalis14 February 2020
  • How to sync Mac OS Photos Library to an external disk storage17 January 2020
  • Sejarah dividen KWSP10 January 2020
  • Sejarah dividen Tabung Haji10 January 2020
  • Sejarah dividen ASB10 January 2020
  • Selamat dekad baru 2020-an3 January 2020
  • Dashcam Drive #17 – Taman Danu Serian → Ranchan Recreational Park1 January 2020

Tag

1N2D Akuaponik Android Apache Ayam Kampung Bash C# Cache Cili CommonJS Controller Dashcam Drive E-mau Fedora Fotografi Git Gnome Happy Together Hidroponik Idea Invincible Youth iOS Java Javascript Ke Indonesia Ke Kita? Ke Jepun Ke Kita? Ke Korea Ke Kita? Kewangan ListView Makanan Mr. Bean PHP Python Rant Roundtable Plus RPM Rumah Kampung Star Golden Bell Subversion SVN Titanium Mobile Titanium Module Titanium Studio windows phone WrestleMania

Arkib

Perihal

@azwan082

Seorang pembangun perisian (software developer) untuk peranti mudah alih (mobile devices) dan laman web, menggunakan bahasa pengaturcaraan Swift (iOS), Java (Android), PHP, MySQL dan Javascript (aplikasi web). Blog ini adalah tempat untuk saya berkongsi perkara, minat dan projek sampingan, seperti berkebun, kerja² kayu DIY, video dashcam drive dan pelbagai lagi.

© 2021 blog.azwan082.my

Back to top
sponsored